Download In Humans what is the gene responsible for the development of

1. In Humans what is the gene responsible for the development of testes and secondary male
characteristic? SRY
2. What is true regarding human sex chromosomes?
a. The woman always inherits a Y from her fathers father
b. The man always inherits his Y from his mother’s father
c. The man always inherits his X from his fathers mother
d. The women always inherits her X from her fathers mother
3. Given the following cross: AaBbCC x AaBbCC, what is the probability of obtaining an
offspring with the genotype, AABbCC assuming all loci are independently assorting?
(¼)(2/4)(4/4)=8/64
4. Larry is color blind, an X linked recessive disorder. He marries Maria who is not color
blind, but Maria’s brother Steve is color blind. Maria’s and Steve’s mother is colorblind.
What is the probability that Larry and Maria’s son will inherit color blindness? ½
Maria XAXa* Larry XaY
XAY, XaY only half males will be color blind
5. Four babies are born in a hospital, and each has a different blood type: A, B, AB, and
O. The parents of these babies have the following pairs of blood types A and B, O and O,
AB and O, and B and B. Which baby belongs to which parents?
Parent
Baby
A+B
AB
(IAIA) (IBIB)
(IAIB)
O +O
O
(ii) (ii)
(ii)
AB+O
A
(IAIB) (ii)
(IAi)
B+B
B
B
B
B
B
(I I ) (I I )
(IBIB)
6. What happens at the conclusion of meiosis I? homologous chromosomes are separated
7. How do sexual lifecycles increase genetic variability? Random fertilization, crossing
over, independent assortment of homologous chromosomes
8. In cats the Manx allele (M) causes short or absent tail, while a recessive allele m confers
a normal long tail. Cats of genotype MM die as embryos. If two Manx cats mate what is
the probability that each surviving kitten has a long tail? ¼ long tail or mm
P gen
Mm *Mm (parents can’t be MM)
F1 gen
1 MM, 2 Mm, 1mm