Mitosis and Variation

  • Created by: amy24601
  • Created on: 30-01-20 20:15
View mindmap
  • Mitosis and Variation
    • Chromosomes
      • each cell contains 46 chromosomes
      • sperm and egg cells have 23 chromosomes each. this is so that when they join together to make a zygote those cells have 46 chromosomes
      • You have two chromosomes for each gene or characteristic
    • stages of mitosis
      • stage 1: cell gets ready to divide. duplicates each of its chromosomes
      • stage 2: chromosomes line up along the middle of the cell (the equator)
      • stage 4: the cell splits and two new identical daughter cells are formed.
      • stage 3: the identical chromatids are pulled apart by spindle fibres to opposite sides of the cell.
    • variation
      • a species is a group of organisms that can interbreed and produce fertile offspring.
      • two animals can reproduce but if they're nor the same species their offspring will be infertile.
      • continuous variation falls smoothly from one extreme to another. there isn't two distinct groups. eg- height or hair colour.
      • discrete variation means you can divide a species into two distinct groups. eg- what hand you write with or if you can roll your tongue or not.


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Biology resources »