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Human Reproduction — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Reproduction5 Marks
Question
Study the following flow chart. Name the hormones involved at each stage. Explain their functions.
✓

Answer

Hypothalamus
$\downarrow$
Pituitary
$\downarrow$
Testes
$\downarrow$
Sperms
  1. Hypothalamus secretes gonadotropin-releasing hormone (GnRH), which stimulates the anterior pituitary gland to secrete gonadotropins like luteinizing hormone (LH) and follicle stimulating hormone (FSH).
  2. LH stimulates the Leydig cells of testes to secrete androgens (like testosterone), which control spermatogenesis.
  3. FSH acts on Sertoli cells of testes, which in response secrete certain factors necessary for spermiogenesis; the sperm heads become embedded in the sertoli cells.

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