Sertoli cells are regulated by the pituitary hormone known as
FSH
GH
Prolactin
Prolactin
Withdrawal of which of the following hormones is the immediate cause of menstruation?
Eastrogens
FSH
FSH-RH
FSH-RH
The difference between spermiogenesis and spermiation is
In spermiogenesis spermatids are formed, while in spermiation spermatozoa are formed.
In spermiogenesis spermatozoa are formed, while in spermiation spermatids are formed.
In spermiogenesis spermatozoa are formed, while in spermiation spermatozoa are released from sertoli cells into the cavity of seminiferous tubules.
In spermiogenesis spermatozoa from sertoli cells are released into the cavity of seminiferous tubules, while in spermiation spermatozoa are formed.
Hormones secreted by the placenta to maintain pregnancy are
hCG, hPL, progestogens, prolactin
hCG, hPL, estrogens, relaxin, oxytocin
hCG, progestogens, estrogens, glucocorticoids
hCG, hPL, progestogens, estrogens
D.
hCG, hPL, progestogens, estrogens
The placenta is an endocrine gland that is only present during pregnancy. It releases human chorionic gonadotropic hormone (hCG) which stimulates the Corpus luteum during pregnancy to release estrogen and progesterone and also rescues corpus luteum from regression. Human placental lactogen (hPL) is involved in the growth of the body of mother and breast. Progesterone maintains pregnancy, keeps the uterus silent by increasing uterine threshold to contractile stimuli.
Match the items given in Column I with those in Column II and select the correct option given below :
column (i) | Column (ii) |
(a) Proliferative Phase | (i) Breakdown of endometrial lining |
(b) Secretory Phase | (ii) Follicular Phase |
(c) Menstruation | (iii) Luteal Phase |
a | b | c |
iii | ii | i |
a | b | c |
i | iii | ii |
a | b | c |
iii | i | ii |
a | b | c |
ii | iii | i |
The stage during which separation of the paired homologous chromosomes begins is
Pachytene
Diplotene
Zygotene
Diakinesis
Which of the following statements is correct?
Ovules are not enclosed by ovary wall in gymnosperms
Selaginella is heterosporous, while Salvinia is homosporous
Stems are usually unbranched in both Cycas and Cedrus
Horsetails are gymnosperms
Gastrula is the embryonic stage in which
Cleavage occurs
blastocoel forms
Germinal layers form
Villi form