3. MEIOSIS: NON DISJUNCTION

Click here to view an animation on meiosis and the consequences of non disjunction.
Questions:
1. In this animation, when does non-disjunction occur?
2. What fails to separate in this animation?
3. If the the gamete producing cells has 4 chromosomes, how many chromosomes should each gamete contain?

2. MEIOSIS: NON DISJUNCTION

This website shows three animations: 1) crossing over, 2) normal meiotic division in females and fertilization, and 3) non disjunction in Down Syndrome. Also, click on the last box to view an animated power point on meiosis and fertilization.

Questions:
1. What is the difference between spermatogenesis and oogenesis?
2. In humans, how many chromosomes are present in the gametes?
3. In humans, how many chromosomes are present in somatic cells?
4. How do somatic cells divide?

1. MEIOSIS: NONDISJUCTION

Click here to watch an animation non disjunction during meiosis.

Questions:
1. In this animation, at what stage of meiosis does non disjunction occur?
2. What is the result of non disjunction?