Meiosis and Sexual Reproduction Chapter 7

Meiosis Formation of gametes The process of cutting chromosome number in half 2 Divisions Reduction Production

Let’s Make a Gamete : 1. Prophase 1 Chromosomes become visible Nucleus breaks down

Prophase 1: Crossing Over Crossing over occurs Portions of a chromatid on one homologous chromosome are broken and exchanged with the corresponding portions on the other homologous chromosome

Creates Genetic Diversity !!!!!! Survial of a species

Metaphase 1 Pairs of chromosomes move to middle of the cell

AnaPhase 1 Homologous pairs move to opposite ends of the cell

Telophase 1 and cytokinesis Chomosomes move to end of cell Cytoplasm divides Chromosome number cut in half!!!!!!!

Division 2 Meiosis

Prophase II Happens in both cell at the same time A new spindle forms

Metaphase II Chromosomes line up at the equator

Anaphase II Centromeres divide Chromosomes move to opposite ends of cells

End of Meiosis

Telephase II Nuclear membrane reappears Cytokinesis Result: ? 4 Haploid Gametes Egg (ovum) Sperm

Meiosis Animation

White Boarding

Name this phase?

Name this phase?

Phase? Haploid or diploid

Phase?