Bio Zoology · Chapter 3

Samacheer Class 12 Bio Zoology - Reproductive Health

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Q.1 Which of the following is correct regarding HIV, hepatitis B, gonorrhoea and trichomoniasis? (a) Gonorrhoea is a STD whereas others are not. (b) Trichomoniasis is a viral disease whereas others are bacterial. (c) HIV is a pathogen whereas others are diseases. (d) Hepatitis B is eradicated completely whereas others are not.
Answer: c

HIV (Human Immunodeficiency Virus) names a pathogen (a virus). The other terms as written (hepatitis B, gonorrhoea, trichomoniasis) commonly refer to the diseases/clinical conditions caused by agents. (Note: hepatitis B is caused by HBV, a virus; gonorrhoea by Neisseria gonorrhoeae (bacterium); trichomoniasis by Trichomonas vaginalis (protozoan).)

Q.2 Which one of the following groups includes sexually transmitted diseases caused by bacteria only? (a) Syphilis, gonorrhoea and candidiasis (b) Syphilis, chlamydiasis and gonorrhoea (c) Syphilis, gonorrhoea and trichomoniasis (d) Syphilis, trichomoniasis and pediculosis
Answer: b

Syphilis (Treponema pallidum), chlamydiasis (Chlamydia trachomatis) and gonorrhoea (Neisseria gonorrhoeae) are all caused by bacteria. Candidiasis is fungal and trichomoniasis is protozoan.

Q.3 Identify the correct statements from the following (a) Chlamydiasis is a viral disease. (b) Gonorrhoea is caused by a spirochaete bacterium, Treponema palladium. (c) The incubation period for syphilis is 2 to 14 days in males and 7 to 21 days in females. (d) Both syphilis and gonorrhoea are easily cured with antibiotics.
Answer: d

a is false (chlamydiasis is bacterial — Chlamydia trachomatis). b is false (Treponema pallidum causes syphilis; gonorrhoea is caused by Neisseria gonorrhoeae). c is incorrect as stated (incubation periods differ; syphilis incubation usually 10–90 days). d is correct in principle: syphilis and gonorrhoea are bacterial infections and are treatable with appropriate antibiotics (though antibiotic resistance and treatment failures can complicate therapy).

Q.4 A contraceptive pill prevents ovulation by (a) blocking fallopian tube (b) inhibiting release of FSH and LH (c) stimulating release of FSH and LH (d) causing immediate degeneration of released ovum
Answer: b

Combined hormonal contraceptives provide negative feedback on the hypothalamic–pituitary axis, suppressing release of FSH and LH and thereby preventing follicular development and ovulation.

Q.5 The approach which does not give the defined action of contraceptive is (a) Hormonal Prevents entry of sperms, contraceptive prevent ovulation and fertilization (b) Vasectomy Prevents spermatogenesis (c) Barrier Prevents fertilization method (d) Intra uterine Increases phagocytosis of device sperms, suppresses sperm motility and fertilizing capacity of sperms
Answer: b

Vasectomy blocks transport of sperm by cutting/ligating the vas deferens but does not stop spermatogenesis. Sperm production in the testes continues; sperm are resorbed. Thus the stated action 'prevents spermatogenesis' is incorrect.

Q.6 Read the given statements and select the correct option. Statement 1: Diaphragms, cervical caps and vaults are made of rubber and are inserted into the female reproductive tract to cover the cervix before coitus. Statement 2: They are chemical barriers of conception and are reusable. (a) Both statements 1 and 2 are correct and statement 2 is the correct explanation of statement 1. (b) Both statements 1 and 2 are correct but statement 2 is not the correct explanation of statement 1. (c) Statement 1 is correct but statement 2 is incorrect. (d) Both statements 1 and 2 are incorrect.
Answer: c

Statement 1 is correct — diaphragms, cervical caps and vaults are rubber devices placed over the cervix (mechanical barrier). Statement 2 is incorrect because these are mechanical barrier methods (not chemical), though they may be used with spermicidal creams; they are generally reusable.

Q.7 Match column I with column II and select the correct option from the codes given below. Column I Column II A. Copper releasing IUD (i) LNG-20 B. Hormone releasing (ii) Lippes loop IUD C. Non medicated IUD (iii) Saheli D. Mini pills (iv) Multiload-375 (a) A-(iv), B-(ii), C-(i), D-(iii) (b) A-(iv), B-(i), C-(iii), D-(ii) (c) A-(i), B-(iv), C-(ii), D-(iii) (d) A-(iv), B-(i), C-(ii), D-(iii)
Answer: d

Correct matching: A (Copper releasing IUD) — Multiload-375 (iv); B (Hormone releasing) — LNG-20 (i); C (Non-medicated IUD) — Lippes loop IUD (ii); D (Mini pills) — Saheli (iii).

Q.8 Select the incorrect action of hormonal contraceptive pills from the following (a) Inhibition of spermatogenesis. (b) Inhibition of ovulation. (c) Changes in cervical mucus impairing its ability to allow passage and transport of sperms. (d) Alteration in uterine endometrium to make it unsuitable for implantation.
Answer: a

Hormonal contraceptive pills act mainly in the female: they inhibit ovulation (through suppression of FSH/LH), thicken cervical mucus and alter endometrium. They do not inhibit spermatogenesis (that occurs in males).

Q.9Select the correct term from the bracket and complete the given branching tree Birth control methods Condoms, vaults, Caps etc., Pills Vasectomy B Coitus interruptus Periodic abstinence Natural methods A Oral contraceptives Surgical methods IUDs (Barriers, Lactational amenorrhoea, CuT, Tubectomy) 44 Reprod u c t i v e Health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v

Answer:

  • A — Barriers (e.g., condoms, caps, vaults)
  • B — Lactational amenorrhoea (natural method)
  • C — CuT (IUD)
  • D — Tubectomy (surgical method)
Q.10Correct the following statements a) Transfer of an ovum collected from donor into the fallopian tube is called ZIFT. b) Transfering of an embryo with more than 8 blastomeres into uterus is called GIFT. c) Multiload 375 is a hormone releasing IUD.v
Solution

Corrections: a) ZIFT (Zygote Intrafallopian Transfer) is transfer of a fertilized ovum (zygote) into the fallopian tube. Transfer of unfertilized ova and sperms into the fallopian tube is GIFT (Gamete Intrafallopian Transfer). b) Transfer of an embryo (more than 8 blastomeres) into the uterus is called embryo transfer (ET) — not GIFT. c) Multiload-375 is a copper releasing IUD (a Cu‑IUD), not a hormone releasing IUD.

Answer:

Corrections: a) ZIFT (Zygote Intrafallopian Transfer) is transfer of a fertilized ovum (zygote) into the fallopian tube. Transfer of unfertilized ova and sperms into the fallopian tube is GIFT (Gamete Intrafallopian Transfer). b) Transfer of an embryo (more than 8 blastomeres) into the uterus is called embryo transfer (ET) — not GIFT. c) Multiload-375 is a copper releasing IUD (a Cu‑IUD), not a hormone releasing IUD.

Q.11Which method do you suggest the couple to have a baby, if the male partner fails to inseminate the female or due to very low sperm count in the ejaculate?v
Solution

Recommend assisted reproductive techniques such as ICSI (Intracytoplasmic Sperm Injection) as part of IVF — a single sperm is injected directly into the oocyte, suitable for very low sperm count or failure to inseminate. Alternatives: donor insemination or IUI if adequate motile sperm are available.

Answer:

Recommend assisted reproductive techniques such as ICSI (Intracytoplasmic Sperm Injection) as part of IVF — a single sperm is injected directly into the oocyte, suitable for very low sperm count or failure to inseminate. Alternatives: donor insemination or IUI if adequate motile sperm are available.

Q.12Expand the following a) ZIFT b) ICSIv
Solution

a) ZIFT — Zygote Intrafallopian Transfer. b) ICSI — Intracytoplasmic Sperm Injection.

Answer:

a) ZIFT — Zygote Intrafallopian Transfer. b) ICSI — Intracytoplasmic Sperm Injection.

Q.13What are the strategies to be implemented in India to attain total reproductive health?v
Solution

Key strategies: 1) Comprehensive sex education and awareness programmes about contraception, STDs and reproductive rights. 2) Universal access to family planning services and a range of contraceptive options (barrier, hormonal, IUDs, permanent methods). 3) Strengthening maternal health services: antenatal care, skilled birth attendants, emergency obstetric care and postnatal care. 4) Prevention and treatment of STDs/HIV: screening, condoms, vaccination (HBV, HPV), timely treatment and partner notification. 5) Safe and legal abortion services with counselling. 6) Regulation and enforcement to prevent sex‑selective practices and foeticide, and promotion of gender equity. 7) Adolescent reproductive health services and counseling. 8) Improved access in rural/remote areas, training of health workers and ensuring affordability.

Answer:

Key strategies: 1) Comprehensive sex education and awareness programmes about contraception, STDs and reproductive rights. 2) Universal access to family planning services and a range of contraceptive options (barrier, hormonal, IUDs, permanent methods). 3) Strengthening maternal health services: antenatal care, skilled birth attendants, emergency obstetric care and postnatal care. 4) Prevention and treatment of STDs/HIV: screening, condoms, vaccination (HBV, HPV), timely treatment and partner notification. 5) Safe and legal abortion services with counselling. 6) Regulation and enforcement to prevent sex‑selective practices and foeticide, and promotion of gender equity. 7) Adolescent reproductive health services and counseling. 8) Improved access in rural/remote areas, training of health workers and ensuring affordability.

Q.14Differentiate foeticide and infanticide.v
Solution

Foeticide: deliberate killing of a fetus before birth (often by abortion); occurs during pregnancy, frequently connected with prenatal sex‑selection. Infanticide: killing of a newborn baby after birth. Differences: timing (prenatal vs postnatal), legal/ethical framing (both are criminal/illegal in most jurisdictions), methods (abortion/medical termination vs direct killing), and social causes (sex bias, poverty, stigma).

Answer:

Foeticide: deliberate killing of a fetus before birth (often by abortion); occurs during pregnancy, frequently connected with prenatal sex‑selection. Infanticide: killing of a newborn baby after birth. Differences: timing (prenatal vs postnatal), legal/ethical framing (both are criminal/illegal in most jurisdictions), methods (abortion/medical termination vs direct killing), and social causes (sex bias, poverty, stigma).

Q.15Describe the major STDs and their symptoms.v
Solution

Major STDs and typical symptoms: - Syphilis (Treponema pallidum): primary chancre (painless ulcer), secondary rash and mucous lesions, later latent/tertiary systemic disease. - Gonorrhoea (Neisseria gonorrhoeae): purulent urethral/vaginal discharge, dysuria; can cause pelvic inflammatory disease (PID) in females and infertility. - Chlamydiasis (Chlamydia trachomatis): often asymptomatic; may cause urethritis, cervicitis, PID, infertility. - Genital herpes (Herpes simplex virus HSV‑2/HSV‑1): painful vesicles and ulcers on genitals, recurrent episodes. - Human papillomavirus (HPV): genital warts (condylomata); some strains associated with cervical cancer. - Trichomoniasis (Trichomonas vaginalis): frothy, foul-smelling vaginal discharge, itching, dysuria. - HIV/AIDS (Human Immunodeficiency Virus): initial flu-like illness; progressive immunodeficiency leading to opportunistic infections. - Hepatitis B (HBV): jaundice, malaise, liver dysfunction; transmitted sexually and by blood. Note: many STDs may be asymptomatic, especially in women, yet cause long-term complications (infertility, cancer, systemic disease).

Answer:

Major STDs and typical symptoms: - Syphilis (Treponema pallidum): primary chancre (painless ulcer), secondary rash and mucous lesions, later latent/tertiary systemic disease. - Gonorrhoea (Neisseria gonorrhoeae): purulent urethral/vaginal discharge, dysuria; can cause pelvic inflammatory disease (PID) in females and infertility. - Chlamydiasis (Chlamydia trachomatis): often asymptomatic; may cause urethritis, cervicitis, PID, infertility. - Genital herpes (Herpes simplex virus HSV‑2/HSV‑1): painful vesicles and ulcers on genitals, recurrent episodes. - Human papillomavirus (HPV): genital warts (condylomata); some strains associated with cervical cancer. - Trichomoniasis (Trichomonas vaginalis): frothy, foul-smelling vaginal discharge, itching, dysuria. - HIV/AIDS (Human Immunodeficiency Virus): initial flu-like illness; progressive immunodeficiency leading to opportunistic infections. - Hepatitis B (HBV): jaundice, malaise, liver dysfunction; transmitted sexually and by blood. Note: many STDs may be asymptomatic, especially in women, yet cause long-term complications (infertility, cancer, systemic disease).

Q.16How are STDs transmitted?v
Solution

Modes of transmission: sexual contact (vaginal, anal, oral), vertical transmission (mother to child during pregnancy, childbirth or breastfeeding), blood-borne routes (transfusions, contaminated needles), and sharing of contaminated instruments. Intimate skin-to-skin contact can transmit some infections (e.g., HPV, herpes).

Answer:

Modes of transmission: sexual contact (vaginal, anal, oral), vertical transmission (mother to child during pregnancy, childbirth or breastfeeding), blood-borne routes (transfusions, contaminated needles), and sharing of contaminated instruments. Intimate skin-to-skin contact can transmit some infections (e.g., HPV, herpes).

Q.17Write the preventive measures of STDs.v
Solution

Prevention: consistent and correct use of condoms, mutual monogamy with uninfected partner or abstinence, vaccination (HBV, HPV), routine screening and early treatment of infected persons, safe blood transfusion and sterile needles, education and counselling, partner notification and treatment, and safe childbirth practices to prevent vertical transmission.

Answer:

Prevention: consistent and correct use of condoms, mutual monogamy with uninfected partner or abstinence, vaccination (HBV, HPV), routine screening and early treatment of infected persons, safe blood transfusion and sterile needles, education and counselling, partner notification and treatment, and safe childbirth practices to prevent vertical transmission.

Q.18The procedure of GIFT involves the transfer of female gametes into the fallopain tube, can gametes be transferred to the uterus to achieve the same result? Explain.v
Solution

No — GIFT (Gamete Intrafallopian Transfer) places eggs and sperm into the fallopian tube because fertilization normally occurs there; bringing gametes together in the tube allows natural fertilization. Transferring unfertilized gametes into the uterus would not ensure meeting and fertilization (uterus is the site for implantation of an embryo after fertilization). Embryo transfer (ET) places already fertilized embryos into the uterus, which is appropriate for implantation, but transferring gametes to the uterus is not an effective substitute for GIFT.

Answer:

No — GIFT (Gamete Intrafallopian Transfer) places eggs and sperm into the fallopian tube because fertilization normally occurs there; bringing gametes together in the tube allows natural fertilization. Transferring unfertilized gametes into the uterus would not ensure meeting and fertilization (uterus is the site for implantation of an embryo after fertilization). Embryo transfer (ET) places already fertilized embryos into the uterus, which is appropriate for implantation, but transferring gametes to the uterus is not an effective substitute for GIFT.

Q.19Amniocentesis, the foetal sex determination test, is banned in our country, Is it necessary? Comment.v
Solution

Yes — bans on prenatal sex determination (using amniocentesis/ultrasound for sexing) are necessary to prevent sex‑selective abortions and female foeticide, which cause severe demographic and social harm. Clinically, amniocentesis is an important diagnostic tool for genetic disorders and fetal karyotyping and should be used only for valid medical indications under strict regulation. Thus banning sex‑determination while permitting medically justified use with safeguards is the appropriate policy.

Answer:

Yes — bans on prenatal sex determination (using amniocentesis/ultrasound for sexing) are necessary to prevent sex‑selective abortions and female foeticide, which cause severe demographic and social harm. Clinically, amniocentesis is an important diagnostic tool for genetic disorders and fetal karyotyping and should be used only for valid medical indications under strict regulation. Thus banning sex‑determination while permitting medically justified use with safeguards is the appropriate policy.

Q.20Explain the various barrier methods to control human population.v
Solution

Barrier methods physically prevent sperm from reaching the ovum. Major barrier methods: - Male condom: thin sheath worn over the penis; prevents semen entering the vagina and reduces risk of STDs. - Female (internal) condom: pouch inserted into the vagina; protects against pregnancy and some STDs. - Diaphragm: dome-shaped rubber cup placed over the cervix before intercourse; usually used with spermicidal gel. - Cervical cap: smaller cap fitted over the cervix; used with spermicide. - Vaginal sponge/contraceptive vault: sponge containing spermicide placed over cervix. - Spermicidal creams, gels, foams and suppositories: chemical agents that immobilize/kill sperm; often used with mechanical barriers. Advantages: non‑hormonal, reversible, immediate effect, condoms protect against STDs. Limitations: user-dependent effectiveness, possible allergic reactions (latex), less effective than some hormonal/IUD methods when used imperfectly. Correct and consistent use improves effectiveness.

Answer:

Barrier methods physically prevent sperm from reaching the ovum. Major barrier methods: - Male condom: thin sheath worn over the penis; prevents semen entering the vagina and reduces risk of STDs. - Female (internal) condom: pouch inserted into the vagina; protects against pregnancy and some STDs. - Diaphragm: dome-shaped rubber cup placed over the cervix before intercourse; usually used with spermicidal gel. - Cervical cap: smaller cap fitted over the cervix; used with spermicide. - Vaginal sponge/contraceptive vault: sponge containing spermicide placed over cervix. - Spermicidal creams, gels, foams and suppositories: chemical agents that immobilize/kill sperm; often used with mechanical barriers. Advantages: non‑hormonal, reversible, immediate effect, condoms protect against STDs. Limitations: user-dependent effectiveness, possible allergic reactions (latex), less effective than some hormonal/IUD methods when used imperfectly. Correct and consistent use improves effectiveness.

Q.21Open Book Assessment: 'Healthy reproduction, legally checked birth control measures and proper family planning programmes are essential for the survival of mankind.' Justify.v
Solution

Justification (concise, textbook-style): 1. Population control and carrying capacity: Uncontrolled population growth leads to overpopulation, exceeding the Earth's carrying capacity and causing scarcity of food, water and shelter. Family planning and contraception (condoms, oral contraceptives, IUDs, sterilization) help achieve replacement-level fertility and prevent population explosion. 2. Maternal and child health (reproductive health): Healthy reproduction — including antenatal care, skilled birth attendance, postnatal care, immunization and nutrition — reduces maternal mortality, neonatal and infant mortality and prevents complications of pregnancy and childbirth. 3. Prevention of unwanted pregnancies and unsafe abortion: Access to legally checked birth control and safe abortion services reduces unsafe abortions and associated maternal deaths; legal regulation ensures quality, informed consent and protection of reproductive rights. 4. Disease prevention: Family planning and reproductive health services include screening and prevention of sexually transmitted infections (STIs) including HIV, improving overall public health. 5. Socioeconomic benefits: Smaller, planned families enable better allocation of household and national resources, improve education and employment opportunities (especially for women), reduce poverty and accelerate economic development. 6. Environmental sustainability: Slower population growth lessens pressure on natural resources, reduces habitat destruction and pollution, aiding long-term survival of humans and biodiversity. 7. Ethical and legal safeguards: Legally checked measures prevent coercive or unsafe practices (e.g., forced sterilization), ensure informed choice and protect human rights. Conclusion: Integrated reproductive health services, legally regulated contraception and comprehensive family planning are indispensable for safeguarding health, securing resources, achieving sustainable development and thereby ensuring the survival and well‑being of mankind.

Answer:

Healthy reproduction, legally regulated birth control and effective family planning ensure sustainable population levels, protect maternal and child health, preserve resources and environment, and promote socioeconomic development — all essential for mankind's survival.