Sexual & Asexual Reproduction: Differences (Edexcel IGCSE Science)

Sexual Reproduction

Spec point — 4.1 · understand the differences between sexual and asexual reproduction

• Sexual reproduction is the production of offspring by the fusion of male and female gametes
• Offspring inherit genetic material from both parents, making them genetically different from either parent
• Sexual reproduction requires two parents, and only special cells called gametes are involved
• Gametes are produced through meiosis, a type of cell division that halves the chromosome number
• Fertilisation of a male and female gamete produces a zygote, which divides by mitosis (a different type of cell division to meiosis) and develops into an embryo
• Because offspring are genetically different from their parents, sexual reproduction introduces variation into populations

Asexual Reproduction

Spec point — 4.1 · understand the differences between sexual and asexual reproduction

• Asexual reproduction is the production of offspring from a single parent
• Asexual reproduction does not involve gametes or fertilisation
• Only one parent cell 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 (they are clones)
• The process occurs much more quickly and efficiently than sexual reproduction which can provide a survival advantage to populations
• However, lack of genetic variation means that populations are more vulnerable to disease or environmental change
• Many plants reproduce via asexual reproduction

Comparing Sexual & Asexual Reproduction

Spec point — 4.1 · understand the differences between sexual and asexual reproduction

• The key differences between sexual and asexual reproduction are compared in this table below: