lecture 32 - sex linked genetics

Question 1

what is the chromosomal basis of sex in females?

Answer 1

females are XX

Question 2

what is the chromosomal basis of sex in males?

Answer 2

males are XY

Question 3

a gene located on either X or Y chromosome?

Answer 3

sex-linked gene

Question 4

why are males more likely than females to show traits caused by X-linked genes, such as color blindness or hemophilia?

Answer 4

Males only have one X chromosome, so they don’t have a second X to “cancel out” the effect of a problematic gene. Females, with two X chromosomes, can balance out the effect, making them less likely to show the trait but more likely to carry it.

Question 5

who do fathers pass x-linked traits to?

Answer 5

all of their daughters but none of their sons

Question 6

who do mothers pass x-linked traits to?

Answer 6

both sons and daughters

Question 7

why can’t father give y chromosomes to daughters?

Answer 7

the Y chromosome determines male biological sex

Question 8

true or false - Y chromosome contains fewer genes than the X chromosome

Answer 8

true

Question 9

why are boys more likely be color blind then girls?

Answer 9

boys only need one broken X

Question 10

true or false - girls are usually carriers unless they get two broken X’s

Answer 10

true