Biology · Chemical Coordination and Integration · NEET
FSH is made and released by the anterior pituitary (pars distalis). The hypothalamus only makes GnRH, which tells the pituitary to release FSH and LH. Students mix this up because both glands are involved. Remember the chain: hypothalamus makes GnRH, GnRH goes to the pituitary, the pituitary then releases FSH and LH into the blood.
In females, FSH helps ovarian follicles grow and LH triggers ovulation and forms the corpus luteum. In males, FSH acts on the Sertoli cells to support sperm formation, while LH acts on the Leydig (interstitial) cells to make testosterone. Both are gonadotropins from the same gland, but they hit different target cells.
GnRH (gonadotropin releasing hormone) is a hypothalamic releasing hormone. In both males and females it stimulates the anterior pituitary to make and release FSH and LH. It is released in pulses, and in females the pulse frequency is controlled by circulating levels of estrogen and progesterone. So GnRH is not male-only; it drives reproduction in both sexes.
No. In males FSH acts on the Sertoli cells (which help make sperm), not the Leydig cells. LH is the one that acts on the Leydig (interstitial) cells to make androgens like testosterone. This is a classic NEET trap in assertion-reason questions.
Yes. In older or some textbooks LH in males is called ICSH (interstitial cell stimulating hormone) because it stimulates the interstitial Leydig cells to secrete androgens. NCERT uses LH for both sexes, so treat LH and ICSH as the same hormone.
Changes in GnRH pulse frequency in females is controlled by circulating levels of:
Assertion A: FSH acts upon ovarian follicles in female and Leydig cells in male. Reason R: Growing ovarian follicles secrete estrogen in female while interstitial cells secrete androgen in male human being. Choose the correct answer.
Arrange the sequence of different hormones for their role during gametogenesis. (A) Gonadotropin LH stimulates synthesis and secretion of Androgen (B) Gonadotropin releasing hormone from hypothalamus (C) Androgen stimulates spermatogenesis (D) Gonadotropin FSH helps in the process of spermiogenesis (E) Gonadotropins from anterior pituitary gland. Choose the correct answer.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
FSH and LH are produced by the pars distalis of the anterior pituitary (adenohypophysis). GnRH, which controls them, is produced by the hypothalamus.
FSH, LH and GnRH are all peptide/protein type hormones, not steroids. This means they act through membrane receptors, unlike estrogen and testosterone which are steroids.
A sharp surge of LH (the LH surge) triggers ovulation, the release of the egg from the mature Graafian follicle. FSH mainly helps the follicle grow before this.
Yes, both sexes have FSH and LH from the same anterior pituitary, but they act on different target cells: follicles/ovary in females and Sertoli/Leydig cells in the testis in males.
