1. Hemophilia is a bleeding disorder that primarily affects males. Those with the recessive, sex linked genetic disorder have issues with their blood clotting which can lead to severe issues with even minor injuries. Using what you know about sex-linked and recessive traits, why is it more common for males to have this disorder?
A. It is carried on the X chromosome, and since males have two X's they have twice the chance of getting it whereas females only have one X and are half as likely to receive it
B. It is carried on the Y chromosome, and females do not have that
C. It is carried on the X chromosome, and since it is recessive, females have two chances to receive a dominant allele and males only have one chance
D. It is carried on the Y chromosome, and since it is recessive, males stand a higher chance of receiving two copies of the recessive gene since they have two Y chromosomes and females only have one
2. "Sickle cell anemia is caused by having two recessive copies of a trait. Being heterozygous for this trait provides protection to malaria (which is a life threatening blood disease spread by mosquitoes) and shows no adverse effects. Being heterozygous therefore can be lifesaving in countries such as Africa, where malaria is the most common. If a person is homozygous recessive for sickle cell trait, however, they will have sickle cell anemia, where red blood cells become shaped like "sickles" (or crescent moons) and comes with a wide area of severe issues." What are the chances of a homozygous dominant individual and a homozygous recessive individual having a child with sickle cell anemia?
A. 0%
B. 25%
C. 50%
D. 75%
E. 100%
3. If the DNA sequence is TCA, what would the mRNA sequence be? What would the tRNA sequence be?
A. UGT, TGU
B. AGU, UCA
C. UGU, UCA
D. AGT, TCA
1. A. It is carried on the X chromosome, and since males have two X's they have twice the chance of getting it whereas females only have one X and are half as likely to receive it.
2. B. 25%.
3. B. AGU, UCA.