Miesis

  • Somatic cells = Body cells 

    • These are diploid (2n)

    • Ex. Blood cells, lung cells, muscle cells, heart cells, etc.  

  • Gametes = Reproductive cells

    • These are haploid (n)

    • Ex. Egg and sperm

  • Diploid Cells = 2 full sets of chromosomes

    • (2n)

    • A set from parent 1 and a set from parent 2

    • Ex. In human somatic cells, 2n = 46

  • Haploid Cells = 1 full set of chromosomes

    • (n)

    • Only one set that is a combination of chromosomes from parents

    • Ex. Gametes = egg and sperm, n = 23

  • Autosomes

    • Carry traits that make you who you are

    • Ex. The 1st 22 pairs of chromosomes

  • Sex Chromosomes

    • Carry traits that make you who you are AND contribute to your biological sex

    • Ex. The 23rd pair of chromosomes (X or Y)

    Sexual reproduction = organisms that reproduce sexually (like humans) fuse the genetic information (gametes) from two parents to produce offspring that are a genetic mixture of both parents.


    Fertilization = the actual fusion of egg and sperm to form a zygote.

  • Homologous chromosomes = chromosome pairs that have the same types of genes

    • One from each parent

  • Sister chromatids = 2 identical copies of the same chromosome