NEET Practice Questions (MCQs) with Answers & Solutions

(3) Condoms should always be used during coitus to avoid STDs and AIDS. (page- 63)

(3) IUDs increase phagocytosis of sperms within the uterus and the Cu ions releases suppress sperm motility and the fertilising capacity of sperms. The hormone releasing IUDs make the uterus unsuitable for implantation and the cervix hostile to the sperms. (page-60)

(3)

I. MTPs are considered relatively safe during the first trimester, i.e., upto 12 weeks of pregnancy. Second trimester abortions are much more riskier.

II. MTPs are not used as a contraceptive method to get rid of unwanted pregnancies either due to casual unprotected intercourse or failure of the contraceptive used during coitus or rapes. MTPs are also essential in certain cases where continuation of the pregnancy could be harmful or even fatal either to the mother or to the foetus or both.

III. MTPs are not always surgical, sometimes oral contraceptives are helpful.

IV. MTPs conducted under unqualified doctors are illegal.

(page-62)

(1) Oral administration of small doses of either progestogens or progestogen–estrogen combinations is used in the form of tablets and hence are popularly called the pills. (Page-61)

(4)

(a) is correct because pills inhibit ovulation and implantation as well as alter the quality of cervical mucus to prevent or retard entry of sperms.

(b) is correct because in vasectomy, a small part of the vas deferens is removed or tied up through a small incision on the scrotum. This blocks sperm transport and thus conception.

(c) is correct as IUDs increase phagocytosis of sperms within the uterus and the Cu ions released suppress sperm motility and the fertilising capacity of sperms, make the uterus unsuitable for implantation and the cervix hostile to the sperms.

(page- 60)

(3) Oral administration of small doses of either progestogens or progestogen–estrogen combinations is a contraceptive method which inhibit ovulation and implantation by inhibiting the secretion of FSH and LH. (page-61)

(a) Periodic abstinence is a method in which the couples avoid or abstain from coitus from day 10 to 17 of the menstrual cycle when ovulation could be expected. As chances of fertilisation are very high during this fertile period. Therefore, by abstaining from coitus, conception could be prevented.

(b) Withdrawal or coitus interruptus is a method in which the male partner withdraws his penis from the vagina just before ejaculation so as to avoid insemination.

(c) Lactational amenorrhea (absence of menstruation) method is based on the fact that the cycle do not occur during the period of intense lactation following parturition. Therefore, as long as the mother breast-feeds the child fully, chances of conception are almost nil. (page- 59,60)

I. IUT: is a technique to help infertile people, the semen collected either from the husband or a healthy donor is artificially introduced either into the vagina or into the uterus of the female.

II. Birth control: Copper T is an IUD which increases phagocytosis of sperms within the uterus and the Cu ions released suppress sperm motility and the fertilising capacity of sperms.

III. Spermicides: agent to kill spermatozoa, are used along with condoms and other barriers to increase contraceptive efficiency.

IV. STD: VDRL stands for Venereal Disease Research Laboratory, is a blood test that detects an antibody that is present in the bloodstream when a patient has syphilis.

(1) IUDs are ideal contraceptives for the females who want to delay pregnancy and/or space children. It is one of most widely accepted methods of contraception in India. (page- 60,61)

This makes mutaion is the most important evolutionary agent as it introduces new alleles into the gene pool of a population increasing variation.