Role of Mitosis
Biology: Cambridge International A Level, topic 5.1.4
The Significance of Mitosis in Life Cycles
Mitosis is a vital process to nearly every living organism. Bacteria and other unicellular organisms largely rely on mitosis for reproduction, while multicellular organisms need mitosis in order to grow and repair tissues.
Asexual reproduction
- Single celled organisms reproduce via mitosis as cellular and organismal levels of organisation are the same for them, cell division represents reproduction of entire organisms.
- Mitosis produces identical cells, so reproduction via this method produces clonal organisms. This means entire colonies of bacteria are likely to be identical to each other.
- This form of reproduction is known as asexual as there is no meiosis and shuffling of genes.
- Asexual reproduction only requires one parent cell, allowing single celled organisms to increase population rapidly.
- Mitosis introduces no genetic variation into populations so bacteria rely on alternative methods, such as horizontal gene transfer of plasmids for variation.
Growth
- Multicellular organisms must grow through increasing their cell count.
- Mitosis is vital as it allows somatic (body) cells to reproduce and form clones that can perform the exact same function within the body as parent cells.
Tissue repair
- When damaged or injured, an organism can replace the lost cells via mitosis.
- Structures such as skin and bones can be reconstructed with new cells produced from mitosis, while lost fluids such as blood can be replenished in this way too.
- Some organisms such as axolotls are able to replace entire limbs and tails via mitosis.
Test yourself on Role of Mitosis
Which of these statements about mitosis are true?
How many parent cells does asexual reproduction require?