Reproduction

• each gamete has 23 chromosomes
• the egg and sperm cell fuse together
• sexual reproduction involves the fusion of male and female gamete’s because there are two parents, the offspring contain a mixture of their parents’ gene
• offspring inherits features from both parents producing variation in the offspring
• asexual reproduction 


  1 parent

  offspring genetically identical (clone)

  reproduction happens by mitosis

  bacteria, some plants and some animals reproduce asexually
• gametes only have one copy 1 chromosome each so when gamete fusion takes place, you get the right amount of chromosomes again
• after 2 gametes have fused during fertilisation, the resulting new cell divides by mitosis to make a copy of itself
• mitosis repeats many times to produce lots of new cells in an embryo. As the embryo develops these cells then start to differentiate into the different types of specialised cells that make up a whole organism