NCERT Exemplar Class 12 Biology Ch 3 Reproductive Health

Correct option: (c) ICSI.

Concept used. Assisted Reproductive Technologies (ART) are clinical methods that help infertile couples have a child. Each named technique differs only in what is transferred and where it is placed:

• ICSI (Intra Cytoplasmic Sperm Injection): a single sperm is injected directly into the cytoplasm of the ovum to form the zygote in the laboratory.
• GIFT (Gamete Intra Fallopian Transfer): an ovum collected from a donor is transferred into the fallopian tube of another female who cannot produce ova.
• ZIFT (Zygote Intra Fallopian Transfer): the zygote or early embryo (up to 8 blastomeres) is transferred into the fallopian tube.
• ET (Embryo Transfer): an embryo of more than 8 blastomeres is transferred into the uterus.

1. The question describes a sperm being put straight into the ovum. Match this against the definitions above: only ICSI involves direct injection of a sperm into the ovum.
2. Eliminate the distractors. (a) GIFT moves a gamete, not a sperm into an ovum. (b) ZIFT moves an already formed zygote. (d) ET moves an embryo. None of these is "inject a sperm into an ovum".

Option (c) ICSI: a sperm is injected directly into the ovum.

Correct option: (b) Result in decline in growth rate.

Concept used. IMR (Infant Mortality Rate) is the number of infant deaths (under one year) per 1000 live births in a year. MMR (Maternal Mortality Rate) is the number of maternal deaths per 1,00,000 live births. Population growth rate depends on births adding people and deaths removing them. A higher death rate of any group lowers the growth rate; a lower death rate of any group, on its own, does not add new people.

1. Increased IMR means more infants die. Fewer of the born children survive, so the surviving population grows more slowly. This pushes the growth rate down.
2. Decreased MMR means fewer mothers die. This protects mothers but does not by itself create extra births, so it has only a weak upward effect on growth, far smaller than the infant-death effect.
3. Combine the two. The strong downward push from increased IMR outweighs the weak effect of decreased MMR. The net result is a decline in the population growth rate.

Option (b): the growth rate declines.

Correct option: (a) Suppression of gonadotropins.

Concept used. Lactational amenorrhea is the absence of the menstrual cycle during the period a mother is intensely breast-feeding. Gonadotropins are FSH and LH, released by the anterior pituitary; they drive follicle growth and ovulation. Intense suckling raises blood prolactin, and prolactin suppresses the release of GnRH and hence of FSH and LH.

1. Intense and frequent suckling keeps blood prolactin high.
2. High prolactin suppresses the hypothalamic GnRH pulse, which in turn suppresses pituitary release of FSH and LH (the gonadotropins).
3. Without FSH and LH there is no follicle maturation and no ovulation. No ovum is released, so fertilisation and conception cannot occur (effective only up to about six months after childbirth).
4. Check the distractors: gametic transport (c) and fertilisation (d) never even begin because no ovum is produced, so the root cause is the suppression of gonadotropins, not these downstream steps. (b) is the opposite of what happens.

Option (a): high prolactin suppresses gonadotropins, so no ovulation.

Correct option: (d) i, ii, iii and iv.

Concept used. Sterilisation is a surgical contraceptive method: vasectomy in males (cutting/tying the vas deferens) and tubectomy in females (cutting/tying the fallopian tubes). It is highly reliable but is chosen last for several independent reasons; this is a "select all that apply" question, so we test each statement on its own.

1. Statement (i): sterilisation is almost irreversible; reversal surgery rarely restores fertility. This is a true reason couples hesitate. Accept (i).
2. Statement (ii): a widespread misconception that sterilisation lowers sexual urge or masculinity discourages people, even though it is biologically false. This is a real social barrier. Accept (ii).
3. Statement (iii): it is a surgical procedure, requiring an operation, anaesthesia and recovery, which many couples wish to avoid. Accept (iii).
4. Statement (iv): in many regions there is a lack of trained personnel and facilities, so the option is simply not easily available. Accept (iv).
5. All four statements are valid reasons, so the option listing all four is correct.

Option (d): i, ii, iii and iv are all valid reasons.

Correct option: (a) 1950s.

Concept used. India was among the first countries to launch a national programme to attain a totally reproductively healthy society. The original family planning programme was initiated in 1951, i.e. in the 1950s, and was later broadened and renamed Reproductive and Child Health Care (RCH).

1. Recall the NCERT statement: India initiated action plans and programmes at a national level "way back in 1951".
2. 1951 falls in the 1950s decade, so the matching option is (a).
3. Eliminate the rest: the 1960s, 1980s and 1990s are later decades; the start of the national approach was in the 1950s, even though the programme was strengthened in later decades.

Option (a): the 1950s (programme launched in 1951).

Correct option: (a) 72 hrs of coitus.

Concept used. Emergency contraceptives are methods (progestogen or progestogen+estrogen pills, or IUD insertion) used to avoid a possible pregnancy after unprotected coitus or a suspected contraceptive failure. They act mainly by delaying or stopping ovulation and by preventing fertilisation, so they must be used before fertilisation, not after pregnancy has begun.

1. The reference event is the act that could cause pregnancy, i.e. coitus (or rape / contraceptive failure).
2. These pills are effective if taken within about 72 hours of that coitus, so the time window is measured from coitus.
3. Eliminate the others: ovulation (b) is not directly known to the user; menstruation (c) is unrelated to the risk event; implantation (d) is too late, as a pregnancy may already be established.

Option (a): within 72 hours of coitus.

Correct option: (b) IUDs increase phagocytosis reaction in the uterus.

Concept used. Intra Uterine Devices (IUDs) are contraceptives placed inside the uterus by a doctor or trained nurse. They work by (i) increasing phagocytosis of sperms in the uterus, (ii) (copper IUDs) releasing Cu^2+ ions that suppress sperm motility and fertilising capacity, and (iii) (hormone IUDs) making the uterus unsuitable for implantation and the cervix hostile to sperms.

1. Test (a): IUDs are inserted by a doctor or expert nurse, not by the user herself. FALSE.
2. Test (b): IUDs increase the phagocytosis of sperms within the uterus. This is a stated mechanism. TRUE.
3. Test (c): IUDs do not stop gametogenesis (sperm and egg formation continue normally). FALSE.
4. Test (d): IUDs have a fixed effective life and must be replaced after that period. FALSE.
5. Only statement (b) is correct.

Option (b): IUDs increase phagocytosis of sperms in the uterus.

Correct option: (c) i and iv.

Concept used. Medical Termination of Pregnancy (MTP), also called induced abortion, is the intentional ending of a pregnancy before full term. In India it is legalised under specified conditions and regulated to avoid misuse, especially against female foeticide.

1. Statement (i): MTPs are relatively safe and generally advised in the first trimester (up to 12 weeks); later terminations are far riskier. TRUE.
2. Statement (ii): MTP is not a contraceptive. A contraceptive prevents pregnancy; MTP ends an already established pregnancy. FALSE.
3. Statement (iii): MTPs are not always surgical: early pregnancies can be terminated with drugs (non-surgical / medical MTP). FALSE.
4. Statement (iv): MTP must be performed by qualified medical personnel under regulated conditions. TRUE.
5. Accepted set =i, iv, which is option (c).

Option (c): statements i and iv are correct.

Correct option: (b) AIDS.

Concept used. Sexually Transmitted Diseases (STDs), or VD/RTI, spread mainly through sexual contact. Most produce local signs in the genital region, but AIDS (caused by HIV) attacks the body's immune system (helper T-lymphocytes) rather than the sex organs themselves.

1. Syphilis (a): bacterial STD producing genital sores (chancre). Affects sex organs.
2. Gonorrhea (c): bacterial STD causing genital discharge and inflammation. Affects sex organs.
3. Genital warts (d): caused by HPV, produces growths on the genitals. By definition affects sex organs.
4. AIDS (b): HIV destroys helper T-cells, crippling immunity throughout the body. The damage is systemic, not confined to the sex organs.
5. The odd one out is AIDS.

Option (b) AIDS: it damages the immune system, not the sex organs specifically.

Correct option: (d) All of the above.

Concept used. Condoms are barrier contraceptives made of thin rubber/latex that cover the penis (or vagina) so that the ejaculated semen does not enter the female reproductive tract. We test each listed reason for popularity.

1. Reason (a): the condom forms a physical barrier so sperms are not deposited in the vagina, preventing insemination. TRUE.
2. Reason (b): condoms are used only during coitus and do not require surgery, hormones or a device inside the body, so they do not interfere with the coital act and self-use gives privacy. TRUE.
3. Reason (c): by covering the genitals they prevent contact with body fluids, so they reduce the risk of STDs (including HIV). TRUE.
4. All three reasons are correct, so the combined option (d) is the answer.

Option (d): all three reasons are valid.

Correct option: (b) Zygote is collected from a female donor and transferred to the fallopian tube.

Concept used. ZIFT (Zygote Intra Fallopian Transfer) transfers a zygote or early embryo (up to the 8-blastomere stage) into the fallopian tube of a female who cannot otherwise conceive. Two facts fix the answer: the unit transferred is a zygote (not an ovum), and the destination is the fallopian tube (not the uterus).

1. Check the transferred unit. ZIFT moves a zygote / early embryo, not an ovum. This rules out (a) and (d), which transfer ova.
2. Check the destination. ZIFT delivers to the fallopian tube, not the uterus. This rules out (c), which goes to the uterus.
3. Only statement (b) has both correct: zygote → fallopian tube.

Option (b): zygote from a donor, transferred to the fallopian tube.

Correct option: (c) Vasectomy.

Concept used. A surgical contraceptive must block gamete transport while keeping the reproductive organs and hormones intact. Vasectomy (a small part of the vas deferens is cut and tied through a scrotal incision) does exactly this: sperms can no longer travel out, but the testes and hormone production are untouched. The other options remove organs and are therefore not contraceptive procedures.

1. Vasectomy (c): cuts/ties the vas deferens. Sperms are not delivered, but testosterone and the testes remain. This is a recognised sterilisation contraceptive. CORRECT.
2. Ovariectomy (a): surgical removal of the ovaries. This ends hormone production and is a treatment, not a contraceptive method.
3. Hysterectomy (b): surgical removal of the uterus, done for disease, not for contraception.
4. Castration (d): removal of the testes (or ovaries); it destroys reproductive and hormonal function and is not used as contraception.

Option (c) Vasectomy: blocks sperm transport while keeping organs and hormones intact.

Correct option: (c) ii and iii.

Concept used. Diaphragms are reusable barrier contraceptives made of rubber. They are inserted into the vagina to cover the cervix before coitus, forming a physical barrier that stops sperms from entering the uterus through the cervix.

1. Statement (i): diaphragms are placed in the vagina to cover the cervix, not introduced into the uterus (that describes an IUD). FALSE.
2. Statement (ii): they are placed to cover the cervical region. TRUE.
3. Statement (iii): they act as a physical barrier that blocks sperm entry through the cervix. TRUE.
4. Statement (iv): the diaphragm itself is not a spermicide; spermicidal creams/jellies are used along with it but are a separate agent. FALSE.
5. Accepted set =ii, iii, which is option (c).

Option (c): statements ii and iii are correct.

Concept used. Reproductive health is defined by the WHO as total well-being in all aspects of reproduction, that is, physical, emotional, behavioural and social well-being, not merely the proper working of the reproductive organs.

1. The statement is incomplete. Healthy reproductive functioning (normal organs, hormones and cycles) is only one part of reproductive health.
2. Reproductive health also includes freedom from STDs, awareness of safe sex, access to contraception, the right to unbiased counselling, and emotional and social well-being regarding reproduction.

False as stated: reproductive health means physical, emotional, behavioural and social well-being in reproduction, not just healthy organ function.

Concept used. The Reproductive and Child Health Care (RCH) programme is a Government of India initiative to create a reproductively healthy society through awareness, services and support, building on the earlier "family planning" programme of 1951.

1. Aims and tools: spread awareness via audio-visual and print media, schools and parents; provide sex education; build knowledge of reproductive organs, adolescence, safe sex, STDs and contraception.
2. Outcomes: it provides medical help and care to mothers and infants, encourages a smaller family through contraception, works to detect and discourage sex-selective abortion and child marriage, and improves overall reproductive health and lower mortality.

RCH is a national programme using awareness, education and medical services to build a reproductively healthy and informed society.

Concept used. Population growth rate is the rate at which a population increases, driven by a high birth rate relative to death rate. It is checked mainly by reducing the birth rate through education, delayed marriage and contraception.

1. Motivate smaller families: promote the small-family norm with statutory rise in marriageable age (21 for males, 18 for females) and incentives for couples with fewer children.
2. Spread awareness and access: sex education, counselling, and easy availability of contraceptive methods (barrier, IUD, pills, sterilisation) so that births are planned.

Raise marriage age, promote the small-family norm with incentives, and spread sex education plus easy contraceptive access.

Concept used. Sexually Transmitted Diseases (STDs) spread mainly through unprotected sexual contact. Most cases can be avoided by simple precautions, which is why they are called largely preventable, "self-invited" infections.

1. The phrase means most STDs arise from avoidable behaviour: unprotected sex, sex with unknown/multiple partners, and not using condoms.
2. They are preventable: avoid sex with unknown or multiple partners, always use condoms, and seek early diagnosis and treatment. Following these, infection is largely avoidable, hence "self-invited".

Largely true: most STDs result from avoidable unsafe sexual behaviour and can be prevented by safe practices.

Concept used. Sex education in schools gives correct information so that adolescents make informed, healthy choices and avoid myths.

1. Knowledge aspects: reproductive organs, adolescence and related changes, the menstrual cycle, and safe and hygienic sexual practices.
2. Protective aspects: STDs and AIDS and their prevention, myths/misconceptions about sex, available contraceptive options, and the evils of sex abuse and sex-selective practices.

Counsel on reproductive organs, adolescence, menstrual hygiene, safe sex, STDs/AIDS prevention, myths, contraception and sex abuse.

Concept used. Assisted Reproductive Technologies (ART) are special clinical techniques (IVF, ZIFT, GIFT, ICSI, artificial insemination, embryo transfer) that help couples who cannot conceive naturally because of infertility.

1. Many couples are infertile due to physical, congenital, immunological or other reasons and cannot produce a child by natural means.
2. The primary aim of the ART programme is to enable such infertile couples to have children by assisting fertilisation and/or implantation through medical techniques.

To help infertile couples have a child by using assisted clinical techniques to achieve pregnancy.

Concept used. The progesterone-estrogen combination (oral pills) is a hormonal contraceptive. The hormones act on the ovary and reproductive tract to stop pregnancy by three linked actions.

1. They inhibit ovulation by suppressing the release of the gonadotropins FSH and LH, so no ovum is released.
2. They alter the endometrium so it is unsuitable for implantation, and thicken cervical mucus to retard sperm entry. Together these make conception very unlikely.

It prevents ovulation, makes the endometrium unfit for implantation and thickens cervical mucus, so it is a highly effective contraceptive.

Concept used. Medical Termination of Pregnancy (MTP) is regulated by law in India to protect women's health and to prevent its misuse, particularly for illegal sex-selective abortion.

1. Reason 1: to prevent misuse: unregulated MTP is often used for illegal female foeticide after illegal sex determination. Strict conditions discourage this.
2. Reason 2: to protect the woman: MTPs (especially after the first trimester, or done by untrained persons) are unsafe and can be fatal, so they must be done by qualified personnel under defined limits.

(1) To stop misuse for illegal sex-selective abortion; (2) to protect the woman from unsafe, possibly fatal procedures.

Concept used. In males the testes normally descend into the scrotum, which is held at about 2 below core body temperature. Spermatogenesis (sperm formation) requires this lower temperature.

1. If the testes do not descend (a condition called cryptorchidism), they remain in the abdomen at full body temperature.
2. At this higher temperature normal spermatogenesis is impaired, so few or no functional sperms are produced. With no viable sperms, the male is generally infertile.

Undescended testes stay at body temperature, which prevents normal sperm formation, so the male is generally infertile.

Concept used. Lactational amenorrhea is the natural absence of menstruation (and ovulation) during the period of intense breast-feeding, up to about six months after childbirth.

1. Advantage 1: it is a natural method with no side effects: no drugs, devices or hormones are introduced into the body.
2. Advantage 2: it has no extra cost and needs no external aid; it works simply through the act of intense breast-feeding, which also benefits the infant.

(1) Natural, with no side effects; (2) free and needs no device or drug while breast-feeding.

Concept used. Improving reproductive health standards needs a combination of awareness, education, medical support and social reform, exactly the strategy of the RCH programme.

1. Awareness and education: use audio-visual and print media, schools and parents to give correct information on reproduction, adolescence, safe sex and STDs, and to remove myths.
2. Services and access: make a range of contraceptives freely available; provide care to pregnant mothers and infants; offer infertility help (ART).
3. Social reform: enforce the statutory marriage age, ban and detect sex-selective abortion, discourage child marriage, and provide unbiased counselling.

Spread awareness/sex education, ensure contraceptive access and maternal-child care, and enforce social reforms (marriage age, anti-foeticide laws).

Concept used. GIFT (Gamete Intra Fallopian Transfer) places the female gamete (ovum, from a donor) into the fallopian tube, because the fallopian tube (ampulla) is the natural site of fertilisation in humans.

1. Fertilisation in humans normally occurs in the ampullary region of the fallopian tube, not in the uterus. The early embryo then travels down and implants in the uterus.
2. GIFT therefore places the gamete where fertilisation can naturally take place, the fallopian tube.
3. If gametes were placed directly in the uterus, the environment is not suited to bring the gametes together for fertilisation, so the desired result (fertilisation → embryo) would not be achieved.
4. Hence gametes cannot simply be transferred to the uterus for GIFT; the fallopian tube is essential.

No. Fertilisation occurs in the fallopian tube, so gametes must go there; placing them in the uterus would not produce fertilisation.

Concept used. Intra Uterine Devices (IUDs) are of three types: non-medicated (e.g. Lippes loop), copper-releasing (e.g. CuT, Cu7, Multiload 375) and hormone-releasing (e.g. LNG-20). Copper IUDs add a chemical action to the physical action.

1. All IUDs increase phagocytosis of sperms in the uterus (physical/cellular action) and make the uterus unsuitable for implantation.
2. Copper IUDs additionally release Cu^2+ ions, which suppress sperm motility and the fertilising capacity of sperms.
3. Because copper IUDs combine the common phagocytic action with this extra spermicidal copper-ion action, fertilisation is far less likely, so they are more efficient than non-medicated IUDs.

Copper IUDs add the release of Cu^2+ ions that suppress sperm motility and fertilising capacity, on top of the usual IUD action, so they are more efficient.

Concept used. A population explosion is a sudden, steep rise in population size, caused when the birth rate stays high while the death rate falls sharply.

1. Fall in death rate: better health care reduced the Mortality Rate, the Maternal Mortality Rate (MMR) and the Infant Mortality Rate (IMR), so more people survived.
2. Rise in survivors of reproductive age: with more individuals surviving to reproductive age, more births occurred.
3. Social factors: high birth rate continued due to low literacy, early marriage, lack of awareness/availability of contraception and a preference for large families.

A sharp fall in death rate, MMR and IMR with continued high birth rate (early marriage, low awareness, more reproductive-age survivors) caused the explosion.

Concept used. IVF (In Vitro Fertilisation) is fertilisation outside the body (the "test-tube baby" programme). ET (Embryo Transfer) is the placement of the embryo formed by IVF into the female's body to continue development.

1. IVF: ova from the wife/donor and sperms from the husband/donor are collected and made to fuse in vitro (in the laboratory) to form a zygote.
2. ET: the resulting embryo is transferred to the female. If it has up to 8 blastomeres it is put into the fallopian tube (ZIFT); if it has more than 8 blastomeres it is put into the uterus (IUT), to complete development.
3. Conditions advised: when a couple is infertile, e.g. the female cannot produce ova, the male has very low sperm count, or there is a blockage/inability for natural fertilisation.

IVF = fertilisation in the lab; ET = transferring the resulting embryo to the fallopian tube (≤ 8 cells) or uterus (>8 cells). Advised for infertile couples (no ova, low sperm count, blocked tubes).

Concept used. Natural methods of contraception (periodic abstinence, withdrawal/coitus interruptus, lactational amenorrhea) work by avoiding the chance of the ovum and sperms meeting, without drugs or devices.

1. No side effects: they introduce no hormones, chemicals or foreign devices into the body, so there are no physiological side effects.
2. No cost and no aids: they need no purchase of pills, condoms or devices and require no surgery, only awareness of the fertile period and self-control.
3. They are ethically acceptable to people who object to artificial methods on personal or religious grounds.

Natural methods have no side effects, no cost, need no devices/surgery and are acceptable to those who reject artificial methods (but their failure rate is higher).

Concept used. Medical Termination of Pregnancy (MTP) is legally allowed only under specified medical and social conditions, mainly to safeguard the mother and in cases of unwanted or unsafe pregnancy.

1. When continuing the pregnancy would endanger the life or health of the mother (or cause grave physical/mental injury).
2. When the foetus is found to have serious abnormalities and would be severely handicapped.
3. When pregnancy results from rape or from failure of a contraceptive used by a married couple (unwanted pregnancy).

MTP is advised when the pregnancy risks the mother's life/health, when the foetus has serious abnormalities, or for pregnancy from rape or contraceptive failure.

Concept used. An ideal contraceptive is judged by how well it prevents pregnancy without harming the user or interfering with normal life and future fertility.

1. It should be user-friendly, easily available and effective (reliably prevents pregnancy).
2. It should have no or least side effects and should not interfere with the sexual act or the user's sexual drive.
3. It should be reversible, so that normal fertility returns when the couple wishes to have a child.

An ideal contraceptive is effective, user-friendly, reversible, with no/least side effects and no interference with sexual drive or the sexual act.

Concept used. Sexually Transmitted Diseases (STDs) are infections transmitted through sexual contact. Reproductive Tract Infections (RTIs) are the subset of STDs whose infection is localised in the reproductive tract / sex organs. Some STDs, however, spread beyond the reproductive tract.

1. RTIs are infections of the reproductive tract spread sexually, so by definition every RTI is also an STD. Example: gonorrhea and syphilis affect the genital tract: they are RTIs and STDs.
2. But some STDs are not confined to the reproductive tract: AIDS (HIV) attacks the immune system and Hepatitis-B affects the liver. They spread sexually but the disease is not localised in the reproductive tract.
3. Therefore all RTIs are STDs, but STDs like AIDS and Hepatitis-B are not RTIs.

Every RTI (e.g. gonorrhea, syphilis) is a sexually spread reproductive-tract infection, hence an STD; but STDs like AIDS and Hepatitis-B affect non-reproductive systems, so they are STDs that are not RTIs.

Concept used. Assisted Reproductive Technologies (ART) are special clinical methods used when a couple is infertile (cannot conceive naturally). The main techniques are IVF with ET, GIFT, ICSI, IUI and artificial insemination. Each assists either fertilisation or implantation. Below, three are described in full.

1. IVF with Embryo Transfer (ET) (the test-tube baby programme): ova from the wife (or a donor) and sperms from the husband (or a donor) are collected and induced to fuse in vitro to form a zygote. The embryo with up to 8 blastomeres is transferred into the fallopian tube (ZIFT); an embryo of more than 8 blastomeres is transferred into the uterus (IUT) to complete development. Advised when the female cannot conceive naturally despite normal gametes being available.
2. GIFT (Gamete Intra Fallopian Transfer): an ovum collected from a donor is transferred into the fallopian tube of a female who cannot produce ova but can provide a suitable environment for fertilisation and further development.
3. ICSI (Intra Cytoplasmic Sperm Injection): a single sperm is injected directly into the cytoplasm of the ovum in the laboratory to form the embryo. Used when the male has a very low sperm count or the sperms cannot fertilise the ovum on their own.
4. Related methods (named for completeness): Artificial Insemination (AI) / IUI, where semen from the husband or a donor is artificially introduced into the vagina or uterus, used when the male has very low sperm count or inability to inseminate.

ART includes IVF+ET, GIFT, ICSI, AI/IUI. IVF+ET: fertilise in vitro then transfer the embryo (tube if ≤ 8 cells, uterus if >8). GIFT: donor ovum into a recipient's fallopian tube. ICSI: one sperm injected straight into the ovum.

Concept used. Hormonal contraceptives use progestogens alone or with estrogen, given as oral pills, injectables or implants. They act on the ovary, the endometrium and the cervix to prevent pregnancy.

1. Mode of action: ovary: the hormones suppress the release of the gonadotropins FSH and LH from the pituitary, which inhibits ovulation, so no ovum is released.
2. Mode of action: endometrium: they alter the endometrium so that it becomes unsuitable for implantation of any embryo.
3. Mode of action: cervix: they make the cervical mucus thick, which retards the entry of sperms into the uterus.
4. Advantages: highly effective and reliable; do not interfere with the sexual act; reversible (fertility returns on stopping); also help regularise the menstrual cycle.
5. Disadvantages: must be taken regularly/on schedule (a missed pill lowers protection); may cause side effects in some women such as nausea, weight change, breakthrough bleeding or breast tenderness; do not protect against STDs.

Hormonal contraceptives block ovulation (suppress FSH/LH), make the endometrium unfit for implantation and thicken cervical mucus. Advantages: very effective, reversible, no coital interference. Disadvantages: strict schedule, possible side effects, no STD protection.

Concept used. Sexually Transmitted Diseases (STDs) spread mainly through unprotected sexual contact and damage reproductive health, sometimes fatally. We describe two and then list prevention.

1. AIDS (Acquired Immuno Deficiency Syndrome): caused by the HIV virus. HIV destroys helper T-lymphocytes, progressively crippling the immune system, so the patient suffers repeated infections. It spreads by unprotected sex, infected blood, shared needles and from infected mother to child. There is no complete cure, so it is largely fatal.
2. Gonorrhea: caused by the bacterium Neisseria gonorrhoeae. It produces inflammation, pain and discharge in the genital tract and, if untreated, can cause infertility (blocked tubes/ducts). It spreads through sexual contact and from mother to newborn.
3. Preventive measures: avoid sex with unknown or multiple partners; always use condoms during coitus; avoid shared needles and ensure blood is screened; get early diagnosis and complete treatment; spread awareness through education.

AIDS (HIV destroys immune T-cells, no cure) and Gonorrhea (bacterial genital infection causing infertility). Prevent by avoiding unknown/multiple partners, using condoms, safe blood/needles, and early treatment plus awareness.

Concept used. Amniocentesis is a prenatal test in which a sample of amniotic fluid is drawn and the foetal cells/chromosomes are analysed. It can detect genetic disorders and chromosomal abnormalities, but it also reveals the sex of the foetus.

1. Legitimate use: amniocentesis genuinely helps detect serious genetic disorders (e.g. Down's syndrome, haemophilia) and chromosomal/metabolic abnormalities before birth.
2. The problem: it also discloses the foetus's sex. In our society this has been widely misused for illegal female foeticide (selective abortion of female foetuses).
3. Consequence: large-scale female foeticide skews the sex ratio and is socially and ethically harmful.
4. Justification: yes, the statutory ban on amniocentesis for sex determination is justified, because the social harm of female foeticide outweighs convenience; it is allowed only for genuine medical diagnosis under regulation.

Yes, the ban (on its use for sex determination) is justified: amniocentesis was misused for illegal female foeticide, skewing the sex ratio; it is permitted only for genuine genetic diagnosis.

Concept used. Sex education in schools provides scientifically correct information about reproduction and sexuality so that adolescents grow up informed, safe and free of myths.

1. Correct knowledge of reproductive organs and adolescence: children learn the right facts about reproductive anatomy and the bodily and emotional changes of adolescence, reducing fear and confusion.
2. Removal of myths and misconceptions: it dispels false beliefs about sex, menstruation and reproduction that otherwise spread through unreliable sources.
3. Awareness of STDs and AIDS: it teaches how STDs (including AIDS) spread and how to prevent them, protecting future health.
4. Knowledge of safe sexual practices and contraception: it informs about responsible behaviour and available contraceptive options, helping prevent unwanted pregnancy.
5. Protection against sex abuse and sex-related crimes: it makes children aware of sexual abuse, helping them recognise, resist and report it, and discourages sex-selective practices.

Five reasons: (1) correct knowledge of reproductive organs/adolescence; (2) removal of myths; (3) awareness of STDs/AIDS; (4) safe-sex and contraception knowledge; (5) protection against sex abuse and crimes.