Human Reproduction NEET Quiz

The extraembryonic or foetal membranes are amnion, chorion, allantois and Yolk sac. Amnion is formed from mesoderm on outer side and ectoderm on inner side. Chorion is formed from trophoectoderm and mesoderm whereas allantois and Yolk sac membrane have mesoderm on outerside and endoderm in inner side.

Spermiogenesis is transformation of spermatids into spermatozoa whereas spermiation is the release of the sperms from sertoli cells into the lumen of seminiferous tubule.

Placenta 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 growth of body of mother and breast. Progesterone maintains pregnancy, keeps the uterus silent by increasing uterine threshold to contractile stimuli.

Hypothalamus secretes GnRH which stimulates anterior pituitary gland for the secretion of gonadotropins (FSH and LH).

Capacitation is increase in fertilising capacity of sperms which occurs in female reproductive tract.

Pathway of transport of sperms in human male is Rete testis – Efferent ductules (Vasa efferentia) -Epididymis -Vas deferens.

Hormones secreted by placenta are hCG, hPL, estrogen and progesterone.

• Fertilization in human is practically feasible only if the sperms and ovum are transported simultaneously at ampullary-isthmic junction.

Inhibin is produced by granulosa cells in ovary and has direct effect on the secretion of FSH.

High level is of estrogen and progesterone give negative feedback to hypothalamus for the release of GnRH.

In follicular phase of menstrual cycle, LH and FSH increase gradually.

Any extra uterine pregnancy is ectopic pregnancy. Implantation can occur in the wall of abdominal cavity, ovaries but 90-95% of ectopic pregnancies are tubal pregnancy where implantation occurs in fallopian tube.

In 28 days reproductive cycle, ovulation occurs on 14th day due to LH surge. In the mid cycle, the level of FSH and estrogen are also high. The female gamete is released from the ovary in secondary oocyte stage after completing meiosis I.

In human females, meiosis II is completed after the entry of sperm into the cytoplasm of secondary oocyte at the time of fertilisation leading to the formation of ovum and IInd polar body.

Zona pellucida is a non-cellular membrane made up of glycoproteins. It is secreted by secondary oocyte in Graafian follicle.

At the time of parturition, there is decrease in progesterone; release of prostaglandins and oxytocin, this will stimulate the contraction of smooth muscles of uterus.

Before the sperm can fertilize the ovum, it has to undergo capacitation and acrosomal reaction. Capacitation is a period of conditioning which occur in sperms starting from vagina. In this the cholesterol vesicles adhering the membrane surrounding the acrosome are removed.

Uterus is also called as hystera. So, removal of uterus is hysterectomy.

Spermatogonia are diploid.

Corpus luteum secretes progesterone (mainly) and some estrogen.

Progesterone maintains endometrium which is shed during menstruation due to low levels of progesterone.

Neurohypophysis (pars nervosa) also known as posterior pituitary, stores and releases two hormones oxytocin and vasopressin

hCG (= human chorionic gonadotropin) stimulates corpus luteum to secrete progesterone and estrogen.

Sperm is viable for 48-72 hours.

LH stimulates Leydig cells to secrete androgens.

Spermatogenesis requires 2.5°C lower than the body temperature.