Meiosis Phases

Before Meiosis I - Interphase Each chromosome is replicated and each chromosome pairs up with its homolog = tetrad homologous chromosomes = tetrad Sister chromatids

Prophase I: Homologous chromosomes pair and cross over Nuclear membrane disappears Centrioles appear and begin to form spindle fibers .

Metaphase I: Chromosomes line up at the center of the cell paired with their homolog Spindle fibers attach to the centromere .

Anaphase I The spindle fibers pull the homologous chromosomes toward opposite ends of the cells Notice the results of ‘crossing over’ .

Telophase I / Cytokinesis: Nuclear membranes form and the cell separates into 2 daughter cells Each daughter cell contains only one chromosome of the homologous pair Cells are now haploid .

Between Telophase I and Prophase II, the DNA is NOT replicated again: the cell goes into meiosis II

Prophase II: Nuclear envelopes dissolve, and spindle fibers reform

Metaphase II: Chromosomes line up at the center of the cell

Anaphase II: The sister chromatids separate and move towards opposite ends / poles of the cell

Telophase II / Cytokinesis: Cell division is complete One parent cell has produced four haploid daughter cells