Term
| In step 1, What happens in the hypothalamus? |
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Definition
| The hypothalamus secretes GnRH. |
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Term
| In step 2, Where does the GnRH travel to, and how does it get there? |
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Definition
| GnRH passes through the blood (hypothalamohypophyseal portal) to the Anterior Pituitary gland (A.P.) |
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Term
| In step 3, what does GnRH do? |
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Definition
| GnRH stimulates the A.P. gland causing it to secrete two Gonadotropins. |
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Term
| What are the names of the two hormones created in step 3? |
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Definition
A.P. secretes L.H. & F.S.H.
L.H. = Leydig cell stimulating hormone.
F.S.H. = Forming sperm cell. |
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Term
| In step 4, where does each hormone travel to? |
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Definition
| L.H. & F.S.H. travel to the testes. Once they are there each hormone plays a different role. |
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Term
| In step 4a, What role does L.H. play in the testes? |
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Definition
L.H. binds to the leydig cells inside the testes surrounding the seminiferous tubules. & stimulates the leydig cells.
This causes the leydig cells to increase the rate of making testosterone & secreting testosterone. |
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Term
| Where does the testosterone end up traveling to from the leydig cells? |
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Definition
Testosterone passes through the blood & back to the hypothalamus.
Testosterone has a negative feedback on the hypothalamus which stops GnRH.
Testosterone has a negative feedback on the A.P. which reduceds L.H. & F.S.H. secretions. |
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Term
| In step 4b, What roles does the F.S.H. play in the testes? |
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Definition
F.S.H. binds to the sertoli cells inside the seminiferous tubules in the testes.
F.S.H stimulates the sertoli cells causing the sertoli cell to secrete Inhibin and to increase spermatogenesis. |
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Term
| Where does the Inhibin end up traveling to from the sertoli cells? |
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Definition
The inhibin passes to the A.P. gland.
Inhibin has a negative feedback effect on the A.P. which reduces the secretion F.S.H. |
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