IGCSE Biology glossary
Sexual reproduction
Biology editorial review is supported by the named review panel. Reviewer participation may vary by guide. Checked against Cambridge IGCSE Biology 0610 (2026–2028); last reviewed August 2026.
Definition
A process involving the fusion of the nuclei of two gametes (sex cells) to form a zygote and the production of offspring that are genetically different from each other.
What to include in an exam answer
Examiners pay for 'fusion of nuclei of two gametes' and for the genetic variation it produces. A common error is writing 'fusion of two gametes' without 'nuclei', or forgetting that gametes are haploid so the zygote is diploid. The variation point is what links this to survival in changing environments and is often the explain mark in Paper 4.
Example in context
Defining the term: 'Sexual reproduction involves the fusion of the nuclei of two haploid gametes to form a diploid zygote, producing offspring that show genetic variation.'
Related syllabus topic
Reproduction