Sexual & Asexual Reproduction (AQA GCSE Biology: Combined Science)

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14 March 2024

Mitosis is a type of nuclear division that gives rise to cells that are genetically identical
It is used for growth, repair of damaged tissues, replacement of cells and asexual reproduction
Meiosis is a type of nuclear division that gives rise to cells that are genetically different
It is used to produce gametes (sex cells)

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Sexual reproduction is a process involving the fusion of the nuclei of two gametes (sex cells) to form a zygote (fertilised egg cell) and the production of offspring that are genetically different from each other
- The gametes of animals are the sperm cells and egg cells
- The gametes of flowering plants are the pollen cells and egg cells
Fertilisation is defined as the fusion of gamete nuclei, and as each gamete comes from a different parent, there is variation in the offspring
The formation of gametes involves meiosis

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Asexual reproduction does not involve sex cells or fertilisation
Only one parent is required so there is no fusion of gametes and no mixing of genetic information
As a result, the offspring are genetically identical to the parent and to each other (clones)
Asexual reproduction is defined as a process resulting in genetically identical offspring from one parent
Only mitosis is involved in asexual reproduction

the (exam) results speak for themselves:

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