text:
[L. cella, a chamber]
In the biological sciences, the basic unit of life. It is a group of self-sustaining biochemical reactions that are isolated from the environment by a selectively permeable lipid membrane. Among the key reactions are those that maintain a stable intracellular concentration of ions. For mammalian cells, typical internal concentrations include 140 mM K+, 5 to 15 mM Na+, 5 to 15 mM Cl-, and a pH of 7.2, which can be significantly different from their concentrations outside the cell. Other key reactions move molecules and molecular complexes within the cell, sometimes changing the shape of the cell. These reactions require energy; energy is generated by breaking apart hydrocarbon molecules by glycolysis and other characteristic intracellular metabolic reactions.
SEE: glycolysis; SEE: metabolism; SEE: mitochondrion
Intracellular chemical reactions are controlled by enzymes that are organized in organelles (stable molecular complexes). The polymer-based organelles include centrioles and the cytoskeleton; nucleic acid-based organelles include ribosomes; and membrane-enclosed organelles include the nucleus, endoplasmic reticula, Golgi complexes, lysosomes, peroxisomes, mitochondria, and storage and transport vesicles.
COMMON COMPONENTS AND ORGANELLES OF HUMAN CELLS Individual mammalian cells are usually microscopic, typically ranging from 5 to 50 µm in diameter. In humans, lymphocytes are small cells (6 µm in diameter), columnar epithelial cells (10 µm x 20 µm) are medium-size cells, and mature ova (120 to 150 µm) are some of the largest cells.
In mammals, all new cells arise from existing cells through cell division, and an animal's growth results largely from increases in the number of its cells, most of which differentiate into specialized cell types to form the body's various tissues. Cell division involves two major processes: karyokinesis, the division of the nucleus, and cytokinesis, the division of the remainder of the cell. When generating somatic daughter cells, karyokinesis uses a process called mitosis, which produces daughter cells with a full complement of chromosomes. When generating germ cells, karyokinesis includes a process called meiosis, which produces daughter cells with half the normal number of chromosomes.
SEE: meiosis and SEE: mitosis for illus
A cell
SEE: Alpha cell.
accessory cell
A monocyte or macrophage that participates in the immune response.
SEE: antigen-presenting cell; SEE: macrophage
acidophilic cell
SEE: acidophil
acinar cell
A cell present in the acinus of an acinous gland, e.g., of the pancreas.
adipose cell
SEE: Adipocyte.
adult stem cell
A precursor cell that can also give rise to identical precursor cells. Daughters of a stem cell can develop into a terminally differentiated cell type, or they can remain a stem cell. Adult stem cells are found in many tissues, such as bone marrow, brain, retina, skin, intestines, liver, testis, and pancreas.
SYN: SEE: somatic stem cell
SEE: embryonic stem cell
adventitial cell
A macrophage along a blood vessel, together with its undifferentiated perivascular cells.
air cell
An air-filled sinus cavity in a bone.
alpha cell
1. An enteroendocrine cell that produces glucagon and is found in the pancreatic islets.
SYN: SEE: A cell
2. An acidophil of the adenohypophysis.
SEE: acidophil (2)
alveolar cell
1. Either of two types of epithelial cells lining the alveoli of the lung. Type I cells are simple, thin squamous epithelial cells. Type II cells, which are smaller and more numerous than Type I cells, secrete pulmonary surfactant.
2. In the mammary glands, the milk-secreting epithelial cells, which are activated during lactation.
amacrine cell
A modified nerve cell in the retina that has dendrites but no axon.
SEE: neuron
ameloblast cell
SEE: ameloblast
amine precursor uptake and decarboxylation cell
ABBR: APUD cell Any of the constituent cells of a diffuse neuroendocrine system, having metabolic pathways that make and utilize serotonin (5-HT). APUD cells include chromaffin cells, enterochromaffin cells, and certain cells found in the parathyroid gland, thyroid gland, pituitary gland, hypothalamus, and placenta.
amphophilic cell
A cell that stains with either acid (eosin) or basic (hematoxylin) stains.
SYN: SEE: amphocyte; SEE: amphophil
anterior horn cell
A somatic motor neuron that has its cell body in the ventral (anterior) horn of the gray matter of the spinal cord. Its axon passes out through a ventral root and innervates skeletal muscle.
antibody-secreting cell
A B lymphocyte that differentiates after stimulation by an antigen and a presenting cell to produce and release large amounts of immunoglobulin.
antigen-presenting cell
ABBR: APC A cell that breaks down antigens and displays their fragments on surface receptors next to major histocompatibility complex molecules. This presentation is necessary for some T lymphocytes that are unable to recognize soluble antigens. Macrophages are the primary APCs, but B cells and dendritic cells also can act as APCs.
SEE: T cell
argentaffin cell
A cell in the epithelium of the stomach, intestines, and appendix that secretes serotonin.
astroglial cell
SEE: Astrocyte.
atypical glandular cell
ABBR: AGCs A cell that is an abnormal finding on a Pap test. These cells are divided into "favor neoplasia" or "not otherwise specified" (NOS). NOS is further subdivided into endocervical or endometrial origin. Atypical endocervical cells are important because of their risk for significant disease.
SYN: SEE: atypical glandular cell of undetermined significance
atypical glandular cell of undetermined significance
ABBR: AGUS SEE: Atypical glandular cell.
B cell
A lymphocyte that synthesizes and secretes antibodies. B cells originate and differentiate in the bone marrow and then populate the spleen, lymph nodes, and other lymphoid tissues. When exposed to an antigen, a B cell divides to form 1) plasma cells, which produce antigen-specific antibodies, and 2) a lesser number of memory B cells, which can quickly differentiate into plasma cells upon a second exposure to the original antigen. Antibody production is a key part of the humoral immune response of adaptive immunity. The humoral immune response is effective against bacteria, viruses, and other pathogens and provides the rationale for vaccination.
SYN: SEE: B lymphocyte
SEE: T cell
band cell
The developing leukocyte at a stage at which the nucleus is not segmented.
basal cell
1. A rounded or cuboidal epithelial stem cell found in the bottom layer of pseudostratified epithelia, such as the epidermis and the lining of the airways of the lung.
2. Either of two types of cell found in the bottom layer of the olfactory epithelium.
SEE: basal cell proper; SEE: globose cell
3. A rounded stem cell found in the taste buds and a progenitor of the specialized taste receptor cells.
basal cell proper
A flattened cell found in the bottom layer of the olfactory epithelium.
SEE: basal cell (2)
basket cell
1. A smooth muscle cell found in some epithelia. It lies between glandular cells and the basal lamina of sweat, mammary, lacrimal, and salivary glands.
SYN: SEE: myoepithelial cell
2. Any of the granule cells found in the cerebral cortex.
3. Any of the small interneurons found in the outermost layer of the cerebellar cortex together with stellate cells.
SEE: stellate cell
basophilic cell
SEE: basophil
beta cell
1. Any of the insulin-secreting cells of the pancreas that constitute the bulk of the islets of Langerhans.
2. A basophil of the adenohypophysis.
Betz cell
SEE: Betz cells
bipolar cell
SEE: bipolar neuron
blast cell
1. A precursor cell for a specific cell type.
2. An immature cell of a specific type.
blood cell
Any cell normally found circulating in the bloodstream. Blood cells include red cells and white cells. Red cells generally remain inside blood vessels; white cells can also move into the tissues outside the blood vessel walls.
SEE: blood for illus
bone cell
An osteoblast, osteoclast, or osteocyte.
SEE: osteoblast; SEE: osteoclast (2); SEE: osteocyte
bone marrow cell
SEE: Myeloid cell.
brush cell
An epithelial cell found sparsely in the lining of the bronchial tree. The surface of the cell has long stiff microvilli.
burr cell
SEE: Echinocyte.
cancer cell
A cell present in a neoplasm and differentiated from normal tissue cells because of its degree of anaplasia, irregularity of shape, nuclear size, changes in the structure of the nucleus and cytoplasm, increased number of mitoses, and ability to metastasize.
capsule cell
SEE: Satellite cell (2).
cartilage cell
SEE: Chondrocyte.
castration cell
An enlarged and vacuolated basophil seen in the pituitary in gonadal insufficiency or following castration.
SEE: basophil
CD3 cell
SEE: helper cell; SEE: T cell
CD4 cell
SEE: helper cell; SEE: T cell
CD8 cell
SEE: cytotoxic T cell; SEE: suppressor T cell
CD 34+ cell
A cell with the CD34 protein on its surface membrane. Some CD34 cells that are hemopoietic stem cells can be separated out from peripheral blood.
cementoblast cell
SEE: cementoblast
cementocyte cell
Any of the cells trapped within cementum whose metabolic activity maintains the cementum as living calcified tissue.
SEE: cementum
centroacinar cell
A duct cell of the pancreas invaginated into the lumen of an acinus.
chemoreceptor cell
SEE: chemoceptor
chief cell
1. Any of the cells of the parathyroid gland that secretes parathyroid hormone.
2. Any of the cells of the gastric glands that secretes pepsinogen.
chromaffin cell
A cell that produces, stores, and secretes catecholamines. The cells are found in the medulla of the adrenal glands and in small clusters in the sympathetic ganglia.
chromophobe cell
SEE: chromophobe
circulating tumor cell
SEE: Micrometastasis.
Clara cell
SEE: Clara cell
cleavage cell
SEE: Blastomere.
clue cell
A vaginal epithelial cell, thickly coated with coccobacillary organisms. The cells are a hallmark of bacterial vaginosis.
columnar cell
An epithelial cell with height greater than its width.
SYN: SEE: columnar epithelial cell
columnar epithelial cell
SEE: Columnar cell.
cone cell
A cell in the retina whose scleral end forms a cone that serves as a light receptor. Vision in bright light, color vision, and acute vision depend on the function of the cones.
SEE: rod cell
contrasuppressor cell
A T cell that inhibits the activity of suppressor T cells. A contrasuppressor cell shares this function with T helper cells, but it is distinguished from other CD4+ cells by its other cell surface markers and its unique group of cytokines.
SEE: helper cell; SEE: T cell
cortical cell
A cell in the cortex of an organ, e.g., a neuron in the cerebral cortex.
cuboid cell
A cell, usually epithelial, with a height approx. equal to its width and depth.
cytotoxic cell
SEE: Cytotoxic T cell
cytotoxic T cell
A CD8+ T lymphocyte that can destroy microorganisms directly through the release of perforin and proteolytic enzymes. These cells are particularly important in the defense against viruses, rejection of allografts, and, possibly, new malignant cells.
SYN: SEE: cytotoxic cell; SEE: killer T cell
D cell
An enteroendocrine cell that produces somatostatin and is found in the pancreatic islets, stomach, and small intestine.
SYN: SEE: delta cell; SEE: somatostatin cell
daughter cell
A cell formed by cell division.
decoy cell
A cell found in the urine with inclusion bodies in its nucleus. It indicates infection in renal transplant recipients.
delta cell
SEE: D cell.
dendritic cell
An antigen-presenting cell that helps T cells respond to foreign antigens. Dendritic cells circulate in the blood and are also found in epithelial tissues, the Langerhans cells of the skin, and the interdigitating cells in lymph nodes.
Downey cell
SEE: Downey cell
dust cell
A macrophage that migrates into the lumen of lung aveoli and ingests debris, particles of air pollution, and pathogens to keep the airspaces clear.
EC cell
1. A cultured cell line of an embryonal carcinoma cell.
2. An enterochromaffin cell that secretes substance P and is found in the stomach and small intestine.
effector cell
A cell that carries out the final response or function of a particular process. The main effector cells of the immune system are activated lymphocytes and phagocytes.
SEE: leukocyte
effector B cell
SEE: Plasma cell
embryonic stem cell
ABBR: ES cell A cell from the inner cell mass of the blastocyst that can give rise to all the somatic cells of the body. Embryonic stem cells can be maintained as pure stem cell cultures.
SEE: adult stem cell
endothelial cell
Any of the epithelial cells that line blood vessels and lymph vessels. These cells are derived from mesenchyme cells of the embryo, are usually squamous, and form sheets one layer thick.
SEE: endothelium
enterochromaffin cell
ABBR: EC cell An enteroendocrine cell that is found in the small intestine and produces serotonin. Enterochromaffin cells are similar to chromaffin cells.
enteroendocrine cell
Any of the scattered hormone-producing cells found in the pancreatic islets and throughout the gastrointestinal mucosa.
ependymal cell
Any of the epithelial cells that form a one-cell-thick layer lining the ventricles and the central canal of the central nervous system. The ventricular (apical) surfaces of many ependymal cells are covered with cilia or microvilli. Specialized regions of ependymal cells include the covering of the blood vessels and loose connective tissue of the choroid plexus.
SYN: SEE: ependymoblast; SEE: ependymocyte
SEE: choroid plexus
epithelial cell
Any of the cells forming the cellular sheets that cover surfaces inside and outside the body. Epithelial cells are closely packed and take on polyhedral shapes, from tall (columnar) through squat (cuboidal) to flat (squamous). Epithelial cells adhere strongly to one another, and one of their surfaces (the basal) sticks firmly to the basal lamina.
SEE: epithelium
ethmoid cell
SEE: Ethmoid sinus.
ethmoid air cell
SEE: Ethmoid sinus.
eukaryotic cell
The type of cell composing multicellular and a number of unicellular organisms. Unlike prokaryotic cells, eukaryotic cells have many of their intracellular functions organized within organelles.
SEE: organelle
F cell
An enteroendocrine cell that produces pancreatic polypeptide and is found in the pancreatic islets.
fat cell
SEE: Adipocyte.
flame cell
A bone marrow cell with a bright red cytoplasm, occasionally found in the marrow of patients with multiple myeloma.
flow cell
An optical cell used in photometers and cell counters. Samples and standards are passed for detection and measured or counted by optical or electrometric means.
SEE: cytometry
flower cell
Abnormal lymphocytes with petal-shaped nuclei.
foam cell
A lipid-filled macrophage that contains vacuoles.
follicle cell
SEE: Follicular cell.
follicular cell
1. The secretory cell of the thyroid gland.
SEE: thyroid hormone
2. Any of the flattened somatic cells that form a monolayer around each primary oocyte in the ovary. After puberty, when an oocyte matures, during a monthly cycle, its follicular cells divide, become cuboidal, and form a multilayered coating for the oocyte; at this stage, the follicular cells are called granulosa cells.
SYN: SEE: follicle cell
folliculostellate cell
A supporting cell in the adenohypophysis. It produces bioactive peptides, including growth factors and cytokines.
foreign body giant cell
SEE: Giant cell.
G cell
An enteroendocrine cell that is found in the stomach and produces gastrin.
ganglion cell
1. Any neuron whose cell body is located within a ganglion.
2. A neuron of the retina of the eye whose cell body lies in the ganglion cell layer. The axons of ganglion cells form the optic nerve.
germ cell
A cell whose function is to reproduce the organism. Early in development, primordial germ cells are found in the genital ridges of the embryo. Later, in the testis, the primordial germ cells are called spermatogonia, and in the ovary, they are called oogonia. When they mature, the germ cells, i.e., spermatogonia and oogonia, differentiate into haploid gametes, i.e., spermatozoa and ova.
giant cell
1. A multinucleated phagocyte created by several individual macrophages that have merged around a large pathogen or a substance resistant to destruction, such as a splinter or surgical suture.
SEE: granuloma; SEE: tuberculosis
2. A large multinucleated (40 to 60 nuclei) tumor cell characteristic of certain bone and tendon tumors.
3. A large multinucleated cell that invades the walls of the aorta and its major branches in giant cell arteritis.
SYN: SEE: foreign body giant cell; SEE: multinucleated giant cell; SEE: syncytial giant cell
gitter cell
A macrophage present at sites of brain injury. The cells are packed with lipoid granules from phagocytosis of damaged brain cells.
SEE: microglia
glial cell
glia cell One of three types of cells in the central nervous system that are not neuronal.
SYN: SEE: neuroglial cell; SEE: neurogliacyte
SEE: astrocyte; SEE: microglial cell; SEE: oligodendrocyte
globose cell
One of two types of basal cell found in the olfactory epithelium. It is a rounded neuroblast or neural stem cell for the olfactory receptor cells.
goblet cell
A mucous cell located between nonsecretory cells, as is found in the intestinal epithelium.
Golgi cell
SEE: Golgi, Camillo
graft facilitating cell
Any of a group of CD8+ T-cell receptor-negative cells that help donated bone marrow engraft in the recipient.
granule cell
1. Any of the small neurons that pack the granular cell layer of the cerebellar cortex, immediately below the Purkinje cell layer. Granule cells receive inputs from the spinal cord and brainstem. Axons of granule cells run perpendicular to the Purkinje cell dendrites, on which they synapse.
2. Any of the neurons of the cerebral cortex that are not pyramidal cells. Cortical granule cells are categorized as spiny or nonspiny.
3. A small neuron that has no axons, found in the olfactory bulb.
granulosa cell
One of the many cuboidal cells that surround and nurture the maturing oocyte.
SEE: follicular cell
gustatory cell
SEE: Taste cell.
hair cell
An epithelial cell possessing stereocilia in the maculae, cristae ampullaris, and organ of Corti. These cells are receptors for the senses of position and hearing. Hair cells do not regenerate after they are damaged or lost.
heart failure cell
A red lung macrophage often found in the sputum of patients with congestive heart failure. The red color is due to ingested red cells.
HeLa cell
A line of human epithelial cells that grows well in culture. It is an immortal cancer cell that has been maintained in continuous tissue cultures for decades from a patient with carcinoma of the cervix. It is named for the first two letters of the patient's first and last names, Henrietta Lacks. HeLa cells have been used in thousands of experiments on cell growth, differentiation, and cancer, and in virology, pharmacology, and other fields.
helmet cell
A schistocyte or fragmented blood cell, seen in hemolytic anemias.
HELMET CELLS (Orig. mag. ×640)
helper cell
A type of T lymphocyte whose surface is marked by CD4 receptors; it is involved in both cell-mediated and antibody-mediated immune responses. It secretes cytokines that stimulate the activity of B cells and other T cells and binds with class II histocompatibility antigens, which are processed by macrophages and other antigen-presenting cells.
SYN: SEE: helper T cell
SEE: antigen processing; SEE: T cell; SEE: cell-mediated immunity
helper T cell
SEE: Helper cell
hematopoietic stem cell
A progenitor cell in the bone marrow that can replicate itself and produce precursor cells of the various blood cell lineages.
hilus cell
An androgen-producing cell found in the ovarian hilum and analogous to a Leydig cell.
SEE: Leydig cell
holly leaf cell
A cell found in blood smears of people with sickle cell anemia.
horizontal cell
A neuron of the inner nuclear layer of the retina. The axons of these cells run horizontally and connect various parts of the retina.
Hürthle cell
SEE: Hürthle cell
hybridoma cell
SEE: hybridoma
hyperchromatic cell
A cell that contains more than the normal number of chromosomes and hence stains more densely.
I cell
An enteroendocrine cell that is found in the small intestine and produces cholecystokinin.
IgE-effector cell
Any of the white blood cells, including basophils and eosinophils, released during allergic reactions.
interdigitating cell
A type of antigen-presenting cell found in lymph nodes and lymphoid tissue.
interstitial cell
Any of the numerous cells found in connective tissue of the ovary, in the seminiferous tubules of the testes, and in the medulla and cortex of the kidney. The cells in the testes and ovaries produce hormones such as testosterone and estrogen.
interstitial cell of Cajal
Any of the nerve cells in the gastrointestinal tract that form pacemaking networks that allow normal peristalsis to occur. Diseases affecting the number or the functioning of these cells cause gastrointestinal motility disorders.
intestinal absorptive cell
In the small intestine, any of the tall columnar cells topped with a brush border made of microvilli.
islet cell
A cell of the islets of Langerhans of the pancreas.
juvenile cell
The early developmental form of a leukocyte.
juxtaglomerular cell
A modified smooth muscle cell in the wall of the afferent arteriole leading to a glomerulus of the kidney. This cell secretes renin when blood pressure decreases to activate the renin-angiotensin mechanism, which increases sodium retention, thus elevating the blood pressure.
K cell
An enteroendocrine cell that is found in the small intestine and produces glucose-dependent insulinotropic peptide.
killer cell
SEE: Natural killer cell
killer T cell
SEE: Cytotoxic T cell.
Kulchitsky cell
An APUD cell found in the lung.
Kupffer cell
SEE: Kupffer cell
L cell
An enteroendocrine cell that is found in the small intestine and produces glucagon-like peptide-1.
labile cell
A cell that is always mitotically active, such as the epithelial cells lining the stomach and the stem cells in the red bone marrow.
lactotroph cell
SEE: lactotroph
Langerhans cell
SEE: Langerhans cell under SEE: Langerhans, Paul
LE cell
An abbreviation for lupus erythematosus (LE) cell, a polymorphonuclear leukocyte that contains the phagocytized nucleus of another cell. This cell may form when the blood of patients with systemic lupus erythematosus (SLE) is incubated and further processed according to protocol. The plasma of some patients contains an antibody to the nucleoprotein of leukocytes. These altered nuclei, which are swollen, pink, and homogeneous, are ingested by phagocytes, which are the LE cells. The ingested material, when stained properly, is lavender and displaces the nucleus of the phagocyte to the inner surface of the cell membrane. The LE cell phenomenon can be demonstrated in most patients with SLE but is not essential for diagnosis.
LE CELL (center) (Orig. mag. ×1000)
Leydig cell
SEE: Leydig cell
littoral cell
A macrophage found in the sinuses of lymphatic tissue.
liver cell
Any of the cells that make up 70% to 85% of the liver's cytoplasmic mass. These cells are involved in synthesis and storage of protein; the transformation of carbohydrates; the synthesis of cholesterol, bile salts and phospholipids; and the detoxification, modification, and excretion of exogenous and endogenous substances. They also initiate the formation and secretion of bile.
lutein cell
A cell of the corpus luteum of the ovary that contains fatty yellowish granules. Granulose lutein cells are hypertrophied follicle cells that develop from the theca interna.
lymphoid cell
SEE: Lymphocyte.
lymphokine-activated killer cell
ABBR: LAK cell Any of the natural killer cells obtained from the patient's blood and activated in culture with interleukin-2 LAK cells. The cells can then be used to treat patients with solid malignant tumors.
macroglial cell
An astrocyte or an oligodendrocyte.
SEE: astrocyte; SEE: oligodendrocyte
marrow cell
SEE: Myeloid cell.
mast cell
A large tissue cell resembling a basophil, essential for allergic and inflammatory reactions mediated by immunoglobulin E (IgE). Mast cells do not circulate in the blood although the substances they release may have systemic effects. Mast cells are present throughout the body in connective tissue, but are concentrated beneath the skin and the mucous membranes of the respiratory and digestive tracts. Mast cells are covered with IgE molecules, which bind with foreign antigens and stimulate degranulation, releasing such mediators as histamine, prostaglandins, leukotrienes, and proteinases from densely packed granules within the cytoplasm. These mediators produce type I (immediate) hypersensitivity reactions, e.g., urticaria, allergic rhinitis, asthma, angioedema, and systemic anaphylaxis.
mastoid cell
SEE: Mastoid air cell
mastoid air cell
Any of the variable-sized, air-filled sinuses inside the mastoid process. About 20% of adult skulls have no mastoid air cells.
SYN: SEE: mastoid cell
matrix stem cell
A stem cell derived from Wharton jelly.
memory cell
A cell derived from B or T lymphocytes that can quickly recognize a foreign antigen to which the body has been previously exposed. Memory T cells stimulate T helper lymphocytes and cytotoxic T cells; memory B cells stimulate the production of antigen-specific antibodies by B plasma cells. Both types of memory cells survive for years, providing a durable adaptive immune response against foreign antigens.
mesectodermal cell
SEE: Neural crest cell
mesenchyme cell
One of the two basic somatic cell lineages. The second somatic cell lineage is the epithelial. In contrast to epithelial cells, mesenchyme cells are not polarized and are frequently motile. In the early embryo, mesenchyme cells fill many of the spaces enclosed by epithelia. Later, mesenchyme cells will secrete the space-filling extracellular matrix molecules, such as collagen and glycoproteins, that characterize connective tissue.
mesenchymal stem cell
A stem cell found in connective tissue and capable of producing cells of the connective tissue lineages, such as cartilage, bone, muscle, and fat cells.
mesothelial cell
The type of epithelial cell that lines serous (pleural, peritoneal, and pericardial) cavities, blood vessels, and lymph vessels. These cells are usually squamous and form sheets (mesothelia) one layer thick. They are derived from mesenchyme cells of the embryo.
SEE: mesothelium
microfold cell
ABBR: M cell
1. A cell in the gastrointestinal epithelium, covering patches of lymphoid tissue. M cells transport antigens from the intestinal lumen to the underlying lymphoid tissues for recognition and processing.
2. An APUD cell that produces melanotropin and is found in the pituitary gland.
microglial cell
A small glial cell of the central nervous system and retina. Microglia have spiky branched processes and are arranged homogeneously throughout the brain and spinal cord. They are activated by disease and injury, after which they become phagocytic and sometimes resume their embryonic motility, like a macrophage.
mitral cell
One of the two principal neurons of the olfactory bulb. The other principal neuron of the olfactory bulb is the tufted cell. In a glomerulus, the mitral and tufted cells receive synaptic inputs from axons of the olfactory nerve. The axons of the mitral and tufted cells form the olfactory tract and synapse in the olfactory cortex.
mossy cell
An astrocyte or other glial cell with many branching processes.
SEE: glial cell; SEE: neuroglia
mother cell
A cell that gives rise to similar cells through fission or budding.
SYN: SEE: parent cell
mucosal cell
Any cell in a mucosal epithelium.
mucous cell
An epithelial cell that secretes mucus and IgA antibodies. Mucous cells and serous cells are the two varieties of secretory cells found in exocrine glands.
multinucleated giant cell
SEE: Giant cell
multipolar cell
SEE: Multipolar neuron.
multi-potential progenitor cell
SEE: Stem cell.
muscle cell
SEE: muscle
myeloid cell
Any white blood cell other than lymphocytes.
SYN: SEE: bone marrow cell
myeloma cell
A cell present in the bone marrow of patients with multiple myeloma.
myoepithelial cell
SEE: Basket cell (1).
natural killer cell
ABBR: NK cell A large granular lymphocyte that bonds to cells and lyses them by releasing cytotoxins. NK cells are null cells and cannot be activated without previous antigen exposure. NK cells destroy cells infected with viruses and some types of tumor cells in cultures. They also secrete gamma interferon, tumor necrosis factor alpha, and granulocyte-macrophage colony-stimulating factor, which enhance the effect of T lymphocytes.
SYN: SEE: killer cell
nerve cell
SEE: Neuron.
neural crest cell
Any of the embryonic cells of the neuron-glia lineage that form along the neural folds and migrate into the developing organism to produce a variety of tissues. The migratory ability of these embryonic epithelial cells is similar to the motility of mesenchyme cells and has led neural crest cells to be called mesectodermal cells. In the neural lineage, neural crest cells give rise to the dorsal root ganglia, the placodes that will develop into the olfactory and auditory sensory organs, the pituitary gland, the peripheral autonomic nervous system, and the neurenteric and APUD cells. In the glial lineage, neural crest cells give rise to Schwann cells and other peripheral satellite cells. In addition, neural crest cells of the cranial region give rise to certain facial connective tissue, including the bones of the nasal cavities, the roof of the mouth, and the sella turcica.
SYN: SEE: mesectodermal cell
neuroglial cell
SEE: Glial cell.
Niemann-Pick cell
SEE: Niemann-Pick cell
nonstem cell
Any cell found in the bone marrow that cannot reconstitute the marrow or give rise to more differentiated blood cells.
null cell
1. A large lymphocyte without the cell markers of either a T cell or a B cell. Natural killer cells are examples of null cells.
2. A cell within a pituitary adenoma that neither produces nor secretes hormones.
nurse cell
A cell that binds to an oocyte and stimulates its development by supplying it with messenger RNA, ribosomes, and proteins.
odontoblast cell
SEE: odontoblast
oligodendroglial cell
SEE: oligodendrocyte.
olfactory cell
olfactory receptor cell
A cell of the olfactory mucosa that has receptors for the sense of smell. Olfactory cells are continuously replaced from stem cells throughout adult life.
SYN: SEE: olfactory cell
osteoprogenitor cell
Any of the mesenchyme precursor cells capable of producing osteoblasts and osteocytes. Osteoprogenitor cells are found in bone, bone marrow, and other connective tissue.
oxyntic cell
SEE: Parietal cell
parabasal cell
Small, ovoid, or round epithelial cells seen on cytological examination of vaginal smears. They have relatively large nuclei relative to their proportion of cytoplasm.
parent cell
SEE: Mother cell.
parietal cell
A large cell on the margin of the gastric glands of the stomach that secretes hydrochloric acid and intrinsic factor.
SYN: SEE: oxyntic cell
SEE: achlorhydria; SEE: anemia, pernicious; SEE: intrinsic factor
phalangeal cell
One of the cells supporting the hair cells of the organ of Corti. These cells form several rows of Deiters cells (outer phalangeal cells) and a single row of inner phalangeal cells.
SEE: Deiters cell (under Deiters, Otto F.C.)
phantom cell
SEE: red cell ghost
pigment cell
Any cell that normally contains pigment granules.
pillar cell
One of two groups of cells (inner and outer) resting on the basement membrane of the organ of Corti in which elongated bodies (pillars) develop. These enclose the inner tunnel (Corti tunnel).
plasma cell
A cell derived from a B lymphocyte that has been sensitized to a specific foreign antigen and produces antibodies to that particular antigen. It may be found in the blood or in tissue fluid.
SYN: SEE: effector B cell
plasmacytoid dendritic cell
ABBR: pDC Any of a subset of dendritic cells that, after contact with malignant cells or pathogens, migrate to lymph nodes and lymphoid organs, secrete interferons and other regulatory cytokines, and stimulate cellular immune responses by T lymphocytes. Overactivation of pDCs is commonly identified in autoimmune diseases like systemic lupus erythematosus and systemic sclerosis.
postganglionic cell
PP cell
An enteroendocrine cell that is found in the pancreatic islets and produces pancreatic polypeptide.
pre-B cell
The immediate precursor of a lymphocytic B cell.
precursor cell
SEE: Stem cell.
preganglionic cell
prickle cell
A cell with spiny processes that connect with similar processes of adjoining cells. These are found in the stratum spinosum of the keratinized epithelium of the epidermis.
primary cell
In physical therapy, a device consisting of a container, two solid conducting elements, and an electrolyte for the production of electric current by chemical energy.
primordial cell
SEE: germ cell
primordial germ cell
SEE: germ cell
progenitor cell
SEE: A cell (sometimes a stem cell) that produces cells of a particular lineage, e.g., a neuroblast.
prokaryotic cell
A cell composing many primitive unicellular organisms, such as bacteria. Prokaryotic cells do not have nuclei, which are partitioned by an intracellular membrane; instead the DNA forms one main coil in the cell cytoplasm.
Purkinje cell
pus cell
A leukocyte present in pus. Pus cells are often degenerated or necrotic.
pyramidal cell
A large common neuron found in the cerebral cortex. Pyramidal cells are flask-shaped or triangular and, in the parts of the cortex with six layers, occupy the fifth layer. Pyramidal cell dendrites project up into the most superficial layer of the cortex, while pyramidal cell axons run in the opposite direction, i.e., downward and out of the cortex.
radial glial cell
A structural macroglial cell that is a key component of the developing nervous system. Radial glial cells first appear in the neural tube, where their cell bodies are suspended between two thin cell processes. The apical process attaches to the inner (ventricular) surface of the neural tube, and the basal process attaches to the outer (pial) surface. Early in development, neuroblasts migrate radially along the scaffolding formed by the radial glial cell processes, and growing axons may follow the scaffolding longitudinally. Later, many radial glial cells retract their processes and differentiate into astrocytes.
red cell
SEE: Erythrocyte.
red blood cell
ABBR: RBC SEE: Erythrocyte.
regulatory B cell
ABBR: Breg A B lymphocyte that releases interleukin-10 and/or transforming growth factor-beta, and thereby lowers inflammation.
Renshaw cell
SEE: Renshaw cell
resting cell
1. A cell that is not dividing.
SEE: interphase
2. A cell not performing its normal function, e.g., a nerve cell that is not conducting an impulse or a muscle cell that is not contracting.
reticular cell
1. An undifferentiated cell of the spleen, bone marrow, or lymphatic tissue that can develop into one of several types of connective tissue cells or into a macrophage.
2. A cell of reticular connective tissue.
SEE: reticular tissue
reticuloendothelial cell
A cell of the mononuclear phagocyte system.
SEE: mononuclear phagocyte system
Rieder cell
SEE: Rieder cell
rod cell
A cell in the retina of the eye whose scleral end is long and narrow, forming a rod-shaped sensory receptor. Rods are stimulated by light and are essential for vision in dim light.
SEE: cone cell
rosehip cell
An inhibitory neuron in the central nervous system. It synapses with pyramidal cells in the cerebral cortex.
SYN: SEE: rosehip neuron
rosette cell
A rose-shaped cluster of phagocytes surrounding lysed nuclear material or red blood cells. Rosette cells occur frequently in blood in which lupus erythematosus (LE) cells are present. Rosette cells are not diagnostic of LE.
SEE: LE cell
Rouget cell
SEE: Rouget cell
S cell
An enteroendocrine cell that is found in the small intestine and produces secretin.
satellite cell
1. A stem cell associated with skeletal muscle that may form a limited number of new muscle cells after injury.
2. One of the neuroglia cells enclosing the cell bodies of sensory neurons in spinal ganglia.
SYN: SEE: amphicyte; SEE: capsule cell
scavenger cell
A phagocyte that cleans up disintegrating tissues or cells.
Schwann cell
SEE: Schwann cell, under Schwann, Theodore
segmented cell
A segmented neutrophil, i.e., one with a nucleus of two or more lobes connected by slender filaments.
selenoid cell
SEE: red cell ghost
sensory cell
A cell that when stimulated gives rise to nerve impulses that are conveyed to the central nervous system.
septal cell
A type II alveolar cell that is adjacent to a septum of the alveoli and secretes pulmonary surfactant.
serous cell
An epithelial cell that secretes a watery fluid containing proteins, glycoproteins, and often antibodies (IgA, IgG, and IgM). Serous cells and mucous cells are the two varieties of secretory cells found in exocrine glands.
Sertoli cell
SEE: Sertoli cell
sex cell
SEE: Gamete.
sickle cell
An abnormal erythrocyte shaped like a sickle.
SYN: SEE: drepanocyte
SEE: sickle cell anemia
signet-ring cell
A vacuolated cell with an off-center nucleus. Mucus-secreting adenocarcinomas usually contain these cells.
skeletal muscle cell
SEE: muscle
smooth muscle cell
SEE: muscle
somatic cell
Any cell that is not a germ cell.
somatic stem cell
SEE: Adult stem cell.
somatostatin cell
SEE: D cell.
spiculed red cell
Crenated red blood cells with surface projections. This is usually a normal variation in red cell equilibrium and is reversible.
SEE: acanthocyte
spider cell
SEE: Astrocyte.
squamous cell
A flat epithelial cell.
SYN: SEE: squamous epithelial cell
squamous epithelial cell
SEE: Squamous cell.
stellate cell
1. A granule cell of the cerebral cortex.
2. Any of the small interneurons found in the outer layer of the cerebellar cortex along with basket cells.
SEE: basket cell (3)
stellate reticuloendothelial cell
A Kupffer cell, one of the macrophages that line the sinusoids of the liver.
stem cell
An embryonic stem cell or an adult stem cell.
Sternberg-Reed cell
SEE: Reed-Sternberg cell
stipple cell
A red blood cell that contains small basophilic-staining dots. It is seen in lead poisoning, malaria, severe anemia, and leukemia.
striated muscle
SEE: muscle
suppressor T cell
A subpopulation of regulatory T lymphocytes that develop in the thymus gland and slow or stop a specific immune response. Also known as "regulatory T cell."
sustentacular cell
A supporting cell, as in the acoustic macula, organ of Corti, olfactory epithelium, taste buds, or testes.
sympathicotrophic cell
One of the large epithelial cells that occur in groups in the hilus of the ovary. They are thought to be chromaffin cells.
sympathochromaffin cell
A chromaffin cell of ectodermal origin present in the fetal adrenal gland. Sympathetic and medullary cells originate from these cells.
syncytial giant cell
SEE: Giant cell
T cell
A lymphocyte that responds to specific antigens, with the assistance of antigen-presenting cells (APCs). T cells arise in the bone marrow and migrate to the thymus gland, where they mature; then they circulate between blood and lymph, serving as one of the primary cells of the adaptive immune response. Immature T cells are called thymocytes. Mature T cells are antigen specific. Their surface receptors (T cell receptors) respond only to a single antigen. T cells are further categorized using another family of surface protein markers called clusters of differentiation (CDs). All T cells have a CD3 marker. Additional markers differentiate the subclasses of T cells. CD4 T helper cells serve primarily as regulators, secreting cytokines that stimulate the activities of other white blood cells. CD8 T cells (cytotoxic T cells) directly lyse (kill) organisms, an important defense against viruses; most CD8 T cells also produce gamma interferon (INFγ), one of the strongest stimulators of macrophage activity.
SYN: SEE: T lymphocyte
SEE: immune response; SEE: lymphocyte; SEE: immunological surveillance; SEE: T-cell receptor; SEE: thymocyte
A T cell can only recognize the "foreignness" of antigens after they have been modified by macrophages and other APCs. After this, T cells dominate the adaptive immune response by mobilizing B cells and other T cells of the cell-mediated immune pathways. T cells are responsible for type IV hypersensitivity reactions, such as graft rejection, and for tumor cell recognition and destruction.
SEE: cytokine; SEE: cell-mediated immunity
target cell
1. An erythrocyte with a dark rounded central area surrounded by a lightly stained clear ring, which in turn is surrounded by a dense ring of peripheral cytoplasm. It is present in certain blood disorders, such as thalassemia, and in patients who have no spleen.
SEE: hemoglobin C disease for illus
SYN: SEE: codocyte; SEE: leptocyte
2. The cell at which a signal, e.g., hormone or nerve impulse, is aimed.
TARGET CELLS In hemoglobin C disease (×600)
tart cell
A phagocyte that has ingested the unaltered nuclei of cells. These nuclei can be observed unchanged within the phagocytes.
taste cell
Any of the neuroepithelial cells within a taste bud that are receptors for the sense of taste. Each cell possesses on the free surface a short gustatory hair that projects through the inner taste pore.
SYN: SEE: gustatory cell; SEE: taste receptor cell
taste receptor cell
SEE: Taste cell.
tear-drop cell
An abnormally shaped blood cell, sometimes found on blood smears of patients with bone marrow fibrosis, iron deficiency, or thalassemias.
SYN: SEE: dacrocyte
tendon cell
SEE: Tenocyte.
terminally differentiated cell
A cell sufficiently committed to a particular function that it can no longer divide.
thymic epithelial cell
The epithelial cells that form the internal scaffolding of the thymus. These cells vary in shape and size but generally align in sheets and cords, partitioning the thymus into islands of close-packed lymphocytes in the organ's cortex. Thymic epithelial cells are not simply structural: they interact actively with adjacent lymphocytes.
thymus cell
Any cell characteristic of the thymus, including thymic epithelial cells and thymocytes.
SEE: thymic epithelial cell; SEE: thymocyte
thyroid cell
Any cell characteristic of the thyroid gland, but usually referring to a thyroid follicular cell.
totipotent cell
An undifferentiated embryonic cell that has the potential to develop into any type of cell.
Touton giant cell
SEE: Touton cell
transitional cell
The stretchable epithelial cells that compose the transitional epithelium, which lines most of the urinary tract. Transitional cells are strongly interconnected. They are cuboidal when not under pressure, and they become flattened and squamous when stretched. Transitional epithelia are four to six cells thick, and the top transitional cells on the lumenal surface fuse to become larger and polyploid.
trophoblast cell
Any of the epithelial cells forming the surface of the spherical blastocyst stage embryo. Trophoblast cells are destined to give rise to many of the extraembryonic tissues.
tufted cell
SEE: Mitral cell.
Türk irritation cell
SEE: Türk irritation cell
Tzanck cell
SEE: Tzanck cell
undifferentiated cell
A cell resembling an embryonic cell in that it does not have the specific morphologic or functional characteristics of any particular adult cell type.
unipolar cell
A cell with a single cell process.
Vero cell
A lineage of cells isolated from kidney epithelial cells of the African green monkey (Cercopithecus aethiops) and used in cell cultures.
visual cell
A rod cell or cone cell of the retina.
SEE: cone cell; SEE: rod cell
wandering cell
A rarely used term for a cell (such as a macrophage) that moves like an ameba.
white cell
SEE: Leukocyte.
white blood cell
ABBR: WBC SEE: Leukocyte.


text:
Privacy Notice For California Residents
Owner (or We)
Indicates the natural person(s) or legal entity that provides this Website to Users.
User (or You)
Indicates any natural person or legal entity using this Website.
This Privacy Notice for California Residents supplements the information contained in the Website's Privacy Policy and applies solely to all visitors, users, and others who reside in the State of California. We adopted this notice to comply with the California Consumer Privacy Act of 2018 (CCPA) and any terms defined in the CCPA have the same meaning when used in this notice.
Information We Collect
The Website collects information that identifies, relates to, describes, references, is capable of being associated with, or could reasonably be linked, directly or indirectly, with a particular consumer or device ("personal information").
In particular, Website has collected the following categories of personal information from its consumers within the last 12 months:
Category | Examples | Collected |
A. Identifiers. | A real name, alias, postal address, unique personal identifier, online identifier, Internet Protocol address, email address, account name, Social Security number, driver's license number, passport number, or other similar identifiers. | YES |
B. Personal information categories listed in the California Customer Records statute (Cal. Civ. Code § 1798.80(e)). | A name, signature, Social Security number, physical characteristics or description, address, telephone number, passport number, driver's license or state identification card number, insurance policy number, education, employment, employment history, bank account number, credit card number, debit card number, or any other financial information, medical information, or health insurance information. | YES |
C. Protected classification characteristics under California or federal law. | Age (40 years or older), race, color, ancestry, national origin, citizenship, religion or creed, marital status, medical condition, physical or mental disability, sex (including gender, gender identity, gender expression, pregnancy or childbirth and related medical conditions), sexual orientation, veteran or military status, genetic information (including familial genetic information). | YES |
D. Commercial information. | Records of personal property, products or services purchased, obtained, or considered, or other purchasing or consuming histories or tendencies. | YES |
E. Biometric information. | Genetic, physiological, behavioral, and biological characteristics, or activity patterns used to extract a template or other identifier or identifying information, such as fingerprints, faceprints, and voiceprints, iris or retina scans, keystroke, gait, or other physical patterns, and sleep, health, or exercise data. | YES |
F. Internet or other similar network activity. | Browsing history, search history, information on a consumer's interaction with a Website, application, or advertisement. | YES |
G. Geolocation data. | Physical location or movements. | YES |
H. Sensory data. | Audio, electronic, visual, thermal, olfactory, or similar information. | YES |
I. Professional or employment-related information. | Current or past job history or performance evaluations. | YES |
J. Non-public education information (per the Family Educational Rights and Privacy Act (20 U.S.C. Section 1232g, 34 C.F.R. Part 99)). | Education records directly related to a student maintained by an educational institution or party acting on its behalf, such as grades, transcripts, class lists, student schedules, student identification codes, student financial information, or student disciplinary records. | YES |
K. Inferences drawn from other personal information. | Profile reflecting a person's preferences, characteristics, psychological trends, predispositions, behavior, attitudes, intelligence, abilities, and aptitudes. | YES |
Personal information does not include:
- Publicly available information from government records.
- Deidentified or aggregated consumer information.
- Information excluded from the CCPA's scope, like certain health or medical information and other categories of information protected by different laws.
We obtain the categories of personal information listed above from the following categories of sources:
- Directly from you. For example, from forms you complete or products and services you purchase.
- Indirectly from you. For example, from observing your actions on our Website.
Use of Personal Information
We may use or disclose the personal information we collect for one or more of the following business purposes:
- To fulfill or meet the reason you provided the information. For example, if you share your name and contact information to request a price quote or ask a question about our services, we will use that personal information to respond to your inquiry. If you provide your personal information to purchase a product or service, we will use that information to process your payment and facilitate delivery. We may also save your information to facilitate new product orders or process returns.
- To process your requests, purchases, transactions, and payments and prevent transactional fraud.
- To provide you with support and to respond to your inquiries, including to investigate and address your concerns and monitor and improve our responses.
- To respond to law enforcement requests and as required by applicable law, court order, or governmental regulations.
- As described to you when collecting your personal information or as otherwise set forth in the CCPA.
- To evaluate or conduct a merger, divestiture, restructuring, reorganization, dissolution, or other sale or transfer of some or all of our or our affiliates' assets in which personal information held by us or our affiliates about our Website users is among the assets transferred.
We will not collect additional categories of personal information or use the personal information we collect for materially different, unrelated, or incompatible purposes without providing you notice.
Sharing Personal Information
We may disclose your personal information to a third party for a business purpose. When we disclose personal information for a business purpose, we enter a contract that describes the purpose and requires the recipient to both keep that personal information confidential and not use it for any purpose except performing the contract.
We share your personal information with the following categories of third parties:
- Service providers.
- Data Aggregators.
Your Rights and Choices
The CCPA provides consumers (California residents) with specific rights regarding their personal information. This section describes your CCPA rights and explains how to exercise those rights.
Access to Specific Information and Data Portability Rights
You have the right to request that we disclose certain information to you about our collection and use of your personal information over the past 12 months. Once we receive and confirm your verifiable consumer request (see Exercising Access, Data Portability, and Deletion Rights), we will disclose to you:
- The categories of personal information we've collected about you.
- The categories of sources for the personal information we've collected about you.
- Our business or commercial purpose for collecting or selling that personal information.
- The categories of third parties with whom we share that personal information.
- The specific pieces of personal information we've collected about you (also called a data portability request).
- If we sold or disclosed your personal information for a business purpose, two separate lists disclosing:
- sales, identifying the personal information categories that each category of recipient purchased; and
- disclosures for a business purpose, identifying the personal information categories that each category of recipient obtained.
Deletion Request Rights
You have the right to request that we delete any of your personal information that we collected from you and retained, subject to certain exceptions. Once we receive and confirm your verifiable consumer request (see Exercising Access, Data Portability, and Deletion Rights), we will delete (and direct our service providers to delete) your personal information from our records, unless an exception applies.
We may deny your deletion request if retaining the information is necessary for us or our service provider(s) to:
- Complete the transaction for which we collected the personal information, provide a good or service that you requested, take actions reasonably anticipated within the context of our ongoing business relationship with you, or otherwise perform our contract with you.
- Detect security incidents, protect against malicious, deceptive, fraudulent, or illegal activity, or prosecute those responsible for such activities.
- Debug products to identify and repair errors that impair existing intended functionality.
- Comply with the California Electronic Communications Privacy Act (Cal. Penal Code § 1546 seq.). Enable solely internal uses that are reasonably aligned with consumer expectations based on your relationship with us.
- Comply with a legal obligation.
- Make other internal and lawful uses of that information that are compatible with the context in which you provided it.
Exercising Access, Data Portability, and Deletion Rights
To exercise the access, data portability, and deletion rights described above, please submit a verifiable consumer request to us by either:
- Calling us at
- Emailing us at
Only you, or a person registered with the California Secretary of State that you authorize to act on your behalf, may make a verifiable consumer request related to your personal information. You may also make a verifiable consumer request on behalf of your minor child.
You may only make a verifiable consumer request for access or data portability twice within a 12-month period. The verifiable consumer request must:
- Provide sufficient information that allows us to reasonably verify you are the person about whom we've collected personal information or an authorized representative.
- Describe your request with sufficient detail that allows us to properly understand, evaluate, and respond to it.
We cannot respond to your request or provide you with personal information if we cannot verify your identity or authority to make the request and confirm the personal information relates to you.
Making a verifiable consumer request does not require you to create an account with us.
We will only use personal information provided in a verifiable consumer request to verify the requestor's identity or authority to make the request.
Response Timing and Format
We endeavor to respond to a verifiable consumer request within forty-five (45) days of its receipt. If we require more time, we will inform you of the reason and extension period in writing.
We will deliver our written response by mail or electronically, at your option.
Any disclosures we provide will only cover the 12-month period preceding the verifiable consumer request's receipt. The response we provide will also explain the reasons we cannot comply with a request, if applicable. For data portability requests, we will select a format to provide your personal information that is readily useable and should allow you to transmit the information from one entity to another entity without hindrance.
We do not charge a fee to process or respond to your verifiable consumer request unless it is excessive, repetitive, or manifestly unfounded. If we determine that the request warrants a fee, we will tell you why we made that decision and provide you with a cost estimate before completing your request.
Personal Information Sales
We will not sell your personal information to any party. If in the future, we anticipate selling your personal information to any party, we will provide you with the opt-out and opt-in rights required by the CCPA.
We will not discriminate against you for exercising any of your CCPA rights. Unless permitted by the CCPA, we will not:
- Deny you goods or services.
- Charge you different prices or rates for goods or services, including through granting discounts or other benefits, or imposing penalties.
- Provide you a different level or quality of goods or services.
- Suggest that you may receive a different price or rate for goods or services or a different level or quality of goods or services.
Other California Privacy Rights
California's "Shine the Light" law (Civil Code Section § 1798.83) permits users of our Website that are California residents to request certain information regarding our disclosure of personal information to third parties for their direct marketing purposes. To make such a request, please send an email to [Email].
Changes to Our Privacy Notice
We reserve the right to amend this privacy notice at our discretion and at any time. When we make changes to this privacy notice, we will post the updated notice on our Website and update the notice's effective date. Your continued use of our Website following the posting of changes constitutes your acceptance of such changes.
Contact Information
If you have any questions or comments about this notice, the ways in which we collect and use your information described below and in our Privacy Policy, your choices and rights regarding such use, or wish to exercise your rights under California law, please do not hesitate to contact us at:
- Phone:
- Website:
- Email:

subset: commoncrawl


text:
Available for:
iPad, iPhone, Android, Mac, and Windows.
The KJV with Strong's Numbers includes the text of the KJV and Olive Tree's Enhanced Strong's Dictionary (with words in both the original language and transliterated form).
Video: How Strong's Tagged Bibles work in the Olive Tree Bible App
The King James Version (KJV) is an English translation of the Holy Bible, commissioned for the benefit of the Church of England at the behest of King James I of England. First published in 1611, it has had a profound impact not only on most English translations that have followed it, but also on English literature as a whole.
The KJV Bible text can be viewed with or without the inline Strong's. When only the text is displayed on the screen, the user simply taps a word to display the dictionary information. When the text and the numbers are displayed, tapping a number will accomplish the same thing.
Used in Olive Tree's apps, the Strong's numbers can be used to generate powerful search results essentially equivalent to what Strong's Exhaustive Concordance and Wigram's Englishman's Greek and Hebrew Concordances provide.
An excellent resource for readers who want to go a little farther in their study of the scriptures. From Online Bible with permission.


text:
Westboro Baptist Church founder Rev. Fred Phelps Sr. is in hospice care and near death, according to family and church members say. His estranged son says the longtime pastor's passing would put his followers in a crisis, because the church's members "think that death is a judgment from God."
"So far, that illusion has held because none of them has passed," Nathan Phelps continues.
The church's members are convinced they will be taken up by Jesus Christ, he tells the newspaper. "They're clear about that, that they're not going to feel the sting of death," he says.
Phelps says if that belief isn't borne out, the church's members will likely see it as a test of their faith. He predicted that some would find a "palatable justification" to continue on with Westboro Baptist.
News that the founder of the church known for using controversial funeral protests to carry out a campaign against gays and other groups was in hospice care came out , along with a statement from Phelps that his 84-year-old father had been excommunicated last summer from the church he built.
Fred Phelps Sr. "is now on the edge of death at Midland Hospice house in Topeka, Kansas," Nathan Phelps wrote in . He also said church members were preventing him and others who have broken with the family over the church's teachings from seeing the ailing pastor.
The reason for Fred Phelps' excommunication isn't known. A church spokesman interviewed by the Capital-Journal didn't deny the action, but he refused to elaborate. Another of Phelps' sons contacted the newspaper to say its version of events was accurate.
Nathan Phelps in a phone interview Sunday night that church members had voted Phelps out of the church "after some kind of falling out."
He added that Fred Phelps and his wife were moved out of the space they had long occupied above the church and into a nearby house. Afterward, the church founder stopped eating and drinking, the younger Phelps said.
The AP reports that Nathan Phelps "said he has no doubt some people would want to protest his father's funeral but added, 'I wish they wouldn't.' "
The possibility that Fred Phelps might die has led to questions over how Westboro Baptist might continue, and whether the church's followers would persist in their attempts to garner publicity for their views at funerals and other events.
A look at the church's website shows no break in its "Picket Schedule," which lists upcoming shows by the singer Lorde and comedian Kathy Griffin as targets. The site also features a video titled "Aye, God Hates St. Patrick's Day," featuring spokesman Steven Drain, who is mentioned by Nathan Phelps as a possible successor to his father.
On Sunday, Drain told that Westboro Baptist doesn't have a central leader. "The Lord Jesus Christ is our head," he told the newspaper.
Nathan Phelps says both his brother Tim and Drain have "shown the fire" that would be required of the church's pastor. But he also tells the Capital-Journal that several long-time church members "could get up and do the same job as the old man has done. They've heard [the preachings] a million times."
To see more documents/articles regarding this group/organization/subject click here.


text:
Specialist Home Elevator Installations in Chinese Quarter
Chinese Quarter Home lifts for Sale
Baker Stairlifts has aided thousands of Chinese Quarter residents adapt their homes with platform lifting solutions.
Our experienced Chinese Quarter home elevator installers cover the whole of the UK. With thousands of satisfied customers, the independence and freedom that a Baker Stairlifts home lift adaption provides are simply priceless. We truly believe it is our dedication, care and support that makes Baker Stairlifts the company you can trust.
Your Local Home Lift Company in Chinese Quarter
Baker Stairlifts can provide a free home visit to talk through the best options for your individual needs and space. Call us today on 0800 046 3130 for more information.
Upgrade your home's accessibility with one of our affordable and attractive home lifts, so you can continue to live happily in the home that means so much to you and your family.
Our specialist home elevators in Chinese Quarter adapt your residential property with minimal disruption at a fraction of the cost of moving.
Call Chinese Quarter 0800 046 3130 for a FREE Home Lift quote
Why choose Baker Stairlifts for your Home Lift in Chinese Quarter?
We understand that our customers would like a range of choices and options available to them with their home lift installations.
Over the years, Baker Stairlifts has dealt with many bespoke options for Chinese Quarter home lifts, giving us a great deal of experience with both little and large home lift projects, using the best and most cost-effective solutions.
Our home elevator services in Chinese Quarter include:
- Quick Installations
- 2 Years Full Warranty
- Buy Back Policy
- FREE Survey & Quote
- Huge Choice of Homelifts
- Lowest Price Guaranteed
- Top Quality Homelifts
- Extended Warranties
- Friendly Team
- Bespoke Options
For a FREE Home Lift quote call Chinese Quarter 0800 046 3130
Trusted Chinese Quarter Home Lift Installation
Don't Delay, Get It Today
From the moment the decision was made within the month it was in. So pleased with it.
Great Service
Responded promptly to initial enquiry; engaged effectively thereafter; and delivered installation asShow More "Great Service"
Very Honest & Efficient
Very honest and efficient. We got exactly what we wanted and from start to finish it was less than aShow More "Very Honest & Efficient"
Well Served
We enquired about stairlifts and were directed to . They responded rapidly with a survey and what seemed to us a reasonable quote. We accepted the quote and the stairlift was promptly fitted with a minimum of fuss. We are delighted with theShow More "Well Served"
Sourcing Through to Installation
Stairlift Satisfaction
What are home lift prices in Chinese Quarter?
The price for a new installation of Home Lifts depends on a number of factors:
- The size of the area requiring work
- the age of the structure
- Additional features required
- How easy the area is to access
- The condition of the current area
- Many other factors...
The best method is for us to arrange a free no-obligation survey of your Chinese Quarter location. We can then put together the best, most accurate price quote for a new senior stairlift in Chinese Quarter.
Benefits of Installing a Home Lift in Chinese Quarter
Easily Accessible
All our Chinese Quarter home lifts have level access making it easy to enter and exit for wheelchair users or walking passengers without the need for a pit or ramp. A power operated door is also available as an optional extra.
Space-Saving Design
Our home lifts in Chinese Quarter have a compact footprint and no obtrusive side posts thanks to a unique design featuring only rear space-saving posts.
Our Chinese Quarter traction drive home lifts have low running costs – less than 1 pence per day. Powered electronically, the system is clean and environmentally friendly, requiring 56% less power to run than a hydraulic home lift system.
Powerful Lifting Capability
Our homelifts can transport up to 255kg a time making them ideal for transporting wheelchair users and their carer at the same time.
Easy to Operate
Illuminated controls come as standard to make the lifts easy to navigate. Remote control call stations, in-cabin telephones and diagnostic displays are available in all home lifts in Chinese Quarter.
Smooth and Quiet Operation
Our soft start/stop facility comes as standard on all home lifts, giving users a gentle ride without unwanted judders or bumps. The traction drive system is quieter by up to 19%.
Safety Features
In the event of a power cut, a battery back-up ensures that the lift will finish its journey allowing passengers to exit the lift safely. Sensors to the top, bottom and sides of the lift detect any obstructions and bring the lift to a safe stop automatically.
Find Out If We Offer Home Lift Services in Your Area
Find out why Baker Stairlifts are one of the leading Homelift Suppliers with some of the best UK prices.
For a home survey quote – enter your postcode to see if we have engineers in your area for a simple homelift quote:
Get a FREE Home lift Quote in Chinese Quarter
Enter your details below and one of our experienced Baker Stairlifts representatives will contact you to arrange a home survey and provide you with a FREE no obligation quotation.
"*" indicates required fields
Looking for a service other than Home lifts in Chinese Quarter?
We provide a whole range of mobility options for our Chinese Quarter clients:
Not in Chinese Quarter? Still looking for "Home lift near me...?"
We have years of experience providing our Chinese Quarter clients with Home Lifts, however we also cover many other regions:
Frequently Asked Questions - Home Lifts in Chinese Quarter
Most manufacturers issue a maximum carrying weight of 19 stones (127kg), although at Baker Stairlifts we are able to supply heavy duty stairlifts which can carry up to 30 stone (190kg). Modern day stairlifts are very quiet and cannot be heard through adjoining walls. A stairlift is a mechanical device for lifting people and wheelchairs up and down stairs. For sufficiently wide stairs, a rail is mounted to the treads of the stairs. A chair or lifting platform is attached to the rail. A person on the chair or platform is lifted as the chair or platform moves along the rail. (Definition from Wikipedia http://en.wikipedia.org/wiki/Stairlift) YES. A new stairlift comes with a minimum 12 month manufacturers parts and labour warranty. In addition to this Baker Stairlifts will provide all our customers with the option to purchase extended warranties at the end of this 12 month period. One of our engineers will advise whether a stairlift can be fitted into your home during a FREE, NO OBLIGATION survey and quotation. Baker Stairlifts guarantee to attend to your breakdown within 24 hours, but normally any breakdown would be covered in 2-3 hours. Yes, the majority of stairlift motors are powered by Direct Current (24volt), which automatically charge when not in use. Therefore, the stairlift will work normally during a power cut. The minimum width of your staircase should be 660mm (26 inches) in order to accommodate a stairlift. This would also be dependent on the weight and size of the user of the lift. As you might expect, pricing will vary depending on which type of stairlift you need to buy. Typically, independent dealers can be cheaper than manufacturers. At Baker Stairlifts straight stairlifts will generally be priced from £1495 for a brand new stairlift, with a new curved stairlift being slightly more starting at £2495. Of course, these prices are just guidelines as the size and shape of your staircase will be taken into consideration. Our engineers are fully experienced and can install and demonstrate a straight stairlift in under two hours. However, a curved stairlift may take three to four hours to install under normal circumstances. We will be able to give you a better idea when you place your order with us and we have assessed the complexity of the job. This depends on what we are installing. However, in broad terms, we can deliver a straight stairlift between 2-7 working days and a curved stairlift in around 15-20 working days. Of course, in some cases for a standard straight stairlift we will have stock available instantly and could arrange installation the very next day. We will be able to advise you of the likely installation time when you place your order. Yes. When you stairlift is not in use it can be folded away and parked at the top or bottom of the staircase allowing full access for other householders.


text:
Sugar Coated Green Fluorite 2
- In stock, ready to ship
- Inventory on the way
We offer affordable flat rate shipping to the following countries that we ship to:
Courier: Qxpress
Shipping Time: 1-2 days Business Days
Free on $88 or just $3
Courier: Aramex
Shipping Time: 4-7 Business Days
Flat Rate: $22 AUD
Courier: Qxpress
Shipping Time: 8-12 Business Days
Flat Rate: 20 MYR
Hong Kong
Courier: Aramex
Shipping Time: 2-3 Business Days
Flat Rate: $108 HKD
South Korea
Courier: TNT
Shipping Time: 3-4 Business Days
Flat Rate: ₩ 18000 WON
United States
Shipping Company: Janio
Shipping Time: 8-15 Business Days
Flat Rate: $20 USD
*Unforeseen shipping delays may occur during the festive season as well as given the covid situation
This is an option designed to help you save on shipping fees.
Essentially, to keep an 'open box' is to have your all your items from multiple orders across our store's product releases, shipped in a single parcel.
For international customers, use this option with our flat rate shipping to save even more on shipping (hooray!)
Only use this option only if you're not in a hurry, or have a deadline, to receive your items.
How It Works
You get to enjoy a maximum of 15 days period to keep your box open, starting from the date of your first order. Under an open box, all your orders will only ship once you are ready to do so, or when the 15 days period has reached.
Leave a note at checkout 'keep this order as open box', or 'close my box', to inform us.
As all our items are one of a kind, any change of mind or item swaps are strictly not allowed.
Read full details HERE.
• I use my abilities as an energy healer to energetically cleanse each crystal that goes to you, of negative energy, and heal any energetic damage that it has. It's highly recommended that you cleanse them on your own regularly.
• My journey with raw crystals has taught me to learn to accept their 'imperfections', just as how we should accept our own. After all, everything created by mother nature is already whole and perfect in itself.
Remember the magic that lies within you
Reawaken to the true power that lies with you
May your heart awaken to pure love, and your spirit bloom to its highest potential
I hope crystals serve as tools and companions to journey through life, and finding your way home to your true self


text:
Monads as containers
There now exists a translation of this article into Russian!
A monad is a container type together with a few methods defined on it. Monads model different kinds of computations.
Like Haskell lists, all the elements which a monadic container holds at any one time must be the same type (it is homogeneous).
There are a few ways to choose the basic set of functions that one can perform
on these containers to be able to define a monad. Haskell generally uses a
pair of functions called pure
(return = pure
) and monadic
bind (>>=)
, but it is more natural sometimes to begin with fmap
and join
, as these are simpler
to understand at first. We can later define bind in terms of these.
The first of these three, generally called map, (but called fmap
Haskell 98) actually comes from the definition of a functor. We can think
of a functor as a type of container where we are permitted to apply a single
function to every object in the container.
That is, if f
is a functor, and we are given a function of type (a -> b)
and a container of type (f a)
, we can get a new container of type (f b)
This is expressed in the type of fmap
fmap :: (Functor f) => (a -> b) -> f a -> f b
If you will give me a blueberry for each apple I give you (a -> b)
, and I have a box of apples (f a)
, then I can get a box of blueberries (f b)
Every monad is a functor.
The second method, return, is specific to monads. If m
is a monad, then
return takes an element of type a
, and gives a container of type (m a)
with that element in it. So, its type in Haskell is
return :: (Monad m) => a -> m a
If I have an apple (a)
then I can put it in a box (m a)
The third method, join, also specific to monads, takes a container of
containers m (m a)
, and combines them into one m a
in some sensible
fashion. Its Haskell type is
join :: (Monad m) => m (m a) -> m a
If I have a box of boxes of apples (m (m a))
then I can take the apples from each, and put them in a new box (m a)
From these, we can construct an important operation called bind or
extend, which is commonly given the symbol (>>=)
. When you define your
own monad in Haskell, it will expect you to define just return and bind. It
turns out that mapping and joining come for free from these two. Although only
return and bind are needed to define a monad, it is usually simpler to think
about map, return, and join first, and then get bind from these, as map and
join are in general simpler than bind.
What bind does is to take a container of type (m a)
and a function of type
(a -> m b)
. It first maps the function over the container, (which would give
an m (m b)
) and then applies join to the result to get a container of type
(m b)
. Its type and definition in Haskell is then
(>>=) :: (Monad m) => m a -> (a -> m b) -> m b
xs >>= f = join (fmap f xs)
-- how we would get bind (>>=) in Haskell if it were join and fmap
-- that were chosen to be primitive
If I have a box of apples (m a)
and for each apple, you will give me a box of blueberries (a -> m b)
then I can get a box with all the blueberries together (m b)
Note that for a given container type, there might be more than one way to define these basic operations (though for obvious reasons, Haskell will only permit one instance of the Monad class per actual type). [Technical side note: The functions return and bind need to satisfy a few laws in order to make a monad, but if you define them in a sensible way given what they are supposed to do, the laws will work out. The laws are only a formal way to give the informal description of the meanings of return and bind I have here.]
It would be good to have a concrete example of a monad at this point, as these functions are not very useful if we cannot find any examples of a type to apply them to.
Lists are most likely the simplest, most illustrative example. Here, fmap
is just the usual map
, return
is just (\x -> [x])
and join
is concat
instance Monad [] where
--return :: a -> [a]
return x = [x] -- make a list containing the one element given
--(>>=) :: [a] -> (a -> [b]) -> [b]
xs >>= f = concat (map f xs)
-- collect up all the results of f (which are lists)
-- and combine them into a new list
The list monad, in some sense, models computations which could return any number of values. Bind pumps values in, and catches all the values output. Such computations are known in computer science as nondeterministic. That is, a list [x,y,z] represents a value which is all of the values x, y, and z at once.
A couple examples of using this definition of bind:
[10,20,30] >>= \x -> [x, x+1]
-- a function which takes a number and gives both it and its
-- successor at once
= [10,11,20,21,30,31]
[10,20,30] >>= \x -> [x, x+1] >>= \y -> if y > 20 then [] else [y,y]
= [10,10,11,11,20,20]
And a simple fractal, exploiting the fact that lists are ordered:
f x | x == '#' = "# #"
| otherwise = " "
"#" >>= f >>= f >>= f >>= f
= "# # # # # # # # # # # # # # # #"
You might notice a similarity here between bind and function application or composition, and this is no coincidence. The reason that bind is so important is that it serves to chain computations on monadic containers together.
You might be interested in how, given just bind and return, we can get back to map and join.
Mapping is equivalent to binding to a function which only returns containers
with a single value in them -- the value that we get from the function of
type (a -> b)
which we are handed.
The function that does this for any monad in Haskell is called liftM
-- it
can be written in terms of return and bind as follows:
liftM :: (Monad m) => (a -> b) -> m a -> m b
liftM f xs = xs >>= (return . f)
-- take a container full of a's, to each, apply f,
-- put the resulting value of type b in a new container,
-- and then join all the containers together.
Joining is equivalent to binding a container with the identity map. This is
indeed still called join
in Haskell:
join :: (Monad m) => m (m a) -> m a
join xss = xss >>= id
It is common when constructing monadic computations that one ends up with a large chain of binds and lambdas. For this reason, some syntactic sugar called "do notation" was created to simplify this process, and at the same time, make the computations look somewhat like imperative programs.
Note that in what follows, the syntax emphasizes the fact that the list monad
models nondeterminism: the code y <- xs
can be thought of as y
taking on
all the values in the list xs
at once.
The above (perhaps somewhat silly) list computations could be written:
do x <- [10,20,30]
[x, x+1]
do x <- [10,20,30]
y <- [x, x+1]
if y > 20 then [] else [y,y]
The code for liftM could be written:
liftM f xs = do a <- xs
return (f a)
If you understood the above, then you have a good start on understanding monads in Haskell. Check out Maybe (containers with at most one thing in them, modelling computations that might not return a value) and State (modelling computations that carry around a state parameter using an odd sort of container described below), and you'll start getting the picture as to how things work.
A good exercise is to figure out a definition of bind and return (or fmap, join and return) which make the following tree type a monad. Just keep in mind what they are supposed to do.
data Tree a = Leaf a | Branch (Tree a) (Tree a)
For more good examples of monads, and lots of explanation see All About Monads which has a catalogue of the commonest ones, more explanation as to why you might be interested in monads, and information about how they work.
The question that many people will be asking at this point is "What does this all have to do with IO?".
Well, in Haskell, IO is a monad. How does this mesh with the notion of a container?
Consider getChar :: IO Char
-- that is, an IO container with a character
value in it. The exact character that the container holds is determined when
the program runs by which keys the user presses. Trying to get the character
out of the box will cause a side effect: the program stops and waits for the
user to press a key. This is generally true of IO values - when you get a
value out with bind, side effects can occur. Many IO containers don't
actually contain interesting values. For example,
putStrLn "Hello, World!" :: IO ()
That is, the value returned by putStrLn "Hello, World!"
is an IO container
filled with a value of type ()
, a not so interesting type. However, when
you pull this value out during a bind operation, the string Hello, World!
is printed on the screen. So another way to think about values of type IO t
is as computations which when executed, may have side effects before
returning a value of type t.
One thing that you might notice as well, is that there is no ordinary Haskell
function you can call (at least not in standard Haskell) to actually get a
value out of an IO container/computation, other than bind, which puts it right
back in. Such a function of type IO a -> a
would be very unsafe in the pure
Haskell world, because the value produced could be different each time it was
called, and the IO computation could have side effects, and there would be no
way to control when it was executed (Haskell is lazy after all). So how do IO
actions ever get run? The IO action called main
runs when the program is
executed. It can make use of other IO actions in the process, and everything
starts from there.
When doing IO, a handy special form of bind when you just want the side effects and don't care about the values returned by the container on the left is this:
(>>) :: Monad m => m a -> m b -> m b
m >> k = m >>= \_ -> k
An example of doing some IO in do notation:
main = do putStrLn "Hello, what is your name?"
name <- getLine
putStrLn ("Hello " ++ name ++ "!")
or in terms of bind, making use of the special form:
main = putStrLn "Hello, what is your name?" >>
getLine >>= \name ->
putStrLn ("Hello " ++ name ++ "!")
or, very primitive, without the special form for bind:
main = putStrLn "Hello, what is your name?" >>= \x ->
getLine >>= \name ->
putStrLn ("Hello " ++ name ++ "!")
Another good example of a monad which perhaps isn't obviously a container at
first, is the Reader monad. This monad basically consists
of functions from a particular type: ((->) e)
, which might be written
(e ->)
if that were supported syntax. These can be viewed as containers
indexed by values of type e
, having one spot for each and every value of
type e
. The primitive operations on them follow naturally from thinking
this way.
The Reader monad models computations which read from (depend on) a shared environment. To clear up the correspondence, the type of the environment is the index type on our indexed containers.
type Reader e = (->) e -- our monad
Return simply produces the container having a given value at every spot.
return :: a -> (Reader e a)
return x = (\k -> x)
Mapping a function over such a container turns out to be nothing more than what composition does.
fmap :: (a -> b) -> Reader e a -> Reader e b
= (a -> b) -> (e -> a) -> (e -> b)
-- by definition, (Reader a b) = (a -> b)
fmap f xs = f . xs
How about join? Well, let's have a look at the types.
join :: (Reader e) (Reader e a) -> (Reader e a)
= (e -> e -> a) -> (e -> a) -- by definition of (Reader a)
There's only one thing the function of type (e -> a)
constructed could
really be doing:
join xss = (\k -> xss k k)
From the container perspective, we are taking an indexed container of indexed
containers and producing a new one which at index k
, has the value at index
in the container at index k
So we can derive what we want bind to do based on this:
(>>=) :: (Reader e a) -> (a -> Reader e b) -> (Reader e b)
= (e -> a) -> (a -> (e -> b)) -> (e -> b) -- by definition
xs >>= f = join (fmap f xs)
= join (f . xs)
= (\k -> (f . xs) k k)
= (\k -> f (xs k) k)
Which is exactly what you'll find in other definitions of the Reader monad.
What is it doing? Well, it's taking a container xs
, and a function f
the values in it to new containers, and producing a new container which at
index k
, holds the result of looking up the value at k
in xs
, and then
applying f
to it to get a new container, and finally looking up the value
in that container at k
The Monads as computation perspective makes the purpose of such a monad perhaps
more obvious: bind is taking a computation which may read from the environment
before producing a value of type a
, and a function from values of type a
to computations which may read from the environment before returning a value
of type b
, and composing these together, to get a computation which might
read from the (shared) environment, before returning a value of type b
How about the State monad? Although I'll admit that with State and IO in particular, it is generally more natural to take the view of Monads as computation, it is good to see that the container analogy doesn't break down. The state monad is a particular refinement of the reader monad discussed above.
I won't go into huge detail about the state monad here, so if you don't already know what it's for, what follows may seem a bit unnatural. It's perhaps better taken as a secondary way to look at the structure.
For reference to the analogy, a value of type (State s a)
is like a
container indexed by values of type s
, and at each index, it has a value of
type a
and another, new value of type s
. The function runState
this "lookup".
newtype State s a = State { runState :: (s -> (a,s)) }
What does return do? It gives a State
container with the given element at
every index, and with the "address" (a.k.a. state parameter) unchanged.
return :: a -> State s a
return x = State (\s -> (x,s))
Mapping does the natural thing, applying a function to each of the values of
type a
, throughout the structure.
fmap :: (a -> b) -> (State s a) -> (State s b)
fmap f (State m) = State (onVal f . m)
where onVal f (x, s) = (f x, s)
Joining needs a bit more thought. We want to take a value of type
(State s (State s a))
and turn it into a (State s a)
in a natural way.
This is essentially removal of indirection. We take the new address and new
box that we get from looking up a given address in the box, and we do another
lookup -- note that this is almost the same as what we did with the reader
monad, only we use the new address that we get at the location, rather than
the same address as for the first lookup.
So we get:
join :: (State s (State s a)) -> (State s a)
join xss = State (\s -> uncurry runState (runState xss s))
I hope that the above was a reasonably clear introduction to what monads are about. Feel free to make criticisms and ask questions.