ABP stands for "Androgen-binding protein". ABP is a glycoprotein (beta-globulin) produced by the Sertoli cells in the seminiferous tubules of the testis. ABP causes testosterone to bind with spermatocyte cells (spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids). Testosterone is necessary for proper sperm production.
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Q: Does LH and FSH come from the anterior or posterior portion of the pituitary gland? Answer: Both FSH and LH are synthesized by cells within the anterior pituitary gland. GnRH is produced by cells of the hypothalamus. From Wikipedia... The anterior pituitary contains five types of endocrine cell, and they are defined by the hormones they secrete:
Q: What is the composition of prostatic fluid, the fluid produced and released by the prostate gland? Answer (from Wikipedia)... The function of the prostate is to secrete a slightly alkaline fluid, milky or white in appearance, that in humans usually constitutes roughly 30% of the volume of the semen along with spermatozoa and seminal vesicle fluid.[4]Semen is made alkaline overall with the secretions from the other contributing glands, including, at least, the seminal vesicle fluid.[5] The alkalinity of semen helps neutralize the acidity of the vaginal tract, prolonging the lifespan of sperm. The prostatic fluid is expelled in the firstejaculate fractions, together with most of the spermatozoa. In comparison with the few spermatozoa expelled together with mainly seminal vesicular fluid, those expelled in prostatic fluid have better motility, longer survival and better protection of the genetic material. In human prostatic secretions, the protein content is less than 1% and includes proteolytic enzymes, prostatic acid phosphatase, beta-microseminoprotein, andprostate-specific antigen. The secretions also contain zinc with a concentration 500–1,000 times the concentration in blood. The Kermode bear /ˈkɜːrˌmoʊdi/ (Ursus americanus kermodei), also known as the "spirit bear" (particularly in British Columbia), is a subspecies of the American black bear living in the Central and North Coast regions of British Columbia, Canada.[1] It is the official provincial mammal of British Columbia.[2] It is noted for about 1⁄10 of their population having white or cream-coloured coats. This colour is due to a double recessive gene unique in the subspecies. They are not albinos[1] and not any more related to polar bears or the "blonde"brown bears of Alaska's "ABC Islands" than other members of their species. Sometimes, a black mother can have a white cub. From Wikipedia... Oculocutaneous albinism is generally the result of the biological inheritance of genetically recessive alleles (genes) passed from both parents of an individual for example OCA1 (a gene on chromosome 11) and OCA2 (a gene on chromosome 15). A mutation in the human TRP-1 gene (on chromosome 9) may result in the deregulation of melanocyte tyrosinase enzymes, a change that is hypothesized to promote brown versus black melanin synthesis, resulting in a third oculocutaneous albinism (OCA) genotype, ″OCA3″.[12] Some rare forms are inherited from only one parent. There are other genetic mutations which are proven to be associated with albinism. All alterations, however, lead to changes in melanin production in the body.[8][13] Some of these are associated with increased risk of skin cancer (see list of such genetic variations). The chance of offspring with albinism resulting from the pairing of an organism with albinism and one without albinism is low. However, because organisms (including humans) can be carriers of genes for albinism without exhibiting any traits, albinistic offspring can be produced by two non-albinistic parents. Albinism usually occurs with equal frequency in both sexes.[8] An exception to this is ocular albinism, which it is passed on to offspring through X-linked inheritance. Thus, ocular albinism occurs more frequently in males as they have a single X and Y chromosome, unlike females, whose genetics are characterized by two X chromosomes.[14] There are two different forms of albinism: a partial lack of the melanin is known as hypomelanism, or hypomelanosis, and the total absence of melanin is known as amelanism or amelanosis. The enzyme defect responsible for OCA1-type albinism is tyrosine 3-monooxygenase (tyrosinase), which synthesizes melanin from the amino acid tyrosine. From Wikipedia... Tooth enamel is one of the four major tissues that make up thetooth in humans and many other animals, including some species of fish. It makes up the normally visible part of the tooth, covering the crown. The other major tissues are dentin,cementum, and dental pulp. It is a very hard, white to off white, highly mineralised substance that acts as a barrier to protect the tooth but can become susceptible to degradation, especially by acids from food and drink. Enamel is the hardest substance in the human body and contains the highest percentage of minerals,[1] 96%, with water and organic material composing the rest.[2] The primary mineral is hydroxyapatite, which is a crystalline calcium phosphate.[3]Enamel is formed on the tooth while the tooth is developing within the gum, before it erupts into the mouth. Once fully formed, it does not contain blood vessels or nerves. In humans, enamel varies in thickness over the surface of the tooth, often thickest at the cusp, up to 2.5 mm, and thinnest at its border with the cementum at the cementoenamel junction (CEJ). Enamel does not contain collagen, as found in other hard tissues such as dentin and bone, but it does contain two unique classes of proteins:amelogenins and enamelins. While the role of these proteins is not fully understood, it is believed that they aid in the development of enamel by serving as a framework for minerals to form on, among other functions.[5] Once it is mature, enamel is almost totally without the softer organic matter. Enamel is avascular and has no nerve supply within it and is not renewed, however, it is not a static tissue as it can undergo mineralization changes. Q: What controls the rate red blood cells are created? Answer: This question was the last question that stumped me during Term 1 session. I am sure that there will be many more excellent questions that stump me as Biology students push their knowledge to new limits! According to Wikipedia, ... Erythropoiesis (from Greek 'erythro' meaning "red" and 'poiesis' meaning "to make") is the process which produces red blood cells (erythrocytes). It is stimulated by decreased O2 in circulation, which is detected by the kidneys, which then secrete the hormone erythropoietin.[2]This hormone stimulates proliferation and differentiation of red cell precursors, which activates increased erythropoiesis in the hemopoietic tissues, ultimately producing red blood cells.[2] Q: Is there a link between urea and gout? Answer: Yes! From Wikipedia, gout... "is caused by elevated levels of uric acid in the blood. The uric acid crystallizes, and the crystals deposit in joints, tendons, and surrounding tissues... The crystallization of uric acid, often related to relatively high levels in the blood, is the underlying cause of gout. Uric acid is a product of the metabolic breakdown of purine nucleotides. This can occur for a number of reasons, including diet, genetic predisposition, or underexcretion of urate, the salts of uric acid.[5] Underexcretion of uric acid by the kidney is the primary cause of hyperuricemia in about 90% of cases, while overproduction is the cause in less than 10%.[9]About 10% of people with hyperuricemia develop gout at some point in their lifetimes. Dietary causes account for about 12% of gout,[5] and include a strong association with the consumption of alcohol, fructose-sweetened drinks, meat, and seafood.[7][11] Other triggers include physical traumaand surgery.[9] Studies in the early 2000s have found that other dietary factors once believed associated are, in fact, not.[12][13] Specifically, moderate consumption of purine-rich vegetables (e.g. beans, peas, lentils, and spinach) are not associated with the development of gout.[14] Neither is total consumption of protein.[12][14] Alcohol consumption is a factor, with wine presenting somewhat less of a risk than beer and spirits.[15] The consumption of coffee, vitamin C, and dairy products, as well as physical fitness, appear to decrease the risk.[16][17][18] This is believed to be partly due to their effect in reducing insulin resistance.[18]" Q: What is the difference between denature and denatured alcohol? Answer: Denature, according to Google, basically means to "wreck"... ...and as you can see from above, the definition also covers "denatured alcohol"! By denaturing alcohol, it has been "wrecked" to dissuade mass consumption.
Q: Why do females who live together often experience a menstrual cycle at a similar time of month? Answer: Debate continues as to why this seems to occur amongst some females living together, yet not with others. Wikipedia has this to offer on the topic... Hypothesized mechanisms of synchronization |
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