7.5 chromosomal abnormalities

Question 1

What is nondisjunction?

Answer 1

When chromosomes do not separate properly.

Question 2

How can nondisjunction happen in meiosis l?

Answer 2

Homologous chromosomes do not separate

Question 3

How can nondisjunction affect cells?

Answer 3

Cells can have no chromosomes or too many

Question 4

What is x-chromosome inactivation?

Answer 4

When each cell randomly inactivates one x-chromosome which becomes an inactive bar body which shrivels up and becomes silent

Question 5

Why are humans more tolerant of extra sex chromosomes?

Answer 5

y chromosomes are not essential to human life and extra x chromosomes get deactivated by x chroosome inactivation.

Question 6

What are autosomes?

Answer 6

chromosomes #1-22

Question 7

What are other chromosome abnormalities?

Answer 7

deletion, duplication, inversion, translocation

Question 8

How is sex determined?

Answer 8

If you get a y chromosome

Question 9

What is the result of deletion?

Answer 9

Missing genes