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19 Cards in this Set
- Front
- Back
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where can you find spermatogonia
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found in the walls of semniferous tubules
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what is the ploidy of spermatogonia
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diploid
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how does spermatogonia make more of itself
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by dviding by mitosis
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what happens to the spermatogonia that enlarges?
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it becomes the primary spermatocyte
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what is the ploidy of a primary spermatocyte
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diploid
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what undergoes the first division of meiosis
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spermatocytes
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what is the product of a primary spermatocyte undergoing meiosis 1
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2 haploid secondary spermatocytes
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what undergoes meiosis 2, what is the end result and ploidy?
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the two secondary spermatocytes undergo meiosis 2 and they produce 2 haploid spermatids (4 in total)
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how long is the process of creating a sperm
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65-95 days
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describe the structure of a mature sperm
name the 4 components and their purpose |
1. head- has nucleus and DNA
-also has acrosome on the surface-enzyme that helps sperm penetrate the egg 2. mid piece- bundle of mitochondria(ATP to move tail) 3. Tail- flagellum (9+2 arrangement of microtubules) |
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where can i find the sertoli cells?
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semniferous tubules
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what are the purpose of sertoli cells
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1. forms tight junctions
2. forms blood testes barrier 3. provides protection for the sperm against toxins 4. prevents sperm from secreting into the blood 5. provides nutrients for sperm(nurse cells) |
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what are androgens and give an example
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-principle sex hormone sin males
-testosterone is the most important one |
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how are androgens produces and secreted
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hypothalamus secretes GnRH every 2 hours which stimulates the ant. pit to produce Lh or FSH which stimulates interstitial cells to produce and secrete testosterone (androgen).
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what level of testosterone does spermatogenesis require
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high
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what are the side effects of not having high enough testosterone
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risk of sterility
regular 100million fertility impaired 35mill steril less that 20 mill |
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what are the actions of testosterone in the body
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1. adolescent growth spert
2. growth of primary/secondary male characteristics |
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what is the action of FSH during repro
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1. stimulates developement of semniferous tubules
2. stimulates sertoli cells to produce and secrete androgen binding proteins |
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what hormone inhibits FSH secretion
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inhibin (peptide hormone secreted by sertoli cells)
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