During which process does fertilisation restore the diploid chromosome number in sexually reproducing organisms?

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Question

During which process does fertilisation restore the diploid chromosome number in sexually reproducing organisms?

Accepted Answer

When two haploid gametes fuse together — Fertilisation involves the fusion of two haploid gametes (each with half the chromosome number), restoring the full diploid number in the zygote. Option B describes mitosis, which does not restore the diploid number after reduction. Option C describes DNA replication, which does not change chromosome number. Option D describes division of a haploid cell, which keeps the number halved.

Answer

When a diploid cell undergoes mitotic division

Answer

When a haploid cell divides to produce two haploid cells

Answer

When chromosomes replicate prior to cell division

Answer

When two haploid gametes fuse together

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