Presentation is loading. Please wait.

Presentation is loading. Please wait.

11.2 Meiosis I. What Happens During Meiosis

Similar presentations


Presentation on theme: "11.2 Meiosis I. What Happens During Meiosis"— Presentation transcript:

1 11.2 Meiosis I. What Happens During Meiosis
A. Meiosis halves the number of chromosomes 1. Crossing Over a. paired chromosomes exchange segments of DNA 2. Skipping Replication a. Only one replication of DNA but two divisions II. Meiosis I A. Prophase I 1. Chromosomes condense, nuclear envelope disappears, & crossing over occurs B. Metaphase I 1. Chromosomes moved to equator by spindle fibers. 2. Two chromatids remain together 3. Independent assortment a. Random distribution of homologous chromosomes

2 C. Anaphase I 1. Homologous chromosomes separate & are pulled to opposite ends 2. Chromosomes do not separate at centromeres D. Telophase I 1. The two new cells contain half the number of chromosomes 2. Called reduction division III. Meiosis II A. Identical to stages of mitosis with a few exceptions 1. Chromosomes do not replicate before they divide 2. In the end 4 haploid cells are created IV. Genetic Recombination A. Two chromosomes no longer contain identical genetic material B. Allow for genetic variation which can impact how fast species evolve

3


Download ppt "11.2 Meiosis I. What Happens During Meiosis"

Similar presentations


Ads by Google