Meiosis

•The form of cell division by which gametes, with half the number of chromosomes, are produced.

•Meiosis is sexual reproduction.

•Diploid (2n)    ® haploid (n)

The fusion of a sperm and egg to form a zygote

•A zygote is a fertilized egg

•Sex cells divide to produce gametes (sperm or egg).

Gametes have half the # of chromosomes

•four phases:

 a. prophase I

 b. metaphase I

 c. anaphase I

 d. telophase I

Longest and most complex phase 

Synapsis occurs: homologous chromosomes come together 

Humans have 23 pairs of homologous chromosomes

•Homologous pairs (tetrads) carry genes controlling the same inherited traits.

•A method of organizing the chromosomes of a cell in relation to number, size, and type.

•Shortest phase

Orientation of homologous pair to poles