Class 12th Biology 2017 Set1 Delhi Board Paper Solution
Arrange the following hormones in the sequence of their secretion in a pregnant woman.
Mention their source and the function they perform.
hcG ; LH ; FSH ; Relaxin (hPL)
(a) FSH, LH, hcG, (hPL)
(b)
hcG: If fertilization and implantation do occur, the corpus luetum is maintained by hcG, which takes the job of pituitary LH after fertilization.
Source: Placenta
LH: LH Act as the Leydigs cell and stimulates synthesis and secretion of androgens. Androgens stimulate the process of spermatogenesis.
In Females - FSH and LH affect the ovaries and uterus and the monthly cycle begins. Gonadotropins (LH and FSH) increase graually during the follicular phase and stimulates follicular development as well as secretion of estrogens by the following follicles.
Source: Anterior pituitary lob
FSH: It stimulate the follicles to produce estrogen and LH stimulates the corpus luetum to produce progestrone.
Source: Anterior pituitary lob
Relaxin (hPL): hcG, hPL and relaxin are produced in women only during pregnancy. In the later phase of pregnancy, a harmone called relaxin is also secreted by the ovary.
Source: Placenta
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