Sexual & Asexual Reproduction (AQA GCSE Biology): Revision Note

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)

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

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