Question
Some descriptions of reproduction are listed.
- formation of a zygote with a diploid nucleus
- formation of a zygote with a haploid nucleus
- fusion of diploid nuclei of two gametes
- fusion of haploid nuclei of two gametes
Which are correct descriptions of sexual reproduction in humans?
▶️ Answer/Explanation
Solution
Ans: B
In human sexual reproduction, haploid gametes (sperm and egg) fuse to form a diploid zygote (1 correct). The fusion is of haploid nuclei (4 correct), not diploid nuclei. Therefore, the correct combination is 1 and 4.
Question
What is a disadvantage of sexual reproduction for a population in the wild?
▶️ Answer/Explanation
Solution
Ans: C
Sexual reproduction requires mates, so isolated individuals cannot reproduce (C). Options A/B/D are incorrect because sexual reproduction actually increases genetic diversity and adaptability. The real disadvantage is the need for a partner, making C the correct answer.