Reproduction

• Sexual reproduction - is the fusion of 2 gametes
• Sexual reproduction:

  • 2 parents involved
  • The fusion of 2 gametes
  • Offspring is genetically different, so lots of variation
  • Involves meiosis
  • Plants and animals
• Each gamete only has 23 chromosomes (usually its 46), so when fused together have 46 chromosomes.
• Asexual reproduction:

  • Only has one parent.
  • No mixing of genetic material, so there will be no gene variation, this means that all offspring are identical clones.
  • Is energy and time efficient, as don't need to find parent/ second parent.
  • Eukaryotic organisms do this by mitosis.
  • Prokaryotic organisms do this by binary fission.
• Advantages of asexual reproduction:

  • Only need one parent.
  • Process is very quick.
  • This allows single organism to colonise new area quickly.
• Disadvantages of asexual reproduction:

  • All off springs are clones, there is no genetic variation. Meaning if a new disease can effect one of the off spring, the rest can also get it.
  • There is also a smaller chance of adapting to a new condition.
• Advantages of sexual reproduction:

  1. There will be lots of genetic variation. So less likely to have every off spring die form same disease (as some will be more resistant to it). Also means off springs are more likely to adapt to changing conditions, allows evolution.
• Disadvantages of sexual reproduction:

  1. Takes more time and energy than asexual reproduction. Due to needing to find a partner.