Instruct: Given a question, retrieve documents that can help answer the question.
Query: What hormone is responsible for human growth?
Genes for human growth hormone, known as growth hormone 1 (somatotropin; pituitary growth hormone) and growth hormone 2 (placental growth hormone; growth hormone variant), are localized in the q22-24 region of chromosome 17 and are closely related to human chorionic somatomammotropin (also known as placental lactogen) genes. GH, human chorionic somatomammotropin, and prolactin belong to a group of homologous hormones with growth-promoting and lactogenic activity.
The three stages of hair growth are the anagen, catagen, and telogen phases. Each strand of hair on the human body is at its own stage of development. Once the cycle is complete, it restarts and a new strand of hair begins to form. The rate or speed of hair growth is about 1.25 centimetres or 0.5 inches per month, or about 15 centimetres or 6 inches per year.
Cortisol is produced in the human body by the adrenal gland in the zona fasciculata, the second of three layers comprising the adrenal cortex. The cortex forms the outer "bark" of each adrenal gland, situated atop the kidneys. The release of cortisol is controlled by the hypothalamus, a part of the brain. The secretion of corticotropin-releasing hormone by the hypothalamus triggers cells in the neighboring anterior pituitary to secrete another hormone, the adrenocorticotropic hormone (ACTH), into the vascular system, through which blood carries it to the adrenal cortex. ACTH stimulates the synthesis of cortisol and other glucocorticoids, mineralocorticoids, and dehydroepiandrosterone.
Scalp hair grows, on average, at a rate of about 1.25 centimeters per month, and shampoos or vitamins have not been shown to noticeably change this rate. Hair growth rate also depends upon what phase in the cycle of hair growth one is actually in; there are three phases. The speed of hair growth varies based upon genetics, gender, age, hormones, and may be reduced by nutrient deficiency (i.e., anorexia, anemia, zinc deficiency) and hormonal fluctuations (i.e., menopause, polycystic ovaries, thyroid disease).
This is the most common cause of anovulation and is thought to account for about 70% of all cases. About half the women with hormonal imbalances do not produce enough follicles to ensure the development of an ovule, possibly due to poor hormonal secretions from the pituitary gland or the hypothalamus. The pituitary gland controls most other hormonal glands in the human body. Therefore, any pituitary malfunctioning affects other glands under its influence, including the ovaries. This occurs in around 10% of cases. The mammary glands are also controlled by the pituitary gland, so lactation can also be affected. The pituitary gland is controlled by the hypothalamus. In 10% of cases, alterations in the chemical signals from the hypothalamus can easily seriously affect the ovaries.
Oxytocin (Oxt) is a peptide hormone and neuropeptide. Oxytocin is normally produced by the paraventricular nucleus of the hypothalamus and released by the posterior pituitary. It plays a role in social bonding, sexual reproduction, childbirth, and the period after childbirth. Oxytocin is released into the bloodstream as a hormone in response to stretching of the cervix and uterus during labor and with stimulation of the nipples from breastfeeding. This helps with birth, bonding with the baby, and milk production. Oxytocin was discovered by Henry Dale in 1906. Its molecular structure was determined in 1952. Oxytocin is also used as a medication to facilitate childbirth.
Auxins were the first of the major plant hormones to be discovered. They derive their name from the Greek word αυξειν ("auxein" – "to grow/increase"). 
Auxin (namely IAA) is present in all parts of a plant, although in very different concentrations. The concentration in each position is crucial developmental information, so it is subject to tight regulation through both metabolism and transport. The result is the auxin creates "patterns" of auxin concentration maxima and minima in the plant body, which in turn guide further development of respective cells, and ultimately of the plant as a whole.
The adrenal glands are located above the kidneys in humans and in front of the kidneys in other animals. The adrenal glands produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. It controls the behaviour during crisis and emotional situations. It stimulates the heart and its conducting tissues and metabolic processes.
The earliest study of endocrinology began in China. The Chinese were isolating sex and pituitary hormones from human urine and using them for medicinal purposes by 200 BCE. They used many complex methods, such as sublimation of steroid hormones. Another method specified by Chinese texts—the earliest dating to 1110—specified the use of saponin (from the beans of "Gleditsia sinensis") to extract hormones, but gypsum (containing calcium sulfate) was also known to have been used.
In the human body at birth, there are over 270 bones, but many of these fuse together during development, leaving a total of 206 separate bones in the adult, not counting numerous small sesamoid bones. The largest bone in the body is the femur or thigh-bone, and the smallest is the stapes in the middle ear.
Xenoestrogens are clinically significant because they can mimic the effects of endogenous estrogen and thus have been implicated in precocious puberty and other disorders of the reproductive system.
Moudgal's early researches at the University of Madras were on the biochemistry of thyroid hormones but he shifted his focus to pituitary gonadotropins during his days at Choh Hao Li's laboratory at the University of California, Berkeley when he established that the hormones generated immune response in living beings and the discovery was reported to be a significant one as the belief till then was the principal function of the hormones was reproduction. Later, at Rodney Porter's laboratory in London, he worked on the role of cellulose as a carrier for immobilization of antibodies. Back in India, he expanded the scope of his researches to cover wider aspects of reproductive biology for which he established a Primate Research Laboratory at IISc in 1965, which was the largest primate house in the country at that time. Working on the macaques in his primate house, he discovered that sialidase from the kidney of the primate acted as an inhibitor of follicle stimulating hormone (FSH), a hormone responsible for pubertal development. He conducted elaborate studies on the molecular mechanism of Luteinizing Hormone (LH), a hormone which has significant role in ovulation and testosterone production, and elucidated the "unfolding of LH binding to LH receptors in the target cell" which was detailed in one of his articles, "Effect of ICSH on Early Pregnancy in Hypophysectomized Pregnant Rats", published in Nature in 1969. He discovered that neutralizing LH resulted in neutralization of several reproductive functions such as ovulation, implantation, and gestational progress and the discovery opened a new methodology in immunocontraceptive technology. Later, he furthered his investigations on hormone actions by using antibodies as probes. His findings reportedly prompted R. O. Greep of Harvard University to invite him for collaborative research and Moudgal supervised the work of Greep's Group at his laboratory. At Harvard, he also collaborated with W. R. Moyle and established the presence of Luteinizing hormone/choriogonadotropin receptors on tumor cells in the testicles for the first time, which they revealed in an article, "Specific binding of luteinizing hormone to Leydig tumor cells", published in the Journal of Biological Chemistry in 1971. He used these tumor cells for further investigations on Hormone-Receptor interactions, Cyclic adenosine monophosphate (cyclic AMP) production and steroidogenesis and experimentally demonstrated the extent of coupling and response with regard to cyclic AMP production and steroid output.
Glutamine is the most abundant naturally occurring, nonessential amino acid in the human body, and one of the few amino acids that can directly cross the blood–brain barrier. Humans obtain glutamine through catabolism of proteins in foods they eat. In states where tissue is being built or repaired, like growth of babies, or healing from wounds or severe illness, glutamine becomes conditionally essential.
The anagen phase is known as the growth phase. This is the phase where the hair physically grows approximately 1 cm per month. It begins in the papilla and can last from two to six years. The span at which the hair remains in this stage of growth is determined by genetics. The longer the hair stays in the anagen phase, the longer it will grow. During this phase, cells neighboring the papilla in a germinative layer divide to produce new hair fibers, and the follicle buries itself into the dermal layer of the skin to nourish the strand. About 85% - 90% of the hairs on one's head are in the anagen phase at any given time.
The Gastrin family is a group of peptides evolutionarily similar in structure and function. Commonly synthesized in antroduodenal G-cells. Regulate gastric function along with gastric acid secretion and mucosal growth.The Secretin family are peptides that act as local hormones which regulate regulate activity of G-protein coupled receptors. Most often found in the pancreas and the intestines. Secretin was discovered in 1902 by E. H. Starling. It was later linked to chemical regulation and was the first substance to be deemed a hormone.
3. Mark H. Whitnall, William G. Haynes, David J. Webb (1997). Principles of Medical Biology.
The adrenal cortex produces three main types of steroid hormones: mineralocorticoids, glucocorticoids, and androgens. Mineralocorticoids (such as aldosterone) produced in the zona glomerulosa help in the regulation of blood pressure and electrolyte balance. The glucocorticoids cortisol and corticosterone are synthesized in the zona fasciculata; their functions include the regulation of metabolism and immune system suppression. The innermost layer of the cortex, the zona reticularis, produces androgens that are converted to fully functional sex hormones in the gonads and other target organs. The production of steroid hormones is called steroidogenesis, and involves a number of reactions and processes that take place in cortical cells. The medulla produces the catecholamines adrenaline and noradrenaline, which function to produce a rapid response throughout the body in stress situations.
A number of endocrine diseases involve dysfunctions of the adrenal gland. Overproduction of cortisol leads to Cushing's syndrome, whereas insufficient production is associated with Addison's disease. Congenital adrenal hyperplasia is a genetic disease produced by dysregulation of endocrine control mechanisms. A variety of tumors can arise from adrenal tissue and are commonly found in medical imaging when searching for other diseases.
The adrenal glands are located on both sides of the body in the retroperitoneum, above and slightly medial to the kidneys. In humans, the right adrenal gland is pyramidal in shape, whereas the left is semilunar or crescent shaped and somewhat larger. The adrenal glands measure approximately 3 cm in width, 5.0 cm in length, and up to 1.0 cm in thickness. Their combined weight in an adult human ranges from 7 to 10 grams. The glands are yellowish in colour.
The ova, which are the female sex cells, are much larger than the sperm and are normally formed within the ovaries of the fetus before its birth. They are mostly fixed in location within the ovary until their transit to the uterus, and contain nutrients for the later zygote and embryo. Over a regular interval, in response to hormonal signals, a process of oogenesis matures one ovum which is released and sent down the Fallopian tube. If not fertilized, this egg is released through menstruation in humans and other great apes, and reabsorbed in other mammals in the estrus cycle.
Secretin was the first hormone to be identified. In 1902, William Bayliss and Ernest Starling were studying how the nervous system controls the process of digestion. It was known that the pancreas secreted digestive juices in response to the passage of food (chyme) through the pyloric sphincter into the duodenum. They discovered (by cutting all the nerves to the pancreas in their experimental animals) that this process was not, in fact, governed by the nervous system. They determined that a substance secreted by the intestinal lining stimulates the pancreas after being transported via the bloodstream. They named this intestinal secretion "secretin". Secretin was the first such "chemical messenger" identified. This type of substance is now called a hormone, a term coined by Bayliss in 1905.
Biological exponential growth is the exponential growth of biological organisms. When the resources availability is unlimited in the habitat, the population of an organism living in the habitat grows in an exponential or geometric fashion. Population growth in which the number of individuals increase by a constant multiple in each generation. The potential for population growth can be demonstrated in the laboratory under conditions that provide abundant resources and space. For example, a few fruit flies in a large culture jar containing an abundant food source may reproduce rapidly. One female fruit fly may lay more than 50 eggs. Reproductive adults develop in about 14 days, with approximately equal numbers of male and female offspring. For each female that began the population, 50 flies are expected 2 weeks later. Each female in the second generation produces 50 more flies after 2 more weeks, and so on. In other words, the population is experiencing exponential growth. Slow exponential growth is when a population grows slowly yet exponential because the population has long live spans. While a rapid exponential growth refers to a population that grows ( and dies ) rapidly because the population has short life spans.
Grumbach made many seminal contributions the understanding of pediatric endocrinology including extensive studies on the development and function of the endocrine and neuroendocrine systems from fetal life through puberty, as well as studies of the hormonal and genetic effects on growth, bone maturation, puberty, sex determination and differentiation (and their disorders) and disease-causing pathology. He was a past president of the Endocrine Society, the American Pediatric Society, the Lawson Wilkins Pediatric Endocrine Society, the Association of Medical School Pediatric Department Chairmen, and honorary president of the International Endocrine Society. From 1956 to 1990 he supervised the training of 82 fellows from 15 countries on five continents. No single individual trained as many leaders or had a broader impact on Pediatric Endocrinology. He died on October 4, 2016 of a heart attack.
The major isoform of the human growth hormone is a protein of 191 amino acids and a molecular weight of 22,124 daltons. The structure includes four helices necessary for functional interaction with the GH receptor. It appears that, in structure, GH is evolutionarily homologous to prolactin and chorionic somatomammotropin. Despite marked structural similarities between growth hormone from different species, only human and Old World monkey growth hormones have significant effects on the human growth hormone receptor.
Human growth hormone is a naturally occurring hormone that is responsible for general body growth in both men and women. hGH helps the body protein while breaking down fat deposits. Too much hGH results in increased muscle mass. (Santella 45)
Growth hormone therapy refers to the use of growth hormone (GH) as a prescription medication—it is one form of hormone therapy. Growth hormone is a peptide hormone secreted by the pituitary gland that stimulates growth and cell reproduction. In the past, growth hormone was extracted from human pituitary glands. Growth hormone is now produced by recombinant DNA technology and is prescribed for a variety of reasons. GH therapy has been a focus of social and ethical controversies for 50 years.
GHRH first appears in the human hypothalamus between 18 and 29 weeks of gestation, which corresponds to the start of production of growth hormone and other somatotropes in fetuses.GHRH is released from neurosecretory nerve terminals of these arcuate neurons, and is carried by the hypothalamo-hypophyseal portal system to the anterior pituitary gland, where it stimulates growth hormone (GH) secretion by stimulating the growth hormone-releasing hormone receptor. GHRH is released in a pulsatile manner, stimulating similar pulsatile release of GH. In addition, GHRH also promotes slow-wave sleep directly. Growth hormone is required for normal postnatal growth, bone growth, regulatory effects on protein, carbohydrate, and lipid metabolism.