Every Book Back multiple-choice question from Reproduction in Organisms (12th Standard Zoology, Samacheer Kalvi) — each with the correct option highlighted and a clear, worked explanation. Free to read in English and Tamil.
Q1
In which type of parthenogenesis are only males produced?
- A. ArrhenotokyCorrect
- B. Thelytoky
- C. Amphitoky
- D. Both a and b
Explanation. Arrhenotoky is a form of natural parthenogenesis where unfertilized eggs develop exclusively into male offspring, as seen in honeybees.
Q2
The mode of sexual reproduction in bacteria is by
- A. Formation of gametes
- B. Endospore formation
- C. ConjugationCorrect
- D. Zoospore formation
Explanation. In bacteria, conjugation is a process of genetic transfer that serves as a primitive form of sexual reproduction where nuclear material is exchanged between two cells.
Q3
In which mode of reproduction variations are seen
- A. Asexual
- B. Parthenogenesis
- C. SexualCorrect
- D. Both a and b
Explanation. Sexual reproduction involves the fusion of male and female gametes from two parents, leading to genetic recombination and variations in the offspring.
Q4
Assertion: In bee society, all the members are diploid except drones.
Reason: Drones are produced by parthenogenesis.
- A. If both A and R are true and R is correct explanation for ACorrect
- B. If both A and R are true but R is not the correct explanation for A
- C. If A is true but R is false
- D. If both A and R are false
Explanation. In honeybees, females are diploid while males are haploid because they develop from unfertilized eggs via parthenogenesis, which explains the ploidy exception.
About these Reproduction in Organisms questions
These are the Book Back multiple-choice questions for Reproduction in Organisms from the Tamil Nadu State Board (Samacheer Kalvi) 12th Standard Zoology syllabus. Each question shows the correct option and an original, step-by-step explanation so you understand the method, not just the answer. Use the answer key above to jump to any question, then take the practice test to check yourself under exam-like conditions.
Frequently asked questions
How many MCQs are there in Reproduction in Organisms?
This chapter has 4 book-back multiple-choice questions, each with the correct answer and a step-by-step explanation.
Are these 12th Standard Zoology MCQs free to practise online?
Yes. Every question, answer and explanation here is free, and you can also take them as a timed practice test.
Where can I find the Reproduction in Organisms book-back answers?
The correct option for each question is highlighted on this page with a worked explanation, plus a quick answer-key summary at the top.
