Question

The female hormone inhibin is secreted by
A. Zona pellucida
B. Oviduct
C. Corpus luteum
D. Uterine epithelium

Answer 1

Hint: Inhibin reduces FSH production in humans. In gonads, pituitary gland, placenta, corpus luteum, granulosa cells, and other tissues, females develop this inhibitor while males secrete it from the Sertoli cells located within the testes.

Complete answer:Inhibin is a multifunctional hormone controlling the secretion of pituitary FSH. Inhibin is a gonadal messenger involved in the regulation of adverse feedback on FSH released from the pituitary gland.

Inhibin is a paracrine regulator of the ovaries and testicles. Its paracrine effects are currently used in the diagnosis of male and female infertility, gynecological, and gestational diseases in the uteroplacental unit. Inhibin is a glycoprotein formed by the ovary's granulosa and theca cells and by the testis' Sertoli cells. Two active molecular forms of inhibin exist: inhibin A Inhibin B Inhibin A and inhibin B are (inhibin A or βB (inhibin B) subunits and heterodimers formed by the alpha subunit. This prevents FSH secretion. Hormone inhibin is secreted by Granulosa cells and luteum corpus in women.
Hence, option C-Corpus luteum is the correct answer.

Note: Inhibin A and inhibin B are synthesized in human males and females at various times and from many different types of cells. Both suppress FSH production and demonstrate local paracrine effects in the gonads. Since puberty, the ovary and testis have been the primary organs producing inhibin A and inhibin B. Inhibin A is secreted predominantly by the corpus luteum and is involved during the luteal-follicular transition in the negative feedback regulation of FSH secretion. Inhibin B is in response to FSH secreted by antral follicles. Inhibin B level is thus a marker of ovarian activity. Inhibin B is a spermatogenesis marker. With age, its secretion decreases. The placenta primarily secretes Inhibin A, also formed by the corpus luteum, during pregnancy.