texts: Why is GTP, rather than ATP, used in nuclear transport?

texts: Why is GTP used for nuclear transport and not ATP, given that ATP hydrolysis is used to drive most cellular energonic reactions?


texts: Are there viruses that affect cells across different species?

texts:
I'm not a professional in biology nor a student, but I'm curious about this. To be more specific: why doesn't a plant virus affect animal cells?

I suspect that different kinds of cells have different ways to replicate DNA and that this is the reason for the specialization of viruses.

I wonder if someone in the field can explain this to me. Thanks.


texts: Does  spermatozoa and sperm have different meaning?If they are same why do wikipedia have 2webpages ? But most websites mention them as the same thing.I am confused .Thank you in advance


texts: From the question: Could a man be proved positive for a pregnancy test?. I don't mean if a man could be pregnant but if he runs a pregnancy test, it is possible for it to come out positive?


texts: How do we know which Eulerian path corresponds to the DNA sequence?

texts:
Bioinformatics textbooks explain one method to reconstruct the whole DNA
sequence from multiple reads. The method builds a graph and finds a Eulerian path in it. The Eulerian path corresponds to a DNA sequence.

However, the graph can contain more than one path. How do we know which path corresponds to the actual sequence?


texts: How does soap affect membrane permeability? Which component of the membrane does it affect?

texts: In a lab we used distilled water + 3 drops of soap to examine how beetroot would be affected by it. I believe the beetroots membrane denatured and a red pigment leaked from it. However, I cannot explain why this has happened. Can anyone explain the topic question to me?


texts: Are there "multi-frequency" signals within a human brain?

texts: I know that neurons can exhibit tonic and phasic firing, and also that a neuron is sometimes called an integrator. This makes me interested to know if there are activities in the brain that depend on two or more signals of different frequency occurring at the same time. For example, in a telephone system, two signals with a different frequencies at once(DTMF) are interpreted as 1. Is there anything similar in the human brain?


texts: What does this sentence about angina mean?

texts:
I do not understand this sentence

  Angina can be treated ambulatory (in out-patient) in stable angina.

I think ambulatory refers to ambulatory ECG monitoring.
So I understand this that you can treat stable angina based on ambulatory ECG.
How do you understand this sentence about "ambulatory" angina?


texts: Is the male bee's penis homologous to the female bee's stinger?

texts: Considering that when a bee stings it loses its stinger and dies, this is similar to the male drone losing its penis and dying after copulation. It also seems similar that each event basically rips the abdomen open. Are the two structures a homologous pair?


texts: I read the wikipedia page about sequence alignment and sequence assembly but I have not been able to find any difference between the two. What is the difference between sequence alignment and sequence assembly? If there is no different why are the terminologies different?


texts:
I live in my hostel in NIT Tiruchchirapalli, in India. My hostel is infested with these beetle-like insects.

These insects posses a hard shell, if you flick them off the wall, they make a "tap" sound when they hit the ground. They're capable of flying but mostly stay on walls, sometimes even motionless. They also seem to be rather stupid, even for an insect. They don't attempt to escape even in life-or-death situations
tl;dr
What are these insects?


texts: I've found this bug in my appartment today and I was wondering what insect it is? Thank you.


texts: My question is whether mutations which lead to evolution occur by any environmental force or it occur spontaneously? I have read in genetics that x-rays, ultraviolet rays and chemical mutagens are the causes of mutation but how are they responsible for evolutionary mutations?


texts: What is the viability of Intelligent Design as a supplement to chemical abiogenesis and Darwinian Evolution?

texts:
First of all I am not endorsing Intelligent Design (Wikipedia link); I'm asking this because I (someone who does not have a background in biology, organic chemistry, or philosophy) got into a conversation with someone who does endorse it, and I'm trying to see his point of view as far as rationality can allow. Second of all, I apologize for any vagueness; Intelligent Design isn't well enough defined as a theory for me to help that. I also apologize if this is rehashing content already plentiful on the Internet, but for my purposes I can't simply depend on the likes of Wikipedia or Talk Origins, so what I'm looking for here instead is to take the opposite approach and see, based on your informed minds, if there could possibly be any reasonable likelihood of an ideal ID theory being adopted.

  I'm looking for the most favorable consideration for what ID might be
  if it were best developed as a viable hypothesis or theory to get an
  idea of how far such a discussion is worth taking. An unbiased,
  informed Devil's advocate, if you will.

My cursory investigation of what Stephen Meyers (video link) and Michael Behe (video link) say (correct me if I'm wrong) seems to be that either the first cell was likely designed intelligently judging by the complex code of DNA and that evolution took course from there, or that the first cells were made and many instances of evolution were from some kind of intelligently guided mutations as was needed to make "irreducibly complex" cells or body functions (whether the guidance stops after the Cambrian or continued even to the point of making different types of new bacteria and different types of apes/humans or whether every single mutation and adaptive ability is being guided, I'm not sure if they're at any consensus, and that's why I don't know if I should stop my question at abiogenesis or include evolution). The person I spoke with also brought up some specific claims (everything looks designed, DNA has ordered, complex information, blood clotting is irreducibly complex, ID can and has make predictions like decades ago that "Junk DNA" wasn't junk) that I don't need you to debunk (I have Google).

But if there could be any possible support or truth to any of the above, I would appreciate knowing about that. (Again, Devil's advocate so I can be informed and understand where the points come from.) Reading an ID book alone, it would be in places hard to know where they differ from actual scientific conclusions. After all, when someone who seems to know what they're talking about and can explain something in technical detail says that something is impossible or extremely unlikely, it's hard for me to know why they would be wrong (are they ignoring other possibilities? misrepresenting facts? are they really right and just getting the cold shoulder from an atheistic scientific community because it implies a deity?). So I focus on mainstream sources, even if they don't bother entertaining ID and leave me ignorant of its possible virtues. And thus I'm hoping someone from this informed community might enlighten me to what those possible virtues might be.


texts: Why don't carrier proteins require energy to change shape?

texts: I know that carrier proteins can be used for both passive and active transport, but I am referring to the facilitated diffusion aspect. Even though facilitated diffusion via carrier protein goes along the concentration gradient, the protein still must change its shape, from what I understand. Why does this process still not require ATP, and why does it require ATP to go against the concentration gradient in the same manner?


texts: Difference between Medical and Airport scanner radiation

texts: What is the difference between radiation doses of a medical scanner and airport security scanner (X-Ray full body scan)? Is it the same kind of radiation? Does it pose any danger for people who fly often?


texts: How do we know that the "original animal exposure event" of a human to the Covid-19 virus occurred between October and December 2019?

texts:
In a Yale med page (interview) on Covid-19 from January it is said that

  The molecular dating of the virus genomes indicates that the original animal exposure event happened sometime between late October and early December of last year, very near the times that the first cases were detected. This is unlike Zika virus, for example, where transmission occurred for many months before the virus was detected.

To someone unschooled in molecular dating, how do you explain that we (seem to) know with such precision when the "original animal exposure event" occurred in that October-December timeframe?


texts: Photosystem 1 and 2; P680/P700; Chlorophyll a/b

texts:
I am getting slightly confused about how the above relate to each other. My current understanding is that P680 and P700 refer to the primary pigment reaction centres in Photosystems 2 and 1 respectively, with the numbers giving the peak wavelength of absorption. Now I initially thought that one of these primary pigment reaction centres must be composed of chlorophyll a and the other of chlorophyll b, hence the slightly differning absorption wavelengths. Instead, here it seems to suggest that the primary pigment reaction centre is always chlorophyll a. Most sources I have looked at do not specify what forms the primary pigment reaction centre (the Wikipedia article on photosynthetic reaction centre, for example, does not state for the general case of for photosystem 2; however it does mention that photosystem 1 has a special pair of chlorophyll a molecules at the centre).

So my specific questions are:

Is the primary pigment reaction centre in both photosystem 1 and 2 (i.e. P700 and P680) a pair of chlorophyll a molecules?
If so, what is chlorophyll b? Is it simply an accessory pigment?
Finally, if it is the case that the primary pigment reaction centre is chlorophyll a in both cases, how can it be that it absorbs at a different wavelength in the two photosystems if it is the same molecule?


texts: What exactly happens if during translation, an amino acid is not present?

texts:
Lets say that the cell wants to make a particular protein. Transcription of the appropriate gene is done and the mRNA is made. mRNA attaches to the ribosome and the translation is initiated in a "normal" way.

What exactly would happen if an amino acid required in the protein is absent ? I know that the protein would not be manufactured properly but I want to exactly know what would happen to the ribosome and the mRNA. Are they destroyed? Are they simply separated? Who regulates this?


texts: Is breathing a reflex action or is it an intrinsic process?

texts:
The process of breathing is controlled by respiratory centers in the brain stem. Do these centers have an innate activity, i.e., just send out signals to breathing muscles intrinsically, and have the rate and manner in which they do so modified by various regulatory factors?

Or are they driven by imbalances (in levels of oxygen, carbon dioxide, hydrogen ions) like a reflex? Let's say that hypothetically these levels remain static in an acceptable state such that this reflex is no longer needed, would breathing stop since there's no longer a driving motive or would it continue because the respiratory centers have an intrinsic activity?


texts: Are (muscle) satellite cells the same as muscle stem cells?

texts: In terms of muscle: are the terms 'satellite cell' and 'muscle stem cell' interchangeable? That is, are there muscle stem cells that are not satellite cells, or vice versa?


texts: To understand why satellite cells are genetically inactive in Barr body

texts:
DAPI is used as a stain for DNA heterochromatic and euchromatic regions. The Barr body is heterochromatic.
In the slide of a normal human female cheek's somatic cells, there is apparently no other clear dark spot inside the nucleus than the Barr body against the nuclear inner membrane. - - I used an old microscope so my observation may be wrong as pointed in the comment.

How can you deduce from the given slide that the spot really contains inactive satellite cells that are not used genetically?
Why is the active X chromosome not visible by the same staining method? (It probably can be made visible by some other staining method.)


texts: What is the name of this black-ochre striped snake?

texts:
I've seen the following snake (?) near Calvi (on Corsica):

I guess it was about 50cm long.

What is the name of this type of snake?


texts: How do mosquitoes orientate in the darkness?

texts:
An annoying mosquito (Culicidae) which kept me awake nearly the whole night lead me to this question.

I have heard that mosquitoes can smell CO2 which could help them to orientate in the darkness, but how do they avoid obstacles and know where to land? I was browsing the wikipedia article but did not see an explanation for this, can somebody explain this to me?

I also wonder about the purpose of their loud, annoying sound (afaik only females produce it), which i would think as an evolutinary disadvantage, but this would be another question...


texts: Why is the null hypothesis of trait evolution Brownian motion?

texts:
Many models of continuous trait evolution assume that traits evolve according to Brownian motion. What is the biological or physical basis for this choice?
I realize there are models that do not assume Brownian motion, but what I am interested in asking is why the null model is so often chosen to be Brownian motion.


texts: How are presynaptic burst firing signals transmitted post-synaptically?

texts:
Neurons can exhibit burst firing and this presynaptic process basically results in a flurry of action potentials being fired in a short time window.

I'm, however, wondering how these signals are further relayed once they synapse onto other neurons? Specifically, does each action potential in the burst volley generate another post-synaptic action potential, or is the bursting somehow averaged to then transmit either one or no action potential post-synaptically depending on long the burst train was?


texts:
What was the first piece of work in computational biology? I'm ideally looking for a paper.

I am not interested in works that involve data management or data analysis but work that model biological processes through numerical simulations or numerical approximations of analytical results.


texts: Which cells are prefered by the HIV virus to establish an infection?

texts:
We always read that HIV infects CD4 cells, macrophages, and dendritic cells. However, is it a common event for HIV to infect non-immune cells within a host? If not, why?

And also if not, why are immune cells the main target of HIV? I could not find information on Google or Google Scholar on this topic. I imagine it doesn't have to do solely with the presence of the expression of co-receptors such as CD4, CCR5, CXCR-4, DC-SIGN etc that attract the virus only to immune cells.

I would like a more complete explanation than this obvious one. For instance, what advantages are provided for the virus to prefer infecting immune cells over non-immune cells?


texts: Why is the resting membrane potential of excitable tissue not affected by the extracellular sodium concentration?

texts:
I know that the resting membrane potential for excitable tissue (eg, nerve) is primarily determined by the electronegative difference between the inside and the outside of the membrane for potassium ions, as they are most permeate ion by far. And since the membrane is largely impermeable to sodium, it's diffusion potential is insignificant, as such it does not contribute much to the resting membrane potential.
However, is it not correct to think that if the concentration of sodium ions in the extracellular fluid drops, outward diffusion of the positive potassium ions will increase, because the outside of the membrane is now less positive (more negative), subsequently making the diffusion potential of potassium and the resting membrane potential more on the negative side and further from the action potential threshold. I am asking this because my professor was mentioning factors that affect the resting membrane potential, and he mentioned that the ECF concentration of sodium has no effect on the resting membrane potential.


texts: brain activity responsible for imagination

texts:
Which part of brain is responsible for advance or unseen imagination
For example:ones brain can make a situation in mind which is impossible to happen ...which part of brain is hyper active?


texts: Time scale for cAMP-dependent pathway cascades

texts:
What is the time scale for cAMP-dependent pathway cascades that start at the level of ligand binding to a G-protein receptor and finish at the level of gene transcription regulation?
For example, when corticotropin releasing hormone binds to CRH receptor 1, a cAMP-dependent pathway cascade is initiated, which ultimately leads to an upregulation in the transcription of proopiomelanocortin (POMC) mRNA.
I recognize that this is a very broad question, that is likely highly case dependent (i.e. different from receptor-ligand pair to receptor-ligand pair). Nonetheless, are we looking at several hundred milliseconds? Several seconds? Several minutes?
In the case of CRH, how quickly does CRH-CRH receptor 1 binding lead to the upregulated transcription of POMC mRNA?
If there are any good sources to read about this, I would greatly appreciate it!


texts: What does it mean for sodium and water reabsorption to be "coupled" in the nephron?

texts:
If sodium is transported across the tubule membrane down the concentration gradient established via the $Na^+$/$K^+$ exchanger via symport with glucose and antiport with hydrogen, and water is transported via aquaporins...how is this coupled? They don't have the same transporter. This seems like they are independent.

Is this related to concentration gradients (more $Na^+$ in epithelial cells --> water wants to follow osmotically)? If so, why is $Na^+$ controlling whether water is reabsorbed or secreted, and not some other ion?


texts: Accurate surveys of urban pigeon and bird populations

texts:
I've been working on an assignment to develop mathematical models of urban pigeon populations. (As a disclaimer, this is part of a math course, not a biology course). I already understand the mathematics behind this and have developed several plausible models, but I'm at the stage where I need more detailed data in order to validate my models.

It's surprisingly difficult to find accurate population dynamics data for urban pigeons (especially given my inexperience with this kind of a literature search and general "unsophisticated" understanding of biology).

I do have access to some journals (e.g., via my university library, Google Scholar and Amazon.com), but the best resource I've been able to come up with so far is Illinois Birds: A Century of Change (published by the University of Illinois). The books on urban bird populations I've found so far all seem to be targeted to bird watchers (which I'm not).

Is anyone aware of a detailed/accurate data set on population dynamics (either of urban pigeon populations in particular or of urban bird populations in general)?


texts:
As far as the genetic content of each cell is concerned I have read to my satisfaction that all cells of a person's body except the red blood cells (with no nucleus and so no genetic message) and the gametes ( with just half the genetic copy or 23 of the 46 chromosomes) have the same DNA copy and so all the 60,000-80,000 estimated genes. The only difference is that which genes are active and which are dormant. For example the gene for insulin would be present in all cells but would be active and functional only in the cells of pancreas assigned the function of insulin production.

My question is:-

  What is the factor or process or molecule or information that
  tells a cell or helps it to activate the genes necessary for its own
  growth and more importantly its designated function?


texts: I was out walking one night (In Florida) when I spotted this creature sliding around in the grass. I believe it may be a New Guinea Flatworm, but not quite sure. Could anyone please provide a definite ID? Thank you!


texts: How does a higher channel density increase speed of propagation of an Action Potential?

texts:
If there is a higher density of sodium channels then there will more Na$^+$ flux in the cell. So it's like trying to pass more material through a pipe and therefore the speed of action potential (AP) propagation will be more. This is what comes to me intuitively, but I am not sure about my answer.

Can anyone explain in better words, how the speed of an AP increases with increasing channel density?


texts:
I've spent some hours trying to understand what exactly is a phosphoester bond, but I'm still confused and at this point I just want to throw myself out of the window. I've already read that post which treats the question but it doesn't really help me since, according to the link given by WYSIWYG♦:

  A phosphoester bond is a bond between the phosphorous atom of a phosphate group and an oxygen atom.

But considering the answer of electronpusher:

  Each nucleotide contains one phosphoester bond (between a phosphate O and sugar 5'-C).

It doesn't really make sense to me, since such a bond (in a nucleotide) is not exactly a bond between the phosphorous atom of the phosphate group and an oxygen atom (that is, it's a O-C bond, not a P-O bond).

So, what is exactly a phosphoester bond? Is it a O-glycosidic bond between the sugar (ribose or 2'-deoxyribose, in a nucleotide) and the phosphate group? Or is it the bond that there is between the phosphorous atom of a phosphate group and an oxygen atom of the same phosphate group?

I'm really confused and desperate by all this, so any help would be greatly appreciated. Thanks in advance!


texts:
Im doing a project with structural variation created by recombination within the human genome during spermatogenesis, where im especially examining intrachromatid homolog recombination.

I find that chromosome 19 is less prone to recombine and form strutural variation. I know that chromosome 19 has a high gene density and have a high amount of linked genes, so a low CentiMorgan unit. But some articles, states that chromosome 19 contains duplicated regions, which i would assume would be prone to recombine with intrachromatid recombination.

So my question is, from an evolutionary perspective, does anyone know any articles, which might describe why chr 19 is less likely to recombine. if chromosome 19 have a higher amount of life essential genes, or is it simply the high density between the repeats which affects the recombination (so sort of like heterchromatin structures).

I've looked and cannot find any results to support that chromosome 19 are "more different" when compared to other autosomes. As an example chromosome 1 has a higher CentiMorgan unit and are thus more likely to recombine, so "it" handles structural variations better, but it still contains important genes.

Thanks for your help.


texts: Will climate change affect flower population?

texts: There is a flower population elevated 1000 meters above sea level.  If climate change causes a 12⁰C increase in temperature over the next 10 years, what will happen to the flowers?


texts: If an ethnic group holds nearly 100% of a particular haplogroup, does it means that people who have this haplogroup are their descendants?

texts:
Let me give you a hypothetical example. If the Egyptians were 100% E3b1, and the Levantines 50%, and the Anatolians 25%. Does this indicate that the Levantines and Anatolians are descended from Egyptians?

But what if instead of Egyptians, it was a distant people like Vietnamites who were 100% E3b1?


texts: I want to know that what the name of the organ used by lice for ingestion is? (also please explain if possible). In my research, I got this wiki page that didn't help me out. Then I found this link which says that it sucks blood and pumps up that with a tube so, I want the specific name of that organ.


texts: how many spores are needed to "infect" a wall?

texts:
There's cardboard box in my room that used to be in another room that had mold all over the walls and it still smells moldy. This probably means the air in my room is polluted with mold spores.(right?)

If only a few spores stick to my wall could this "infect" the wall?

How many spores are actually needed to start infecting the walls in my room?

I threw that cardboard away, but I still wonder about the remaining spores


texts: The link between muscle mass and muscle strength and how to train for each

texts:
I'm getting into my fitness and am beginning to see an increase in muscle mass. However, I look at people like Bruce Lee, Elliott Hulse, Mohammad Ali and Wim Hof who are capable of incredible strength but do not look as "buff" as people like Arnold Swarzenegger. It is clear that an increase in muscle mass does not necessarily lead to an increase in strength.

How is training for strength different to training for mass?

To add a new angle to this question, is there a correlation between the two?


texts: Whenever I look up this topic, all I get is articles that say "Bed bugs don't carry disease...", but they never explain why?  Is it something in their saliva that kills microbes?  Something in their gut maybe?  When they are crawling over the floor wouldn't it be logical that they would carry microbes, I mean cockroaches do?


texts: Please help identify this little bug and how I make them go away.


texts: Public database of animal specifications

texts:
I'm a math teacher looking for data to help my students interested in biology complete a quantitatively flavored study of animals. (As a math person, I apologize if I'm not using discipline-appropriate vocabulary in my request here.)

I'd like to find a publicly available database that lists different animal species along with their average measurements of various biological variables (body mass, heart rate, body temperature, length, lung capacity, etc.). Can anyone point me to something?

I'm interested in having my students study the relationship between pairs of variables (i.e. body mass and heart rate), to model this relationship via an appropriate function, and to use their function to make predictions. To hone their models, students will need access to known data about these variables for a number of different animals. I could have them look up all of this data in separate places on the internet, but I'm hoping to find one location that has all (or most) of it.

Thanks in advance.


texts: Geographical distribution of malaria and tuberculosis

texts: Unlike malaria, tuberculosis (TB) is found across the whole world. Why and explain? I mean why are people affected with TB more than malaria and some say that in cold and developed countries malaria is less but TB cases are more.


texts:
Has anybody had any success in extracting cell free DNA from plasma without using expensive kits? I've already spent a lot of my own blood trying to use standard phenol/chloroform methods with very minimal yield. I know it's possible that since I am not pregnant and don't have cancer (I hope) my blood may not have a large quantity of cell free DNA to begin with but I'm afraid to start using precious experimental samples until I'm confident I have a technique that will work.

For some background, cell free DNA is DNA that is circulating in the plasma (as opposed to the majority of DNA which is cellular). This has become an exciting new way to analyze fetal DNA from a mother's blood without doing a dangerous amniocentesis. There's also strong evidence that tumour DNA can also be found in some abundance this way (most studies seem to be with prostate cancer).

Qiagen has a kit for sale to extract this DNA but it is pretty expensive and I would still think that phenol/chloroform would give me a high (if less pure) yield. There is a paper in Cancer Biomarkers 2013 by Mazurek et al that claims that compares methods and shows a reasonable yield with this method but I haven't reproduced it. Has anybody here had success and if so what modifications did you use? Is it just time to move on to using samples that are more likely to have larger amounts of cell free DNA?


texts: Does Pasteur's experiment contradict an origin of life?

texts:
To my understanding, Pasteur’s experiment demonstrates that life is only made from life. If this is true, then how could origin of life (aka. abiogenesis) ever have happened?

It seems to me that Pasteur’s experiment and the theory according to which there is abiogenesis contradict each other. Do they?


texts: Does applying sugar to the tongue taste buds releave sugar withdrawal symptoms?

texts:
I found several online articles discussing sugar withdrawal symptoms that people experience after cutting back on large sugar intake.

http://healthyeating.sfgate.com/refined-sugar-withdrawal-symptoms-9911.html

http://www.growyouthful.com/remedy/sugar-addiction-recovery.php

One question that came to mind, was the following: If one experiences a sugar withdrawal, what happens if they apply sugar to the tongue, but do not digest it? Does that trick the brain into stopping the sugar withdrawal, or is it far more complicated than that?


texts: Why did humans/animals evolve to become self-aware of their own thoughts.  That is, why don't humans act and compute like a machine, or walking zombie.  In my mind, such creatures would still be as smart and equally capable of surviving, the only difference being they don't experience the phenomenon of self-awareness. (To understand my question think: unconsciously sleep walking)


texts: Devonian Fish Diversity--What Would it Have Looked Like?

texts:
For 70 million years, the oceans, lakes and rivers of the world teemed with seven groups of fish:

Placodermi

Acanthodii

Agnatha

Chondrichthyes

Sarcopterygii

Actinopterygii

Now two of those groups have been extinct for hundreds of millions of years, but they were still a pretty big deal back then.

So by using modern fish as analogies, which niche(s) did which group of fish occupy during the Devonian Period?


texts: difference between blastula and blastocyst

texts: What is the difference between these 2 terms. I believe that blastocyst is for animals, but structurally is there any difference? And how would you be able to identify each?


texts: Does the word "polymorphism" refer to the gene, the phenotype, or both?

texts:
In genetics, does the word "polymorphism" properly refer to genes, to phenotypes, or both? For example, if there are two alleles that lead to differences in the structure of the D2 neuroreceptor, would I talk about "a polymorphism in the gene for the D2 neuroreceptor" or "a polymorphism in the D2 neuroreceptor"? I've seen both uses in the literature, but it's not my primary field, so I don't have a feel for whether one is more widely accepted.

Bonus question: is there a preference regarding "polymorphism of," "polymorphism in," and "polymorphism on"?


texts: Alkaline Phosphatase and Ligase Protocol for Cloning

texts:
In the image the circular molecule is a restricted vector and the linear red molecule is a DNA insert.
I found this protocol in my lessons notes, but I don't understand how it is possible that ligase catalyzes a reaction between 5'-OH and 5'-P. This reaction should form as product a 5'-5' bridge between the 2 nucleotides of the insert and the vector.
Usually Ligase repairs nicks between 5'-P and 3'-OH thus creating 5'-3' bonds between nucleotides that are normal in nucleic acids, so my question is how is it possible for the DNA to be functional even though it has a 5'-5' bond?


texts:
Pardon my ignorance ... A lip is apparently a very sensitive tactile device - as it at-least serves to warn it's owner they may just be about to consume something that could cause injury. Primates (including humans), dogs, cats, sheep, buffalo, elephants, some fish, octopodes - to name a few, have a lip.

How have lips evolved to be nearly ubiquitous across animals? Why have they evolved into a beak/bill in some birds & fish? What niche/purpose do they fulfill?


texts: Eating possibly spoiled food in the fasted state - is it considered protective against the potential harm?

texts:
It is a known fact that the acidic environment in the stomach serves several purposes, such as providing suitable conditions for primary chemical digestion of food molecules and protection from certain kinds of infections which may be caused by bacteria taken in with the food - I'm not giving any specific reference, any basic gastrointestinal system physiology text will give this information and more.

My question relates to the latter role I mentioned above: about the stomach being most acidic when in the fasted state (i.e. the period between about 2 hours after eating and eating again).

This article describes a stomach pH of 1.7 in the fasted state and a pH level of 6.7 shortly after eating

My question:  If I'm about to eat food that is potentially contaminated by bacteria, would it be better if I wait until I'm well into the fasted state (i.e., very hungry) in order to minimize the risk of indigestion or any other adverse outcome of eating spoiled food? If so, would the reason be because my stomach is as acidic as possible in that state?


texts: Blood become denser when you are dying of deshidration? I mean, when you are dying of deshidration does your body extract water from blood to survie more time?


texts: Why is the mechanism of inheritance for this disease autosomal dominant?

texts:
An unrelated couple has a daughter and a son with the same rare condition. Neither parent has any obvious signs of the condition, but the father's mother (paternal grandmother) and her brother have the same condition. Select the most likely mode of inheritance:

  A. X-Linked
  B. Autosomal recessive
  C. Autosomal dominant
  D. Multifactorial
  E. Mitochondria

The correct answer is C. But I'm confused why it would be autosomal dominant when neither parent has the phenotype. I thought it might be autosomal recessive, even though this mode usually does not have a family history, just because of the fact that the paternal grandmother and her brother both had the disease, and this is consistent with the horizontal pattern associated with autosomal recessive inheritance. For it to be autosomal dominant, the disease would have to be incompletely penetrant, which seems like a less likely scenario than it being autosomal recessive.

Can someone explain why it is dominant, not recessive?

Thanks!


texts: How it will taste if one puts two substances on tongue simultaneously?

texts: If we put two substances having different taste on tongue simultaneously how it will taste? Does specific part of tongue is sensitive to specific taste?


texts: Which strand of a gene specifies a protein?

texts:
A gene is a segment of DNA (I hope double stranded) and each strand when transcribed form a mRNA and after being translated a protein. As from each gene there are two proteins that are being formed. Now how do these two proteins determine the expression of the gene?

I may be wrong. Please explain if so.


texts: Human Bones classification and anatomy quiz

texts:
I'm a junior Biology Student and I came across this Human Anatomy Question:

In respect to the bone characteristics, mark the correct answer:

A) Even bones: Palatine, Inferior jaw, Parietal.

B) Examples of Long Bones: Sternum and Radius-clavicle.

C) Some Mixed Bones are (I couldn't find a better translation for "ossos mistos" in portuguese): vertebrae, ribs, hip bones.

D)Plane Bones protect organs and form cavities, for instance we have: Ribs and Sternum.

E)Odd and Plane Bones: Occipital, Frontal and Sternum.

I am almost sure that options A through C are incorrect. I'm between options D and E, but in option E I am really sure only that the Sternum Bone is correct. I couldn't find a reliable source that said explicitly that the Occipital and Frontal Bone are Plane and Odd.
And I think option D has a flaw mainly because the Sternum Bone does not form any cavities.


texts: Can Phosphogycolate buildup in a plant kill it?

texts: I'm trying to think of some things for the science fair, for part of my experiment I need to know if Phosphogycolate build up in a plant can kill it. Also, are there any chemicals that may disrupt the enzymes which break down phosphogycolate. Thanks!


texts: Are the transitions between the different brain frequencies states easy to see on an EEG?

texts: Are the transitions between the different brain frequencies states: Gamma to Beta, Beta to Alpha, Theta to Delta, etc. easy to distinguish on an EEG? How quickly can the brain transition between any of these states?


texts: Are both B and Y ions required to determine the sequence of a protein by mass spectrometry?

texts:
I was wondering if both all b and y ions are required to determine to order of the amio acids in a peptide.

In my opinion knowing only ALL B ions or ALL y-ions is enough to determine the sequence of the amino acids in a peptide. I was also wondering how these b and y ions are differentiated in a spectrum?


texts: Can it always be determined if an animal is a carnivore, omnivore, or herbivore by its teeth or are there exceptions?

texts: Take the panda, for instance, it has canines but it's an herbivore. However, are there are other aspects of its teeth where one could still tell that it's an herbivore? Do the teeth always relay the information about whether an animal is a carnivore, omnivore, or herbivore?


texts: How to selectively filter BLAST results for an endogenous retroviral LTR to retrieve members of the same ERV family?

texts:
I'm running a local BLAST search on a HERV-K(HML2) LTR sequence in the human genome. I get thousands of hits.

I want to retrieve the hits that correspond to other HERV-K(HML2) LTR sequences only.

What alignment length/identity filters should I use on the hits to select LTRs of the same family? Insertions and deletions could easily alter the alignment lengths meaning the cutoff length for the filter I want isn't clear. I can work out what alignment length cutoffs remove what percentage of the results to identify big drops at specific cutoffs, but it hasn't been very helpful.


texts:
This may be a strange question, but really it's something I've always wondered.
Recently I was watching a documentary of penguins and how a mother penguin lost its child. Then it went looking for it, and among a horde of penguins, it was able to find it's child and take it.
What really intrigued me is that the penguins looked exactly the same. Animals don't have "as much"
distinctive features as we humans do, such as significally different hair color, skin color, they don't really look very different. Rather animals of the same species look very similar.
Just consider the following image:

How can one even differentiate between all these penguin children? Even the parents look very similar.
That's just what I'm wondering. How can parents spot their child between all of these penguins that look almost identical.


texts:
We found this seemingly ornamental plant somewhere in the midwestern United States; does anyone know what it is?

It's fairly low to the ground.  Thanks!


texts:
What is the matrix in the cell, and how does it connect cells together?

I read about this in my textbook. I know that a matrix is the material (or tissue) that connects other cells together. My book says:

  In biology, matrix (plural: matrices) is the material (or tissue) in animal or plant cells, in which more specialized structures are embedded, and a specific part of the mitochondrion that is the site of oxidation of organic molecules.

This wording feels very complex, and I'm having trouble picturing what it's trying to describe.


texts:
Which type of gene does not occur naturally in living organisms?

Bt gene
Endogenous cytoplasmic defense gene

The answer is 2.

I can't find out what this gene is! Does it mean the gene for methylation and restriction enzyme synthesis or some such thing? Does it even exist?

P.s. I am just a student and do not have in-depth knowledge of biotech.


texts: What determines the fate of a cell with respect to differentiation?

texts:
I have been reading about Townes and Holtfreter's work in 1955, in which cells are dissociated from a blastocyst in an alkaline solution then mixed together and spontaneously reaggregates based on type, so epidermal cells around the outside and neural plate cells in the middle.

I understand enough about cell adhesion to understand why the cells will seem to attract cells of their own type, but would like to know how they can initially detect what to become and where they are needed in a specialised form, without something acting like a brain telling them what to become and where to go.

If the selection from the available types is random, as I suspect, what happens to blastocysts with too much epidermal tissue or vice versa? I'm struggling to imagine how organisms like this can develop without something taking the lead and actively coordinating what goes where.


texts: What are the features on a microscope one needs in order to do lab work?

texts:
By lab work I mean urinalysis, blood work(live as well), fecals, cytologies, histologies and all other.

I have read(partly) a book(from 2002) on lab diagnostics and the author did not mention anything about diagnostics. I've spent a lot of time searching on google as well and I did not get anything.


texts: Can someone identify this Brazilian flower?

texts:
The photo was taken in january 2004, at Parque Estadual do Rio Preto (Black River State Park), in the Cerrado (savanna-like) of northeastern-central Minas Gerais, Brazil.

The plant was herbaceous/shrub, but maybe it was because of its tender age?


texts: Difference between Condensin and Cohesin proteins?

texts:
The chromosomal DNA is stacked with help of cohesin and condensin protein in which particular manner? Can cohesin be said to form kinetochore? How would they vary exactly?
The terms are so narrowly windowed that they squeeze my brain through...!!! thank you for your kind help ^_^


texts: Why is reducing the amount of detail required to remember the location of an object in one's environment adaptively significant?

texts:
In Campbell's Biology Chapter 51, question 36 reads:

Which of the following shows the adaptive significance of cognitive mapping to animals that employ this type of learning?
A) It increases the ability to visually recognize landmarks.
B) Cognitive maps reduce the amount of detail required to remember the location of an object in the animal's environment.
C) Animals can locate essential locations in their environment, such as nests, hazards, and feeding areas.
D) Animals can outmaneuver predators by planning and memorizing getaway routes.
E) Animals can determine their position relative to landmarks by a triangulation process.
Answer: B

I answered by saying that Cognitive Mapping is especially important because animals can locate locations essential to its survival (e.g. nests, hazards, and feeding areas), but the answer was B. Why is that more important?


texts: Publicly available resources for learning metagenomics

texts:
We are starting a metagenomics project in our research group to study microbiota in the respiratory tract. Since the are no books yet about metagenomics, seems reading some reviews and online tutorials is the only alternative.

Could you suggest me essential papers, websites or other resources useful for my purpose.

Thanks


texts: Species identification, tree from Ecuador

texts: This tree is recently photographed in Quito, Ecuador. It grows everywhere. I'm new to South American flora, so I'd like to know what the species it is?


texts: What parts of the visual system could be responsible for a fixed, monocular scotoma?

texts:
Light enters the cornea, crosses the lens, hits the retina. Electric sinal travels from retina through the optic nerve, reaches the chiasma, crosses and makes its way to the visual cortex.

My question is: given a fixed, absolute scotoma in one of the eyes, what parts of the vision could be at fault?

Initially, I believe the cornea/lens couldn't be, otherwise the scotoma wouldn't be absolute and fixed. Moreover, I suspect that, after the chiasma, signals from the same visual position are joined, so, the problem couldn't be after it, otherwise the scotoma would be binocular. As such, am I right to conclude that a fixed monocular scotoma could only be caused by issues on either the retina, or on the optic nerve?


texts: How does a cell know what function it has within an organism?

texts:
Given that all cells in a multicellular organism contain the same DNA (ignoring random mutations during mitosis), how does any given cell know what purpose it is supposed to have within an organism.

For example, how does a cell know to become a muscle cell, a neuron or a liver cell?


texts: Limits of brain neuronal spatial mapping

texts:
It is being claimed that brain maps the world space in (roughly) 1-to-1 correspondance of a place to a neuron (link1, link2).

My question is: as the mapping happens in 1-to-1 manner, then is it logical to assume that the brain loses the ability to map space anymore when it already has each suitable neuron assigned to a place?

From these articles, it is clear that the space unit is not very big, and is a sphere of some size not significantly bigger than the body. If the answer to the question is "yes", then what is the approximate size of the world we can map? (any metric would do, be it a volume in liters or surface area in square meters).

Other than that, if the observations described in the articles are lab simplifications, and in real life the mapping mechanism is more complex, then what is it like?


texts: What are the variables that control/influence the color of oranges(Citrus sinensis)?

texts:
I hear that Oranges cultivated in tropical areas of the world tend to be greener when ripe, is that correct?
Even the same type of Orange differs in color if cultivated in California or Florida. I hear that's because of the climate (colder nights == oranger oranges)

But, at the same time, oranges tucked in between the tree leaves tend to be greener, for they need more chlorophyll to make the most use of less access to sun rays.

Could someone correct my assumptions? Also, if possible, list the pigments and processes involved?


texts: Adaptive radiation vs divergent evolution

texts:
What is the difference between divergent evolution and adaptive radiation? People have Said different things
Divergent evolution is when species from a common ancestor evolve differences by adapting to different environmental conditions
Adaptive radiation - species evolve differences due to the different environments
Are they essentially the same thing also I’m confused with the terminology niche
Could someone please tell me the similarities and differences between the two


texts: Why does organ transplant work although it seems organ's motor neuron isn't connected to recipient's CNS

texts: Although it seems impossible with current technology to connect organ's capillaries to the recipient's capillaries and its motor neuron to the CNS, transplanted organ works for years. But why?


texts:
When one loses weight, where does the lost poundage (I assume comprised mainly of fat) go?

Is it urinated out? Defecated out? If a combination of both, does the percentage of each differ depending on how much of what your are losing was pure fat?


texts: Is this arthropod non-intrusive and recommended to be left alive?

texts:
I am in Portugal (Lisbon) at the moment, and when leaving my room late at night (12 pm ~ 04 am) I usually face about 4 of these arthropods in the corridors:

(For reference, the "line" in the image is a standard separation on the floor. This particular example of the animal is a little smaller than a nail.) They seem to have quite variable sizes and walk primarily on ground. Also, as implicit above, they seem to be active primarily during the late night. (I don't see them much often, if at all, during the morning/afternoon.) They can be quite fast, but if left unharmed do not move much. They also appear to take shelter inside the walls.

From what I searched, it seems possible that they are centipedes. I've seen sites saying that they are useful to keep other less pleasant animals at bay. My questions are: What are those animals, and should I leave them be or not?


texts: What is meant by "complexity of carbon sources"?

texts:
My biology book states

  "life on earth depends upon carbon based molecules, most of these food sources are also carbon based. Depending upon the complexity of these carbon sources, different organisms can then use different kinds of nutritional processes"

Please explain this statement.


texts:
I am attempting to microinject small intestinal organoids, using the Eppendorf FemtoJet 4i microinjector and Femtotip capillaries, and have come across several issues. This is a new set up in our lab, and I am first to attempt it so I apologise for the basic questions.

When attempting to fill the Femtotip capillaries using a needle or Western blot tip the liquid backs up and does not fill the capillary, leaving a large air bubble. Is this a common issue with the Femtotip capillaries? Are there other methods for filling (that do not require specialised microloader)?

When I attempted to use a tip where I had let the liquid be pulled to bottom by gravity, I had issues with leakage out of the tip bottom. Just to be absolutely clear, is it necessary for the entire tip to be filled with liquid prior to injection (no air bubbles)?

Finally I would be grateful for any advice on injection pressure and time used for organoids.

Thank you


texts: How can the following data regarding flower phenotypes be explained?

texts:
$$\begin{array}{c|c|c} \hline
\text{Parents} & F_1 & F_2\\ \hline
\text{Blue}\:\times \text{white} & \text{All blue} & \text{196 blue, 63 white} \\
\text{Blue}\:\times \text{pink} & \text{All blue} & \text{149 blue, 52 pink} \\
\text{Pink}\:\times \text{white} & \text{All blue} & \text{226 blue, 98 white,
77 pink} \\ \hline
\hline
\end{array}$$

From the above data, it is likely that this is more complex than simple Mendelian inheritance. My guess is that there is epistasis at play here, but I can’t figure out what is really happening. What are the phenotypes of the parents? What genetic loci are involved and which traits are dominant?

(I was thinking blue ($B$) was the dominant epistatic flower color allele—$BB$ or $Bb$ would give blue regardless of the other color allele, and $bb$ would allow the expression of color dictated by the other gene, which has pink ($P$) as its dominant allele. This doesn’t work, as seen in the third row.)

Can anyone lend their aid here?

(The data was taken from here, question 32 in the sample multiple choice.)


texts: How come the pain in our body, primarily due to excessive physical exercises, vanishes after having a massage? What is the mechanism?


texts: How easy is it to carry out de novo sequence assembly?

texts:
Today a colleague of mine asked the following question:

" Assuming I need to build from 0, a chromosome of a fish, with short reads
but no other reference whatsoever [de novo assembly]:

how much work is that?
Is there a generic software (like SAMtools) that will align the reads in a
scaffold one can use?
Basically, given a reasonably clear pipeline in terms of software, is it still blood sweat and tears or is it just a matter of getting it on a cluster?"

Very grateful for any suggestions, sources of information, software etc.


texts:
From the above picture it can be seen that, in the region "B" the activity of enzyme is not proportional to the substrate concentration.

Why don't we achieve enzyme saturation linearly? Why do we go through that curved phase( region B )?

Why don't all enzyme gets saturated at a point?


texts:
Is there any database that contain binding affinities reported in litterature for different proteins and ligands?

I have checked uniprot already and it does not seem to included any binding affinity data, for several well characterised receptors such as the human insulin receptor.


texts: How does antagnostic coevolution work in ducks?

texts:
I recently learned that in ducks, the penis and vagina have coevolved: the vagina of the female ducks gets dead-end sacs and clockwise coils; the penis of male ducks become longest and its morphology changed to adapt to the female vagina. [1] This antagnostic coevolution happened due to the evolutionary arms race between male and female ducks.

This seems counter-intuitive when we think about natural selection. Indeed, if female ducks are forcibly copulated, they are more susceptible to reproducing themselves and sharing their genetic traits.

From  [2], it appears that only 3% of forced copulations results in fertilization. If this is the case, why has the male phallus evolved this way? Indeed, it does not appear to me to be a good evolutionary strategy.

If [1] and [2] are correct, I would think that the duck vagina and phallus shouldn't have coevolved that way. What am I missing?

[1] Brennan, P. L., Prum, R. O., McCracken, K. G., Sorenson, M. D., Wilson, R. E., & Birkhead, T. R. (2007). Coevolution of male and female genital morphology in waterfowl. PLoS one, 2(5), e418.

[2] Burns, J. T., Cheng, K. M., & McKinney, F. (1980). Forced copulation in captive mallards. I. Fertilization of eggs. The Auk, 97(4), 875-879.


texts: I got this tortoise from my uncle. He said that it wandered into his yard. Found in Khon Kaen, Thailand during the summer.


texts: Do invasive species survive in the long run?

texts: If an invasive species preys on native species, spreads widely and becomes dominant, should it not become extinct soon enough because of a lack of food?


texts: Programs/software to graph biological data

texts:
I am curious about what sort of programs people in my field of academia are using to graph their data. I am a master student in biochemistry, and have more or less only used excel (on rare occasions I have used the statistical program R).

I know my question is very general, but I would like to hear suggestions for programs that could be useful when I want to compute numbers or make good graphical representation (in the life science fields, e.g. microbiology, biochemistry, biotechnology, biophysical chemistry).

Also, are the other programs to create good graphic illustrations? I am currently using Inkscape to produce molecular illustrations, and I think this is one of the most typical programs to use?


texts:
Please help identify this insect - genus, species and anything interesting about it.

(Part of this old thread.)


texts: What is the difference between drought resistant non-succulent plants and plants that cannot be allowed to dry out?

texts:
What features make one plant able to withstand dry spells better than another with relatively similar structure? For instance, one of my Rudbeckias is wilting from drought at the moment, and an Oenothera next to it is not yet showing signs of dryness.

Or like jewelweed (Impatiens capensis), which wilts even while the soil is damp, in full sun, and ragweed (Ambrosia artemisiifolia), which will grow in very dry locations without being phased.

Is it caused by a faster transpiration rate in some plants than in others?


texts: Can translation ever occur without transcription?

texts: This question is aimed mainly towards viruses with ssRNA, is transcription required, for the +ve strand RNA? If so, why?


texts: Bug Identification: Is this small tubular, black bug a bed bug?

texts:
So I found this tiny bug on my wall in the bedroom of my apartment. I estimate it is about 3mm long by 1mm wide.

Is it a bed bug?

It does not seem to match any of the pictures I've seen online.

The apartment is very clean by most standards. The only other bug I've seen in here is the odd stink bug.

Northeast coast of USA.


texts: Is liver the only internal organ in human body with regenerative capacity? How about endometrium?and what is the difference between regeneration and renewing?


texts: What does localization of B-Cell mean?? "Localization of B and T cell in allergens may not coincide". What does this statement mean? (I have not studied biology since last 8 years and now I am going through it because I need it for my research. So if someone can describe it in simple language it would be very helpful)


texts: Influence of carbon dioxide concentration on the rate of photosynthesis

texts:
The experiment to prove that carbon dioxide concentration influences the rate of photosynthesis:
Click here to see the image

The experiment is repeated after adding some sodium hydrogencarbonate (which dissolves in water to produce carbon dioxide) to the water. It is observed that more oxygen bubbles are produced, and thus this shows the increased photosynthesis rate.

My question: The equation for the dissolution of sodium hydrogencarbonate is NaHCO₃ (s) ⟶ NaOH (aq) + CO₂ (aq). But won't the sodium hydroxide turn the solution basic and also influence the rate of photosynthesis?

Thanks in advance,
Ramana


texts: Why do more complex DNA strands take longer to anneal?

texts:
My textbook and several websites told me that more complex DNA strands take longer to anneal because it is harder to find the correct sequence. A simpler, repeating sequence like ATATATATA would be faster to anneal since it would be really easy to find a spot to reanneal.
I kind of get the logic here. Yet, this wouldn't always produce the exact complement strand. Consider the following:

The point is to illustrate that there could be matching of strands without correctly pairing the whole thing (i.e. there is a shift of the strands).
This means that if you want to fully anneal the strands, you need to find the correct spot in the second strand to begin annealing - which is no better than if these were completely random strands.
So then, why is annealing more complex strands slower? I've tried searching it up on the internet but all I get are people telling me it is true, and without much of an explanation.


texts: What mechanisms exist for the excision of specific sequences from DNA?

texts: I already know about recombinases (specifically excisionases), but was wondering if there were other mechanisms present.


texts: High-res / high quality, public domain cell / bacteria images on the web for download

texts:
Wondering if there are any high quality, high res images of eukaryotic cells or bacteria on the web available for download (public domain). I found some illustrations which are public domain, they look nice, but they are illustrations. I would like to find SEM electron micrograph images or things of that nature, microscope images in the public domain.

Here is an SEM image that is somewhat acceptable, though it has the legend built into the image and isn't colorized (colorization would be a bonus). Here is a colorized image.

This is more the quality I am looking for.

This is decent, but it's not public domain.

These are great!

I wish some of these were public domain.


texts: Why do we see colours when we close our eyes and press our hands against them?

texts:
Whenever we close our eyes and press our hands against them we either see some colours or sometimes some weird patterns(similar to hypnotic patterns).
What is the cause of this phenomenon?
Also, is this the right place to ask this question? Does this question have more to do with biology than physics?


texts: My textbook (Physiology 9th edition, People's Medical Publishing House, Beijing) tells me that coagulation factor V is produced in endothelial cells and platelets, which is different from some other books (saying in liver). So where exactly is it produced? Or is it just not quite clear?


texts: Differences Between Protein Motifs and Protein Domains?

texts: I am in a 300-level molecular biology class and am unclear about this concept and how to delineate motifs versus domains of proteins.  Any suggestions would be much obliged.


texts: What is the difference between using an open or a closed configuration for a microfluidic chip?

texts: I am doing a college BioMed project on Lungs-on-a-chip to make disease models and I have seen some authors use open configurations, while others use closed configurations. What advantages and disadvantages do they offer on the making of this device?


texts:
I have a problem with my proteomics homework. I was asked to design primers used to create a homologous recombination box to create PRP24-TAPtag yeast. I know that homologous regions should be 40-50nt and that my primer should include overhangs. I was told to base off of this publication:
https://www.ncbi.nlm.nih.gov/pubmed/11403571

I have designed primers before, but this time I have encountered really big problems. I have found both my plasmid, pBS1479, TAPtag and PRP24 protein sequences, but I have no idea how should I join them to create primers and how to include the TAPtag. This is my first time using this method. Are there any tools I can use for this task?
Should I add tag sequence to C end of my protein, then use plasmid seqence to create overhangs?


texts: How to decide if genes are linked in an unordered mapping problem?

texts:
From what I understand, if the tetrads resulting from a cross exhibit the same number of parental ditypes as there are nonparental ditypes, then the genes under consideration are said to be unlinked.

For example, say I cross two gametes containing $ab^+$ and $a^+b$, respectively, and get 170 tetrads exhibiting parental ditype (all offspring are $ab^+$ or $a^+b$), 165 exhibiting nonparental ditype (offspring are $a^+b^+$ or $ab$), and 30 exhibiting tetratype (offspring one of $a^+b^+$, $a^+b$, $ab^+$ or $ab$).

I'm not sure whether to classify these genes as linked or unlinked. I want to say yes, they are indeed linked, but 170 and 165 seem like close enough numbers to suggest they may be unlinked.

I would think the ratio of parental to nonparental ditype has to be considered close enough to 1, but how do we decide a threshold for that?


texts: How did the moray eel evolve a pharyngeal jaw?

texts:
I am referring to the retractable second set of jaws in the moray eel.

How can one imagine such an evolutionary step to have occurred? Just by chance an eel grew a second internal jaw and it was luckily attached to some muscles which made it useful for swallowing prey?


texts:
I have read in my biology book that

  "nastic movement is the movement that occur due to difference in the rate of growth on two opposite sides of a plant organ" ,

but I can't visualize how this movement take place and how the rate of growth cause this movement?


texts: Types of structures formed by various types of lipid molecules

texts: Since Phosphatidylcholine (PC) and phosphatidylserine (PS) are roughly cylindrical in shape , they tend to form bilayers. Phosphatidylethanolamine (PE) on the other hand is conical in shape which bends the lipid bilayer when present asymmetrically along with PC and PS. What kind of structure will form when PE is present exclusively?


texts: Why do some reflex actions involve interneurons, but some don't?

texts: According to what I know, the reflex arc of knee jerk reflex doesn't involve interneuron, but other reflex action (e.g. removing your hand when touching hot things) do involve interneurons. Why is that the case?


texts: Help identifying a mushroom found in Raymond, WA, USA

texts:
Hello dear mycology wizards!

Could you help me figure out what's the name of this species.
I found the mushrooms in a forest near to Raymond, WA. The area was quite wet and mossy, but not a swamp. There was a creek ~50-75 feet away. The forest is mostly coniferous trees with a few birches.

Here are the photos of the mushroom of interest:


texts: What is the difference between silent and synonymous mutations?

texts:
Several sources all caution that silent mutations and synonymous substitutions are not the same thing and should not be confused. But they seem to draw different actual distinctions between the terms:

This Wikipedia page and this biology dictionary entry define a silent mutation as a point substitution that replaces a single codon by another codon that codes for the same amino acid, and therefore does not directly change the amino acid sequence that is coded for. It defines a synonymous substitution as a silent mutation that occurs in an exon. Under these definitions, a synonymous substitution is a special case of a silent mutation.
This Wikipedia page and this blog post define a silent mutation as any mutation that does not have any phenotypic effects, and defines a synonymous substitution as a point substitution to a degenerate codon (anywhere in the genome, as far as I can tell). It points out that such synonymous substitutions can still have indirect phenotypic ("nonsilent") effects by affecting translation and transcription. Under these definitions, a silent mutation is a special case of a synonymous substitution (namely, one that doesn't have any indirect phenotypic effects).
This Wikipedia page uses similar definitions to the one in #2, except it explicitly requires that a synonymous substitution occurs in an exon.

Clearly these definitions are not all compatible. (#2 and #3 are very similar and could perhaps be excused as minor variants on the same definition, but they clearly conflict strongly with #1 - they disagree on which of "silent mutation" and "synonymous substitution" is a special case of the other!) Is there a standardized distinction in the biology community between these terms, or is it just the case that everyone uses conflicting definitions and we should ask people to clarify the senses in which they're using these terms?


texts: I can't Identify this "bug" that seems attached to fresh cut wood

texts:
I'm a very amateur entomologist (I'm actually just an old fat hippie that loves all critters).

I don't have any chops here, but I swear I've done my due diligence and tried to figure this out. I'm asking because I'm baffled. (Leg stripes are Arachnid-ish, but thorax is completely wrong ... I just dunno...)

My girlfriend sent me a pic; she swears these things were jumping out of a seasoned firewood pile and by her words "attacking".

Location:  PA Pocono mountains, circa Kunkletown, heavily wooded area.

Now granted, there was a lot of drinking going on, it was "girls weekend out", and there was a hot tub.  I wasn't there; so I cannot actually confirm what really happened... (Of course I wish I was there, but ... nevermind)

HOWEVER - here's a pic.  You can't make this up.  Or, at least, I'm not making this up ...

What is this critter?  I think it's "insect" by the leg count I can see.  But edumicate me; this is a new one to me and I'm very intrigued.

Many thanks best!

On Edit

Perhaps some sort of "wood cricket" based on rough taxonomy of the leg configuration, and it's penchant for jumping.  Pure speculation.


texts: Effect of myelination on inteligence in cephalopods

texts:
Cephalopods are known for their unique intelligence compared to other invertebrates.
The number of neurons of cephalopods is of the order $5*10^8$, similar to dogs. Humans have about $10^{11}$ neurons.

However, a major difference between cephalopods and humans and most vertebrates is the lack of myelination of their axons. Instead, to quickly transmit signals, cephalopod axons are much larger, reaching sizes of up to 1mm.

If we could edit the genome of an octopus, so that its axons are coated in myelin similar to a humans axon, whilst retaining their size, would this change the intelligence or behaviour of the octopus because of the increased processing speed?

Edit:
This is a repost of my original questions, to better conform with the guidelines of this forum. I am new to both this site and biology. Thank you very much for reading.


texts: Evolution of sexual reproduction from asexual

texts: How exactly did asexually reproducing organisms evolve into sexually reproducing ones? Why was it considered more favourable?


texts: High sequence similarity but start codon isn't methionine

texts:
I have noticed in a particular genome sequence of a prokaryote that various regions in a sequence share similarity which is high(>80%) with known proteins. However, the start is not a methionine. Is this a dysfunctional 'protein' sequence? Or are there alternative codons which translate those regions without a Met or fMet for that matter?

Technically, do all annotations of proteins have to start with a methionine?


texts: What is the scientific name of such a fungus?

texts:
Several days ago, in a bush I found the fungus as attached which is about 25cm in height and does not look like an edible mushroom:

Any one has an idea of its scientific name and other details?


texts: Before Evolution was proposed by Charles Darwin, what were the leading secular theories to explain how life developed?

texts: Outside of evolution, what were the leading scientific schools of thought that Charles Darwin contented with when he published his evolution theory as way of natural selection in 1859?


texts: Is Sanger sequencing still used in labs, and therefore worth learning?

texts: If iI were to have access to funds for research, would learning this technique be a boon for me? Or are next-gen sequencing methods all the range now? My knowledge of both are limited.


texts:
This Scientific American article states that "[human] infestation [by bacteria] begins at birth". This would suggest that unborn babies are free from any bacteria. However, if the mother catches a bacterial infection, her unborn baby risks catching it, too. This would seem to contradict the Scientific American article.

Presumably, when a human egg is fertilized by a sperm, the resulting cell may be free of any bacteria. At some point, bacteria begin to colonize the growing human body. Which bacteria are the earliest to colonize, and at what point in the development cycle does this occur?

In particular: does the health of the foetus depend on the presence of certain bacteria?


texts: why are malarial parasites specific for anopheles mosquito. why do they need only anopheles, they just need lower temperature to complete their life cycle. all mosquitoes are cold blooded, so they can get a suitable environment in any of them, why only anopheles?


texts: Parts of the brain pivotal for maintaining consciousness

texts:
From an answer to another question (on conscious experiences by coma patients) I have learned that

  no conscious experiences, complex thoughts, or complex emotions can
  occur when one is in coma (clinically unresponsive, with absent or
  minimal brainstem reflexes, and with severely abnormal EEG)

This means that proper modes of activity of the cortex and the brainstem are necessary conditions for conscious experiences.

Two questions arise:

Has it been shown that proper activity of the brainstem and the cortex is also a sufficient condition for conscious experiences, i.e. all other parts of the brain might be mute or otherwise improperly active? Or are there other parts of the brain whose proper activity is also necessary for conscious experiences?
Why is it that next to the newest parts of the brain (cortex and neocortex) also its oldest part (the brainstem) is pivotal in maintaining consciousness? What about other parts that evolved later?

Note that with "necessary" I don't mean causally necessary but merely logically or observationally necessary, i.e. "not observed without".


texts:
In my house there's a strange plant that I see growing for years now. I believe it is a climbing plant. Do you know how is this plant named? Is it poisonous?

Location: Greece

Altitude: 800m.


texts:
My daughter has become one with nature somehow and came across an odd looking caterpillar. The odds of finding one never found before is great,  however I'm unable to find what kind it is. It's head is bright red.

From Eastern North Carolina, USA.

Would anyone be able to point me in the right direction?
Thanks!!!


texts:
A scientist from Harvard, David Sinclair, has a few videos, a book and some papers on the topic of ageing. Particularly, I've seen this video a couple of times where he explains their discoveries on the biochemistry of ageing.

The first part of the talk (min 6 to 20 or so) is about why do we age,
the rest to how to reset ageing.

As to why do we age, he postulates it's because of broken chromosome(s) disrupting the spatial structure of DNA/other chromosomes, and consequently the expression of genes.
[The chromosome-lysis could be due to UV rays or ROS, or any other cause.]
He also claims methylation has to do with ageing and that it is a measure of ageing (18:00). But DNA methylation is a mutation and is changing the DNA sequence more than the epigenome.
My question here is: Is chromosome-lysis actually proven to be the main factor why we/mices age? How does methylation fits here?


texts: What are the advantages and disadvantages of being ambidextrous?

texts:
Most of us have one dominant hand. We find it nigh on impossible to do very delicate or dextrous activities with our other-hand. This seems like an apparent weakness, and a rather odd one when you first think about it.

Cursory internet searches revealed unexpected findings. One website said it has mostly negative effects on the brain. However I don't trust the source at all.

I'd be interested to know about the "story" about the good and bad of ambidextrous physiology. Particularly, I am interested in the neuroscience of ambidextrous people.


texts: Which part of the brain needs to be shut down to lose conciousness?

texts: Whether it is mechanical (trauma), chemical (anaesthesia) or electrical - which part of the brain is shut down to cause loss of consciousness?


texts: When there is 'excessive' cell growth 'ordered' by the human body in some specific part of the body that is not part of the usual repairing mechanisms, does this cause extra telomere 'shortening' or damage even though a lot of cell growth and repair is 'required'. If a lot of cell growth is 'activated' with problematic telomeres does this cause telomerase to be formed which then might shut down the apoptosis mechanisms and keep the cell 'going' indefinately. Note; I read some acid reflux problem causes parts of the throat to scar or be damaged causing excessive cellular repairs on those parts of the throat where tumors have later developed. When someone gets sunburned on the shoulders say, and this damages the skin there, then does every future time the persons shoulders get in the sun ,do those same areas get further damage causing excessive growth and repair of skin cells on the shoulder. With a lot of excessive repair tumors might develop. SO could excessive cell growth (that might be caused by many different factors ) help to cause cancer??


texts: Standard notation for dominant and recessive allele

texts:
I'm reading through some science that could come up in my GRE equivalency.

I've never been much of a biologist, more of a chemist/geologist....though it does interest me massively!

I'm just seeing this question in a textbook....

Q) Assume eye colour in humans is controlled by a pair of alleles of a gene where the allele giving brown eyes is dominant to the allele giving blue eyes. Both parents of a blue eyed man, John, were brown eyed. He married a brown eyed woman, Sara, whose father had brown eyes and mother blue eyes. Sara had a blue eyed sister. John and Sara had a brown eyed child.

Fill in the boxes and circles on the family tree below to show the genotype of each individual.

I just wanted to ask how exactly we mark out genotype in science? Do we use D's and r's?

Thanks!


texts: It is on my bed sheet. The hairy part the the rear end. The length is about the diameter of a US dime (~18mm).


texts: How to annotate the SwitchGear gene models?

texts:
According to this page(http://switchgeargenomics.com/wp-content/uploads/2009/02/switchdb_technote1.pdf), the SwitchGear gene models can be annotated by the NCBI annotation associated with Refseq accession numbers, but I couldn't find such information in this page(https://www.ncbi.nlm.nih.gov/refseq/), which is indicated in the above pdf page...

How can I annotate the SwitchGear gene models?


texts: What is the "leaky valve" between the esophagus and stomach?

texts:
When someone talks about there being a "leaky valve" between the esophagus and the stomach, what is the exact biological structure they are talking about?

This would be a structure that, when malfunctioning, causes stomach acid to leak into the esophagus.


texts:
Identify this beetle from Bangladesh
Location: Bandarban, Bangladesh


texts: How long would you expect a designed plasmid to remain in a population of E. coli after transformation?

texts:
When transforming E. coli with a genetically-modified plasmid, how quickly/often is this plasmid "lost" because of mutation, or horizontal-transfer, or "dilution" over reproduction over several generations?
How often are inserted plasmids lost/mutated/diluted in E. coli? How long would you expect to observe the plasmids' output after transformation?


texts:
Just like the title says: Strictly from a biological perspective, what is the functional expectation of a human being.

No religious or philosophy-based answers will be accepted, we are talking biology not religion or philosophy.

Answers involving excessive psychology will be frowned upon unless found to be exceedingly insightful. (The brain is a biological entity)

If you are considering claiming this to be too broad or unanswerable consider the hypothetical question "what are the functional expectations of human feet" which can be answered fairly easily by a child with no formal training in biology. In my actual question I simply ask about the feet and the other parts attached to them.

Edit: Originally this question was titled "Strictly from a biological perspective, what is the purpose of a human existence." To clarify the question i have changed it to "Strictly from a biological perspective, what is the functional expectation of a human being."

Despite the concerns raised with the use of the word "purpose" the question was serving its purpose with the answers I am seeing.  I did have  some reservations about the word "purpose" as well, but I thought I would try it and see what others thought.

So if a human stomach has the overall functional expectation of mechanically and chemically breaking down and digesting food, what would be the overall functional expectation of a human as a whole? I am looking for not so much of psychologically specific functional expectations and more of physical functional expectations.

For instance a house cat's functional expectations are generally considered to be sleeping, eating, reproducing, socializing, hunting, etc.


texts:
I used to think that a DNA clamp is a protein. But today I noticed it doesn't appear in this picture. Then I went to it's Wikipedia page, where it was written:

  A DNA clamp, also known as a sliding clamp, is a protein fold that
  serves as a processivity-promoting factor in DNA replication. As a
  critical component of the DNA polymerase III holoenzyme, the clamp
  protein binds DNA polymerase and prevents this enzyme from
  dissociating from the template DNA strand. The clamp-polymerase
  protein–protein interactions are stronger and more specific than the
  direct interactions between the polymerase and the template DNA strand

Which I find a little confusing. For now it seems to me like DNA clamp is a subunit of DNA Polymerase and it doesn't have any function by itself and it is not an actual protein but it binds to Polymerase and becomes functional. Can somebody please clarify this matter to me?!


texts:
In Darwinian evolutionary theory, does the environment has any role?

To state it clearly:

Suppose I have an isolated system. First, I place several types of entities (organisms) in an environment. According to Darwin, eventually, the fittest will survive.

Next time, I place Only one organism. Will it survive this time as there's no one else in the system?
If not, did Darwin also consider the whole environment as another entity, so that in the above case, there are two entities, the organism and the environment. The environment is more evolved and it survives, other dies?

Moreover, if the climate is favourable and the organism reproduces sexually results in the same fate as the case if climate is unfavourable, organism reproduces asexually, what conclusion does it leads to?


texts:
Last night I was drying my cat with a towel after shenanigans in the rain and she sneezed!

Questions

Can cats/dogs/hamsters or other pets catch the cold?
How quickly do they recover?


texts: Is the number of stamens always 9 for geranium?

texts:
We are studing in class the reproduction of plants.
We start the lesson by observing some components of flowers, it was the Géranium.

First of all we start counting the number of sepals , petals and stamens.
The problem is that I found:

5 sepals

5 petals

9 stamens

and every other student found that the number of stamens was 9 or 8 or 10.

I asked my teacher and he says that he counted the number of stamens many times and he found 9.

Is it really 9? Do the number of stamens is depending of the number of sepals or petals? Is there any relation ?


texts: Does anybody know what kind of snake is this?

texts: FYI the snake is dead and currently in my freezer, I got it from a guy and forgot to ask what kind it is.


texts: How we can localize sound vertically (up-down) and front-to-back?

texts:
It is quite simple to understand the concept of lateral localization of sound. It depends upon the loudness and time (and wave phase) difference between 2 ears.

But how can we detect front-back localization (if someone is calling me from my front/back direction) and up-down localization (such as an aeroplane's sound is coming from upper place and a car's whistle is coming from lower-direction of the balcony I'm standing). How does that happen? Or doesn't localization happen at all under these conditions? Is it just an illusion just because we are already aware about the possible source (such as since it is aeroplane's sound then it might coming from upward place, or I can see my friend is talking by standing my front so the sound must coming from front... etc.)

I've searched wikipedia and other sites, but I found nothing that explained the matter sufficiently.


texts:
I hope this question fits here, I haven't found another community where it would fit.

Two years ago I was in a hotel in Sri Lanka (south-western coast) and in the hotel gardens there were a lot of squirrels. From what I could find out, they probably were Indian Palm Squirrels, but I don't know for sure. They were striped.

They were very tame and come to the hotel guests, hoping they would get something to eat. You could even touch some of them, so they are probably used to that.
We fed them some roasted peanuts (unsalted) and they were pretty happy about it, sometimes they also just took them by themselves =)

My question is, as I am about to visit the same hotel again this year, is it safe to do so? I know that they mainly eat nuts, fruits and insects, but our nuts were purchased in Germany (though propably imported from elsewhere anyway). Is there any danger for the squirrels or is it a terrible idea to feed those wild animals anyway or is it fine to do so, as long we don't cram them?


texts: Bending your little finger without bending ring finger

texts:
It is possible to bend each finger without bending any other, except one for most people. It is more difficult for the ring finger, but when I try to bend my little finger independently my ring finger bends as well. I don't know if this is because of the muscle or  bone configuration, but I'm interested in the answer.

  Is it possible to bend the little finger independently, and if so why is it so hard to do so?


texts: Measure of environmental impact on phenotype

texts:
Let me begin by disclaiming that I am nowhere near a biologist by competence or education and that I am simply interest in some of its fields of study as a matter of general curiosity. So excuse my ignorance.

I've been recently pondering the concepts of genotype and phenotype. This page succinctly summarizes the difference between the two.

I was curious if there are scientific measures, and how accurate they are, for the impact of environment on the phenotype of a specimen. Hypothetically, if the environment had no effect, the phenotype would be 100% determined by the genotype. But, in a simple approximation, phenotype = genotype + environment. Does modern biology have a measuring system for how much the environment affects the ultimate observable features of an organism, on top of what its genotype does?


texts: Are mitochondria transferable between cell types, individuals and species?

texts:
I'm curious about what happens when you insert organelles from a cell into another. In particular, mitochondria.

Take two cells from your own body. Somehow extract a mitochondria from one cell and somehow insert it in the other cell.

Will the cell with the foreign mitochondria make use of it (respiration), or will it dispose it?

What if the foreign mitochondria comes from someone else's body?

What if the foreign mitochondria comes from another species' cell?


texts: Are fluoroquinolone antibiotics (Cipro, Levaquin, etc) chemotherapy drugs?

texts: I read a claim (I can't find the source) that fluoroquinolone antibiotics are actually chemotherapy drugs, or maybe to be more specific, are "chemotherapeutic." Is this claim true? Additionally, if true, does this claim apply to all antibiotics, or only fluoroquinolones?


texts: Shell-less Chick development - Incorporation of Calcium carbonate instead of Calcium lactate pentahydrate powder?

texts:
I'm a college undergrad biology student and currently studying developmental biology as part of my curriculum.

I've read a research journal titled, A Novel Shell-less culture system for chick embryo using a plastic film as culture vessels. by Yutakah Tahara and Katsuya Obara, and happened to be interested with this method but stumbled with a question that kept bugging me out of pure curiosity. While reading their journal I encountered a statement

"...250-300mg calcium lactate pentahydrate powder (Showa Chemical Co., Tokyo, Japan) was added to the culture vessels." and they also added distilled water.

The proponents seem to use Calcium lactate pentahydrate as a substitute for the chick's source of calcium. In dev bio class, I've learned that the chick embryo has two main sources of calcium - the yolk and the egg shell. The egg shell contains 94% Calcium carbonate (literally a major source of calcium). I've read that the Chorioallantoic membrane (CAM) is responsible for the mobilization or transport of calcium from egg shell to the chick's circulation -https://www.ncbi.nlm.nih.gov/pubmed/2955074 - and here is where my question starts:

I understand that the proponents used Calcium lactate pentahydrate powder because its soluble in water - making it easier for the chick to incorporate the dissolved  Calcium lactate. I also understand that Calcium carbonate is insoluble in water BUT If CAM is responsible for the mobilization of calcium from egg shell to the chick's circulation to form the skeletal structure of the bird, what difference does it make if I use sterilized powdered egg shells as the chick's 2nd major source of Calcium carbonate?

Thank you for taking the time to read and trying to answer my question! It means a lot


texts: How to teach my self Biology and Chemistry?

texts:
Long story short I'm a American dreamer (a immigrant brought to the USA as a child but is illegal) and recently returned to my home country and not knowing the language here have had a hard time at school I am now 22 and think I can finally get somewhere I just need to teach my self Biology and Chemistry (Childhood dream was to be a biologist of some sorts) but I don't know where to start.

Can anyone recommend and books how how I should start my studying? I need to learn this stuff to be able to get into a university here. I wan't to start from the start and work my way up to University level.

Any sort of help would be greatly appreciated

Thank you in advance

Edit: TLDR: Basically I'm asking how I can home school my self to learn Biology and Chemistry to be able to get into a University and learn Biology and Chemistry on a University degree.


texts: Do all restriction enzymes have palindromic recognition sites?

texts:
I am trying to find out the requirements for a segment of DNA to be the recognition site of a restriction enzyme.

Acording to the article on Restriction Enzymes in Wikipedia, "many of them" (referring to recognition sites) are ‘palindromic’ (in the sense that the sequence of nucleotides on one strand should read the same as the that on the other strand, from the opposite direction).

Is this true for all recognition sites?


texts: Could an action potential produce few or more neurotransmitters based on the stimulus received?

texts:
I reckon that if you would be able to widen the AP width, it would produce more neurotransmitters in that larger time interval. Is that correct? Or does the neuron have a standard amount of neurotransmitters it releases in order to pass the signal post-synaptically?

(bonus: could it NOT result in neurotransmitter release, or does the definition of an AP include the release of neurotransmitters?)


texts: Why does milk contained in cartons of milk expand?

texts: In the morning, I went to the fridge to drink some chocolate milk. At night, when I took out the same carton of milk, the packaging seems expanded, like some kind of air is inside. Explain please !


texts: Why do flowers naturally reproduce with their own species?

texts: I have always wondered why flowers reproduce with the same species naturally. Why can't the pollen grains get to a different species flower through via the wind, water, or insects?


texts: Have I identified this species correctly? Weird ocean blob

texts:
I often comb the beaches in Santa Cruz (central California coast) for weird stuff that washes ashore. The waves have been a lot stronger than usual the last few days, and the today the beach was covered in a thick layer of kelp and other seaweed. There were even two dead seals washed up on the sand. Most intriguing however was this translucent oddity:

Reverse side:

It's about two inches across at its largest. I moved it to a concrete wall to photograph so I could turn it over without coating it in sand, but I found it down much closer to the water. It seems all but certain that it was ripped up from the seabed. I think there's a tiny snail attached to it, visible in the first picture.
Having done some digging, my best guess for the identity
of this species is some kind of ascidian tunicate. The closest comparison I find is this picture of Ciona intestinalis:

due to the orange hue and the distinctive black cord running through it. However it seems much fatter and I didn't notice a siphon on my specimen. Additionally, most images of the species show a much paler color and even more prominent siphon. My specimen might have shriveled from being out of the water though.
So, my guess is Ciona intestinalis. Can anyone confirm or refute?


texts: How can a disease be transmissible animal-to-human but not human-to-human?

texts: I have heard some debate about whether or not the Wuhan virus can be transmitted human-to-human, but this doesn't make sense to me.  Why wouldn't it be able to?  Are there diseases that can only be transmitted from animals, not humans?


texts: Can photosynthesis take place if the plant is kept in ice cold water or not?

texts: Can photosynthesis take place in a plant even if the plant is kept in ice cold water? I have googled this question, but so far have not found a satisfactory answer.


texts: Which test can be used to diagnose typhoid fever

texts: The only thing I found was the widal test, which is no longer an acceptable clinical method. I can't find much information about this anywhere else other than the test needs to analyze samples of blood, poo, and pee. Is there a specific name for this test?


texts: What causes REM atonia to be lost in sleepwalking?

texts:
I understand that in normal REM sleep the voluntary muscles are in effect paralysed in order to prevent an individual acting out their dreams.  This paper indicates that there are likley to be multiple causes of this atonia. I am interested to know what are some of these methods by which natural atonia is achieved by the body in periods of sleep?

Furthermore, what causes these mechanisms to fail in individuals who suffer from sleep-walking?


texts:
I want to make a sound recording of an ant colony located in a wood pile in a German forest (I don’t know the exact species).
To optimise this, I would like to select a time for this when the ant colony is at the height of its activity, i.e., loudest.
My naïve guess would be that noon in summer with some time after the last rainfall is best, but I could find anything to confirm or go beyond this.

Thus I am asking: When is an ant colony loudest, more specifically:

What time of the year?
What time of the day?
What weather conditions?


texts:
Like the title says, I am looking for a good introductory text to histology. It would ideally cover

sample preparation
microscopy
staining, and
several example experiments

Suggestions?


texts: Seeing new colours with new photoreceptors

texts:
If we developed new "eyes" that could see "non-visible spectrum colours" and connected them to our brains, would our brain be capable of identifying and interpreting those new colours? Is our brain hardwired to only de-encode information about RGB using our SML cones?

How is color information transmitted from the eye to the brain?
Our brain receives the information as an FM signal, but does that mean a different "carrier frequency" is used in the FM will the brain detect and interpret this new colour?

Cerebral activity during exposure to non - visible light
We lack the ability to see colours outside of the visible-spectrum due to a lack of photoreceptors.

https://www.quora.com/Why-cant-we-think-of-a-new-colour-Is-it-really-impossible-to-think-of-any-colour-that-doesnt-exist-right-now-Is-the-light-spectrum-the-only-possible-source-for-new-colours-or-might-there-be-something-else Note that this link states we can "imagine" new colours in a pseudo kinda way.

The two points I found online providing information about my question: Yes adding new photoreceptors/sensors to our eyes could be a way to see new colours and yes sending a different signal would seem to be the way to interpret a new "colour". But those answers only partly apply to whether it's actually possible and only narrowly approach this question.


texts: Comments on Experimental result regarding Anti-Bacterial soap

texts:
After using soaps, we rinse our hands with water.

Do bacteria from the water attach themselves to our hands again?

If we wipe our hands to cloth after washing our hands, do bacteria from the cloth also attach to our hands?

Or, do antibacterial substances remain on our skin and, in a sense, 'protect' us from bacteria in a given amount of time?


texts: What would happen if VEGF was injected into a person?

texts:
Couldn't VEGF help with ligament recovery? I looked it up and found some studies in rats, but nothing on people. VEGF inhibitors tend to be used more often then VEGF.

Why isn't VEGF being used in people? What would generally happen if VEGF was injected into a person?

EDIT
Here is the one study that examined injection VEGF in rats for increasing skin viability.

Also I am not really asking about the effect of VEGF on ligaments. I just figured that because there is little vasculature surrounding ligaments (and cartilage), VEGF could in theory improve recovery of such injuries. The bigger question is why aren't people ever injected with VEGF?


texts: What is the definition of the life biologically ?

texts: I want to know what is the definition of the life biologically , on the other hand ,  what is the definition of the death biologically  ?? However, I think it is a very difficult question to answer .


texts: Meowing for kittens is similar to a baby crying. As human adults grow, they stop crying, but as kittens grow up they continue to cry. Why is this?


texts:
This YouTube video shows a bird which appears to repeat some sounds (not speech though) after a human. Here're some cropped screenshots from the video:

What species is this bird? Can it actually mimic human speech, or are these sounds in the video its natural sounds?


texts: identification of differentially expressed genes in RNA-seq analysis

texts:
I am using four different packages (viz. EBSeq, DESeq2, edgeR, LPEseq) for identification of differential genes. Now I am confused whose fold change value should I take for further downstream processing.

Please give your suggestions.

Thanks in advance.


texts: What is the optimal sampling method for modeling of microalgae growth?

texts:
Recently, I am performing microalgae (Chlorella sp.) cultivation experiments for the mathematical modeling of microalgae growth with respect to time.

The main issue is that an analysis of lipid contents in microalgae requires a large volume of culture media per data point. Especially, in the early stage of the cultivation, the density of the microalgae is very low, so almost 20% of the total culture media needs to be consumed for obtaining just a single data point. Due to this limitation, sometimes, I measured only three times (the beginning, middle, and last).

More data points are obviously desired for the accurate modeling but it ends up with huge loss of the media. This may affect the quality of the overall experimental results. This seems like a sort of trade-off. The problem is that I cannot increase the size of the reactor volume at the moment.

Could anybody recommend how to come up with the optimal sampling number in this situation?

Any experience, ideas or recommended papers are welcome.

Thank you.