question_answer

(i)   State whether the following statements are True (T) or False (F), correct the false ones.

(a) All sexually transmitted diseases are completely curable.

(b) Infertility is defined as the inability to produce a viable offspring and is always due to abnormalities or defects in the

(c) In ET techniques, embryos are always transferred into the uterus.

(ii)  What do you understand by the term test-tube baby?

OR

Study the flow chart given below. Give the name of the hormones involved at each stage and explain their role.

 

Answer:

(i) (a) False. No, all sexually transmitted diseases are not completely curable.

(b) False, often female is blamed for the couple being childless, but more often, the problem lies in male partner.

(c) False. In ET techniques, embryos upto 8-blastomeres are transferred into the fallopian tube ad embryos with more than 8-blastomere are transferred into the uterus.

(ii)  Test-tube baby means generation of an emrbyo from In-vitro fertilisation (IVF) technique. The ova of the wife/female donor and sperms from the husband/male donor are collected and are induced to form zygote unjder simulated conditions in the laboratory.

OR

(i) Rapid release ofLuteinising Hormone (LH) mptures Graafian follicle and release ovum (ovulation).

(ii) Corpus luteum secretes large amount of progesterone hormone that is essential for the maintenance of the endometrium required for implantation ofblastocyst leading to pregnancy.

(iii) Placenta produces several hormones like human Chorionic Gonadotropin (hCG), human Placental Lactogen (hPL). Relaxin is also produced during later phase of pregnancy. Levels of other hormones like estrogen, progestogen, cortisol, prolactin and thyroxine also increase,which is essential for supporting foetal growth, metabolic changes in mother and maintenance of pregnancy.

(iv) Parturition signals originate from the fully developed foetus and the placenta that induce mild uterine contractions which triggers the release ofoxytocin form pituitary. Oxytocin acts on the uterine muscle causing stronger uterine contractions.