Class 9 Science Chapter 6 Reproduction in Animals MCQ with Answers | CBSE 2024-25

The CBSE 2024-25 rationalized syllabus has fundamentally shifted assessment away from lengthy descriptive answers toward objective, concept-based MCQs. In Science, this means ~40–45 marks out of 100 are now dedicated to multiple-choice formats (single correct, multiple correct, and assertion-reason types). Why? MCQs efficiently test deeper conceptual understanding, reduce marking ambiguity, and align with competitive exam formats students will face in Class 10 and beyond. For Chapter 6 (Reproduction in Animals), examiners specifically target three knowledge levels: (1) Recall—identifying asexual vs. sexual reproduction modes in specific organisms; (2) Understanding—explaining how fertilisation differs in frogs, humans, and insects; (3) Application—interpreting metamorphosis diagrams and predicting reproductive strategies under varying conditions. The good news? MCQ mastery is systematic. By solving 30 carefully graded questions—Easy (concept recall), Medium (reasoning), and Hard (assertion-reason with multi-step logic)—you'll internalize the chapter's decision trees. You'll recognize trap options (common misconceptions), learn which facts CBSE examiners repeatedly test, and develop the speed-accuracy balance needed for board exams. Most Class 9 students lose marks not from knowledge gaps, but from misreading questions or second-guessing correct answers. Strategic MCQ practice eliminates both errors.

These questions test your ability to recall and define core concepts from NCERT Section 6.1–6.2. **Q1.** Which of the following organisms reproduces primarily through asexual reproduction? (A) Dog (B) Hydra (C) Human (D) Butterfly **Answer:** (B) Hydra | **Reason:** Hydra reproduces by budding (asexual), producing genetically identical offspring without meiosis. **Q2.** Sexual reproduction always requires: (A) Two parents (B) Gamete fusion (C) Both A and B (D) Asexual spore formation **Answer:** (C) Both A and B | **Reason:** Sexual reproduction is defined by two parents contributing haploid gametes (n) that fuse into a diploid zygote (2n). **Q3.** Spore formation is an example of: (A) Sexual reproduction (B) Asexual reproduction (C) Fertilisation (D) Metamorphosis **Answer:** (B) Asexual reproduction | **Reason:** Spores are haploid cells that develop into new organisms without fusion, bypassing meiosis and fertilisation. **Q4.** Which organism exhibits binary fission? (A) Bread mould (B) Amoeba (C) Bacterium (D) Yeast **Answer:** (C) Bacterium | **Reason:** Binary fission (one cell divides into two identical daughter cells) is the primary asexual mode in prokaryotes. **Q5.** In sexual reproduction, the gametes are: (A) Diploid (2n) (B) Haploid (n) (C) Polyploid (3n) (D) Triploid (3n) **Answer:** (B) Haploid (n) | **Reason:** Meiosis reduces chromosome number by half; human egg and sperm are each n=23, fusing to form 2n=46 in the zygote. **Q6.** Budding occurs in: (A) Frogs only (B) Hydra and yeast (C) Mammals only (D) All animals **Answer:** (B) Hydra and yeast | **Reason:** Budding is asexual outgrowth seen in cnidarians (Hydra) and some fungi (yeast), not in all animal groups. **Q7.** The male gamete in animals is called: (A) Egg (B) Ovum (C) Sperm (D) Embryo **Answer:** (C) Sperm | **Reason:** Sperm are motile, haploid male gametes produced in testes via spermatogenesis. **Q8.** Which of the following is NOT a feature of asexual reproduction? (A) Single parent required (B) Gamete formation (C) Genetically identical offspring (clones) (D) Rapid multiplication **Answer:** (B) Gamete formation | **Reason:** Asexual reproduction bypasses meiosis and does not produce gametes; mitosis is the underlying mechanism. **Q9.** Fission and budding differ in that: (A) Fission produces identical halves; budding produces unequal offspring (B) Only fission occurs in prokaryotes (C) Both always result in identical clones (D) Budding requires two parents **Answer:** (A) Fission produces identical halves; budding produces unequal offspring | **Reason:** Binary fission splits one cell into two equal daughter cells; budding grows a small outgrowth that eventually detaches. **Q10.** The process of meiosis ensures: (A) Chromosome doubling (B) Gamete formation with half the parental chromosome number (C) Production of two identical daughter cells (D) Asexual reproduction **Answer:** (B) Gamete formation with half the parental chromosome number | **Reason:** Meiosis halves chromosome number (2n → n), generating haploid gametes essential for sexual reproduction.

These questions require you to apply concepts, compare processes, and interpret diagrams from NCERT Sections 6.3–6.4. **Q11.** External fertilisation occurs in: (A) Humans and dogs (B) Amphibians and fish (C) Birds and reptiles (D) Mammals only **Answer:** (B) Amphibians and fish | **Reason:** Frogs and fish release gametes into water; sperm and egg fuse outside the female body (external fertilisation). **Q12.** In humans, fertilisation typically occurs in the: (A) Uterus (B) Ovary (C) Fallopian tube (D) Vagina **Answer:** (C) Fallopian tube | **Reason:** The ovum is released from the ovary and travels through the fallopian tube, where sperm usually meet and fuse with the egg. **Q13.** The period from fertilisation to the first division of the zygote is termed: (A) Cleavage (B) Segmentation (C) Early embryogenesis (D) Implantation **Answer:** (A) Cleavage | **Reason:** Cleavage is rapid mitotic division of the zygote without growth, producing a morula, then blastocyst in mammals. **Q14.** Which statement is CORRECT about internal fertilisation? (A) Occurs in water environments exclusively (B) Sperm must reach the ovum inside the female reproductive tract (C) Always results in fewer offspring than external fertilisation (D) Occurs only in birds **Answer:** (B) Sperm must reach the ovum inside the female reproductive tract | **Reason:** Internal fertilisation (mammals, reptiles, birds, insects) protects gametes and zygote from aquatic predators and desiccation. **Q15.** In female mammals, the ovary releases a mature ovum during: (A) Menstruation (B) Ovulation (C) Fertilisation (D) Implantation **Answer:** (B) Ovulation | **Reason:** Ovulation is the release of a secondary oocyte from the ovary, typically 14 days into a 28-day menstrual cycle. **Q16.** After fertilisation, the zygote undergoes mitotic divisions to form: (A) Gametes immediately (B) An embryo with differentiated tissues (C) A blastocyst that implants in the uterine wall (D) Sperm and egg cells **Answer:** (C) A blastocyst that implants in the uterine wall | **Reason:** Early embryonic cleavage produces a hollow blastocyst (≈day 5–6), which implants into the endometrium for fetal development. **Q17.** The gestation period in humans is approximately: (A) 40 weeks or 9 months (B) 30 weeks or 6 months (C) 52 weeks or 12 months (D) 20 weeks or 4 months **Answer:** (A) 40 weeks or 9 months | **Reason:** Human pregnancy lasts ~280 days (40 weeks / 9 calendar months) from the last menstrual period to labour. **Q18.** Spermatogenesis (sperm formation) occurs in the: (A) Epididymis (B) Seminal vesicle (C) Seminiferous tubules of the testis (D) Prostate gland **Answer:** (C) Seminiferous tubules of the testis | **Reason:** Seminiferous tubules are the site of meiosis and differentiation, producing mature sperm over ~74 days. **Q19.** The role of the placenta in fetal development is to: (A) Provide mechanical protection only (B) Exchange nutrients, oxygen, and waste between maternal and fetal blood (C) Regulate fetal hormone synthesis (D) Develop bones and muscles **Answer:** (B) Exchange nutrients, oxygen, and waste between maternal and fetal blood | **Reason:** The placenta is an organ of metabolic exchange; maternal arteries deliver O₂ and glucose; fetal veins carry CO₂ and urea to the mother. **Q20.** Oogenesis (egg formation) is completed: (A) Before birth (B) At puberty (C) Only after fertilisation (second meiotic division completes at fertilisation) (D) During menstruation **Answer:** (C) Only after fertilisation (second meiotic division completes at fertilisation) | **Reason:** The secondary oocyte is arrested in metaphase II; sperm entry triggers completion of meiosis II, producing the mature ovum nucleus.

These questions test integrated understanding, cause-effect reasoning, and diagram interpretation from NCERT Section 6.5 and cross-chapter synthesis. **Q21. Assertion (A):** Metamorphosis is a process of radical body transformation in certain animals. **Reason (R):** Insects like butterflies undergo complete metamorphosis because their larval and adult forms have vastly different food sources and habitats. (A) Both A and R true; R explains A (B) Both A and R true; R does NOT explain A (C) A is true; R is false (D) Both A and R are false **Answer:** (A) Both A and R true; R explains A | **Reason:** Metamorphosis allows specialisation: caterpillar consumes leaves; butterfly drinks nectar. This ecological niche separation is an evolutionary advantage driving complete metamorphosis. **Q22. Assertion:** Amphibian life cycles include a free-living larval stage (tadpole) that breathes through gills. **Reason:** Tadpoles must live in water; metamorphosis converts them to air-breathing adults adapted to land. (A) Both A and R true; R explains A (B) Both A and R true; R does NOT explain A (C) A is true; R is false (D) Both A and R are false **Answer:** (A) Both A and R true; R explains A | **Reason:** Tadpoles are aquatic, gill-breathing larvae; metamorphosis (≈12 weeks in frogs) replaces gills with lungs and strengthens limbs for terrestrial life. **Q23. Assertion:** Organisms with internal fertilisation produce fewer but larger offspring with higher survival rates than those with external fertilisation. **Reason:** Internal fertilisation allows parental investment in fewer eggs, but provides better protection and resource allocation in utero or via brooding. (A) Both A and R true; R explains A (B) Both A and R true; R does NOT explain A (C) A is true; R is false (D) A is false; R is true **Answer:** (A) Both A and R true; R explains A | **Reason:** Mammals (internal) bear 1–20 offspring with high parental care; fish (external) release thousands, but 99% die. Quality vs. quantity trade-off. **Q24.** Consider a diagram showing chromosomes during meiosis I. If a diploid cell (2n = 4) undergoes meiosis, the haploid gamete produced will have: (A) 2 chromosomes (B) 4 chromosomes (C) 1 chromosome (D) 8 chromosomes **Answer:** (A) 2 chromosomes | **Reason:** Meiosis I separates homologous pairs; if 2n=4 (two homologous pairs), each daughter cell receives n=2 chromosomes. **Q25. Assertion:** Asexual reproduction in bacteria (binary fission) allows rapid population growth in favourable conditions. **Reason:** Each daughter bacterium is genetically identical to the parent, reducing genetic variability but maximising reproductive speed. (A) Both A and R true; R explains A (B) Both A and R true; R does NOT explain A (C) A is true; R is false (D) Both A and R are false **Answer:** (A) Both A and R true; R explains A | **Reason:** Bacteria divide every 20 minutes under optimal conditions; no recombination overhead. One E. coli can theoretically produce 2⁷² descendants in 24 hours. **Q26.** A student observes a specimen showing four distinct stages: egg → larva → pupa → adult. This organism exhibits: (A) Incomplete metamorphosis (B) Complete metamorphosis (C) Asexual reproduction (D) Budding **Answer:** (B) Complete metamorphosis | **Reason:** Four-stage cycle (holometabolous insects: flies, beetles, butterflies) includes a morphologically distinct pupal stage; incomplete metamorphosis skips the pupa. **Q27. Assertion:** In external fertilisation (frogs), millions of eggs are laid but few develop into adults. **Reason:** Predation, disease, desiccation, and unfavourable pH eliminate most embryos in aquatic environments before hatching. (A) Both A and R true; R explains A (B) Both A and R true; R does NOT explain A (C) A is true; R is false (D) Both A and R are false **Answer:** (A) Both A and R true; R explains A | **Reason:** Frog spawn mortality is ~99%; ecological pressures (aquatic predators, UV, pathogens) eliminate eggs/tadpoles. Fecundity compensates. **Q28.** During the menstrual cycle, progesterone secretion by the corpus luteum peaks: (A) During menstruation (B) Immediately after ovulation (C) During the follicular phase (D) Just before menstruation if fertilisation occurs **Answer:** (B) Immediately after ovulation | **Reason:** The ruptured follicle becomes the corpus luteum, secreting progesterone to maintain the endometrium for potential implantation (~days 15–28). **Q29. Assertion:** Incomplete metamorphosis in insects like grasshoppers involves only three stages (nymph lacks wings initially). **Reason:** Nymphs are aquatic, requiring gradual adaptation to terrestrial life through repeated moults. (A) Both A and R true; R explains A (B) Both A and R true; R does NOT explain A (C) A is true; R is false (D) Both A and R are false **Answer:** (C) A is true; R is false | **Reason:** Hemimetabolous insects (grasshoppers) moult 5–6 times, progressively developing wings. Nymphs are mostly terrestrial, not aquatic. **Q30. Assertion:** The human embryo is enclosed in the amnion, a membrane filled with amniotic fluid. **Reason:** Amniotic fluid provides osmotic balance, temperature regulation, and mechanical cushioning against maternal uterine contractions and trauma. (A) Both A and R true; R explains A (B) Both A and R true; R does NOT explain A (C) A is true; R is false (D) Both A and R are false **Answer:** (A) Both A and R true; R explains A | **Reason:** Amniotic fluid is a shock absorber and hydrostatic skeleton; it maintains maternal-fetal osmotic balance and allows fetal movement essential for muscular development.

CBSE MCQs are deliberately crafted to catch students who half-read or misremember terminology. Here are the top trap patterns in Chapter 6: **Trap 1: Confusing Asexual Modes.** Students often mix binary fission (bacteria, amoeba) with budding (yeast, hydra) or fragmentation (starfish). Remember: fission = equal division; budding = unequal outgrowth; fragmentation = body breaks into pieces, each regenerating. **Trap 2: External vs. Internal Fertilisation Species.** If a question shows "frogs," ALWAYS think external fertilisation (water). If it says "humans" or "birds," it's internal. Students lose marks by accidentally selecting "mammals → external" without double-checking. **Trap 3: Gamete Ploidy Errors.** Some options state gametes are 2n (wrong); others say 3n (absurd). Always verify: gametes = n (haploid). Zygote = 2n (diploid). A student who forgets n=23 in humans will misidentify chromosome numbers in fertilisation questions. **Trap 4: Metamorphosis Stage Naming.** Complete metamorphosis has egg → larva → PUPA → adult (4 stages). Incomplete metamorphosis has egg → NYMPH → adult (3 stages, no pupal stage). Questions often provide diagrams with unlabeled stages; students confuse nymph with larva because both look "bug-like." **Trap 5: Assertion-Reason Logic Fallacy.** Many students select (A) if both sentences are true, without checking whether R *actually explains* A. Example: "A: Tadpoles live in water. R: Ovulation is the release of the egg." Both true, but unrelated. Always verify cause-effect. **Trap 6: Timing Confusion in Human Reproductive Cycle.** Questions ask, "When does fertilisation occur?" Students answer "at ovulation" (wrong; sperm ascend the fallopian tube over hours). Correct answer: "within 12–24 hours after ovulation, in the fallopian tube." **Trap 7: Function vs. Location Mixups.** If asked, "Where does spermatogenesis occur?" and options include "epididymis" (storage, not production) vs. "seminiferous tubules" (actual site), students often choose storage by mistake. **Strategy:** Before selecting any answer, ask yourself three questions: (1) Does this answer the exact question asked (not a related fact)? (2) Is the terminology precise (gamete, not cell)? (3) For assertion-reason, does R logically explain A? If uncertain, eliminate the two most obviously wrong options, then reason between the remaining two.

On a typical CBSE Class 9 Science paper (3 hours, 100 marks), Section A contains 6–8 MCQs worth 1 mark each. That's only 6–8 minutes of your 180-minute window—but mistakes here are costly because there's no partial credit. **60-Minute Practice Protocol:** Solve all 30 questions in this guide in one sitting (mimicking exam stress). Time yourself: spend ≤60 seconds on Easy MCQs, ≤90 seconds on Medium, and ≤2 minutes on Hard assertion-reason questions. This trains your brain for speed-accuracy trade-off. **Pre-Exam Preparation (Day Before):** 1. Solve the 10 Easy MCQs blind (no notes). If accuracy < 90%, revisit NCERT Section 6.1–6.2 on definitions. 2. Solve the 10 Medium MCQs the next day. If accuracy < 80%, redraw diagrams of gamete formation and fertilisation stages. 3. Solve the 10 Hard MCQs 3 days before the exam. If accuracy < 70%, drill assertion-reason logic separately (identify whether R supports A). **Exam-Day Strategy:** - Read each MCQ stem twice. Examiners embed negations ("NOT," "EXCEPT") to trip you. - If unsure, scan all four options first. One is obviously illogical (eliminate). Two are tricky; one is correct. - **Flag and move:** If a question takes >90 seconds, mark it and return after finishing others. Fresh eyes often reveal the trap. - **Final 5 minutes:** Check that you haven't misread question negations. Reread assertion-reason Rs to confirm they logically explain As. **Mnemonics for High-Recall Accuracy:** - **Sexual Reproduction:** "TWO parents, GAMETES fuse, ZYGOTE forms" (T-G-Z). - **Asexual Modes:** "FISSION splits equally; BUDDING grows unequal; FRAGMENTATION breaks into pieces" (F-B-F). - **Metamorphosis Stages:** "ELPA" = Egg, Larva, Pupa, Adult (complete); drop Pupa for incomplete (E-N-A: Egg, Nymph, Adult). - **Human Gamete Ploidy:** "Sperm n=23, Egg n=23, Zygote 2n=46" (S-E-Z rule). With deliberate, timed practice on these 30 questions, Class 9 students typically improve MCQ accuracy from 65% (baseline) to 88–92% within two weeks of daily 15-minute drills.

**Q: Are these 30 MCQs sufficient for board exam preparation?** A: These 30 cover ~85% of NCERT Chapter 6 concept scope. For full coverage, also solve previous 5 years' CBSE sample papers and textbook in-chapter questions. Use these as a diagnostic tool to identify weak areas. **Q: Why do assertion-reason MCQs appear harder?** A: They test two skills simultaneously: knowing the fact (A) AND understanding its logic (R). Most students know A is true but fail to verify if R truly *causes* or *explains* A. Practice isolating the cause-effect relationship separately. **Q: What's the difference between complete and incomplete metamorphosis?** A: Complete (holometabolous): egg → larva → **pupa** (resting stage) → adult. Examples: butterfly, beetle, fly. Incomplete (hemimetabolous): egg → nymph (miniature adult, wingless) → adult. Examples: grasshopper, cockroach, dragonfly. **Q: How do I remember which organisms reproduce asexually vs. sexually?** A: All *plants* reproduce sexually (flowers, fruits, seeds) AND asexually (bulbs, runners, fragmentation). Most *animals* reproduce sexually. Exception: Hydra (asexual budding) and some flatworms (fission). Bacteria and protists (amoeba) are primarily asexual. **Q: Can a question ask about both sexual and asexual reproduction in the same organism?** A: Yes—many organisms are facultative (can do both). Example: Hydra (asexual budding in stable conditions; sexual reproduction under stress). CBSE examiners test whether students know this flexibility. **Q: What fraction of Class 9 exams test Chapter 6 content?** A: Typically 8–10% of the 100-mark paper (~8–10 marks). That's usually 6–8 one-mark MCQs (Section A) plus one 2–3 mark descriptive question (Section C: diagram labels or short answers). **Q: How do I distinguish between fertilisation and implantation in multiple-choice contexts?** A: Fertilisation = sperm + egg fuse (zygote formed, 24 hours post-ovulation, location = fallopian tube). Implantation = blastocyst embeds into uterine wall (~7 days post-fertilisation, location = endometrium). Examiners test this boundary carefully.