Meiosis and Genetic Variation

Question 1

What occurs in Prophase 1?

Answer 1

• Homologous chromosomes pair up to form tetrads

- Genetic variation and crossing occurs between tetrads

Question 2

What occurs in Metaphase 1?

Answer 2

• Nuclear envelope breaks down
• Tetrads like up at the metaphase plate
• Centrosomes head to poles

Question 3

What occurs in Anaphase 1?

Answer 3

Centrosomes with microtubules pull tetrads apart and sister chromosomes get pulled to opposite poles

Question 4

What occurs in Telophase 1?

Answer 4

chromosomes at each pole

Question 5

What occurs in Cytokinesis 1?

Answer 5

2 Haploid cells form

Question 6

What occurs in Prophase 2, Metaphase 2, Anaphase 2, Telophase 2 and Cytonikesis 2?

Answer 6

Same as Mitosis

Question 7

What is independent assortment?

Answer 7

The random assortment of tetrads on the metaphase plate

some of dads can go to one side and some of moms can go to the other - random

Question 8

What is crossing over?

Answer 8

Similar genes from each chromosome on a tetrad switch to the other chromosome on the tetrad

Question 9

What is random fertilization?

Answer 9

Any sperm can fuse with any egg