Asexual - involves one parent cell. cells divide by mitosis. no fusion between gametes, no mixing of genetic information. no variation in the offspring - clones are made.
Sexual - male and female sex cells from two parents. gametes fuse together. formed by meiosis. offspring inherits characterisitcs fom both parents, not identical - introduces variation.
How meiosis works:
1. DNA in parent cell is copied.
2. cell divides twice and each daughter cell gets half the chromsomes.
3. X-shaped chromosome is pulled apart, resulting in four new daughter cells. these are the gametes.
4. each gamete has a single set of chromosomes and is genetically different, random mix of original chromsomes introducing variation.
Fertilisation - two gametes fuse together to make a new cell. cell divides by mitosis to produce new cells. this forms an embryo.
Variation - no variation in asexual reproduction as equal number of chromosomes and genes are identical to the parents. sexual reproduction introduces variation as gametes fuse sharing chromsomes from the two parents to the offspring.
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