AP BIOLOGY

HEREDITY

SEX LINKAGE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
How many recessive genes does a carrier female have for colorblindness? (Colorblindness is an x-linked recessive trait.)
A
1
B
2
C
0
Explanation: 

Detailed explanation-1: -Chromosome and Females contain two x chromosomes. So males, it only takes one affected X chromosome to have the disease Women it would take two X chromosomes.

Detailed explanation-2: -Most commonly, color blindness is inherited as a recessive trait on the X chromosome. This is known in genetics as X-linked recessive inheritance. As a result, the condition tends to affect males more often than females (8% male, 0.5% female).

Detailed explanation-3: -Females have two X chromosomes, while males have one X and one Y chromosome.

Detailed explanation-4: -Men have one X chromosome and one Y chromosome, while women have two X chromones. To experience color blindness, the genetic mutation for colorblindness must be present on the X chromosome, but for women, this means it must be present on both X chromones.

Detailed explanation-5: -Females can get an X-linked recessive disorder, but this is very rare. An abnormal gene on the X chromosome from each parent would be required, since a female has two X chromosomes.

There is 1 question to complete.