Class 12th Biology 2017 Set2 Delhi Board Paper Solution
Name the hormones secreted and write their functions :
(i) By corpus luteum and placenta (any two).
(ii) During follicular phase and parturition
(i) Hormones secreted by corpus luteum
â Progesterone It converts the endometrium to its secretory stage and prepares the uterus for implantation.
â Oestradiol It acts as a growth hormone for tissue of the reproductive organs, supporting the vaginal lining, endometrium, etc. Hormones secreted by placenta â hCG Human Chorionic Gonadotropin. It stimulates and maintains the corpus luteum to secrete progesterone until the end of pregnancy.
â hCS Human Chorionic Somatomammotropin. It stimulates the growth of mammary glands during pregnancy.
(ii) Hormone secreted during follicular phase
â FSH Follicular Stimulating Hormone. It stimulates the ovarian follicles to secrete oestrogen. Hormone secreted during parturition
â Relaxin It increases the flexibility of pubis symphysis and helps in the dilation of uterine cervix during labour
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