Question

Fertilisation is defined as the process by which

• A. a diploid spermatozoan unites with a haploid ovum to form a triploid zygote
• B. a haploid spermatozoan unites with a haploid ovum to form a diploid zygote
• C. a diploid spermatozoan unites with a diploid ovum to form a diploid zygote
• D. a diploid spermatozoan unites with a haploid ovum to form a diploid zygote.

Answer 1

Answer: (B)

a haploid spermatozoan unites with a haploid ovum to form a diploid zygote

The germ cells or gametes have half the number of chromosomes of the original organism. The haploid ('n' or half number of chromosomes) male germ cell or spermatozoan and female germ cell or ovum fuse together by the process of fusion or fertilization to give rise to a diploid zygote ('2n' or having the whole set of chromosomes). This is a form of sexual reproduction and involves the mating between the male and the female to result in this process of fusion.

So, the correct answer is 'a haploid spermatozoan unites with a haploid ovum to form a diploid zygote'.