Sex-Linked Traits

The 23rd pair of chromosomes determines the sex of an individual. What sex chromosomes do males have? (a)  

What sex chromosomes do females have? (b)  

• XX
• XY

Tags

TX.112.42.C.8.B.

Use the Punnett square to answer the questions below.

1) What is the percent chance that a couple will have a male baby?​ (a)  

2) What fraction of offspring is predicted to be female?​ ​ (b)  

• 50%
• 25%
• 75%
• 100%
• 0%

Tags

TX.112.42.C.8.B.

Hemophilia is an X-linked recessive trait that prevents proper blood clotting and results in excessive bleeding when a person is injured. A woman who is a carrier for hemophilia has children with a man who does not have hemophilia. Which of the following predictions about their offspring is correct?

• There is a 100% chance her daughters will be carriers

• There is a 75% chance her sons will inherit the trait

• There is a 25% chance her daughters will have hemophilia

• There is a 50% chance her sons will have hemophilia

Tags

TX.112.42.C.8.B.

If a woman is a carrier of a sex-linked disease, then ​ (a)   of her sons will have the disease. 

If a woman has a sex-linked disease, then ​ (b)   of her sons will have the disease.

• 50%
• 100%
• 25%
• 0%
• 75%

Tags

NGSS.HS-LS3-1

Diseases that are caused by recessive alleles on the X-chromosome are most likely to affect --

• female offspring

• male offspring 

• male and female offspring equally

• none of the offspring

Which of the following genotypes belongs in the red box in the Punnett square?

• X^BX^b
• X^bX^b
• X^bY
• X^BY

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-3

This pedigree represents the inheritance of hemophilia in this family. How many of the females have the hemophilia trait?

• 8

• 5

• 2

• 3

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-3

What do half colored symbols represent?

• The individual is a carrier (heterozygous).
• The individual expresses the trait.
• The individual has both recessive alleles.
• The individual has both dominant alleles.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2