Asexual reproduction is the production of new individuals from a single parent, without the fusion of gametes. In eukaryotes the new cells are produced by mitosis (bacteria use binary fission), so the offspring are genetically identical to the parent and to each other. A group of genetically identical organisms is called a clone.The only source of genetic variation between asexually produced offspring is mutation. There is no meiosis, so no crossing over or independent assortment, and no random fertilisation.Asexual reproduction is common in bacteria, protoctists, fungi and plants, and occurs in some animals such as Hydra and starfish. The main forms, each covered in the following lessons, are sporulation, regeneration (fragmentation), budding and vegetative propagation.Advantages
• Only one parent is needed, so no time or energy is spent finding a mate.
• It is fast, so a population can grow rapidly when conditions are good.
• Offspring keep a combination of alleles that already suits a stable environment.Disadvantages
• There is little genetic variation, so if the environment changes (for example a new disease or a change in temperature) the whole population may be equally vulnerable.
• Offspring often grow close to the parent and compete with it for resources such as light, water and nutrients.Many organisms, such as strawberry plants, can reproduce both sexually and asexually, using asexual reproduction to spread quickly and sexual reproduction to produce variation.
• Only one parent is needed, so no time or energy is spent finding a mate.
• It is fast, so a population can grow rapidly when conditions are good.
• Offspring keep a combination of alleles that already suits a stable environment.Disadvantages
• There is little genetic variation, so if the environment changes (for example a new disease or a change in temperature) the whole population may be equally vulnerable.
• Offspring often grow close to the parent and compete with it for resources such as light, water and nutrients.Many organisms, such as strawberry plants, can reproduce both sexually and asexually, using asexual reproduction to spread quickly and sexual reproduction to produce variation.