Select the correct match:

1.	Phenylketonuria	Autosomal dominant trait
2.	Sickle cell anemia	Autosomal recessive trait chromosome - 11
3.	Thalassemia	X linked
4.	Haemophilia	Y linked

A primary non-disjunction event involving an autosome may lead to:
1. Down’s Syndrome
2. Klinefelter’s syndrome
3. Turner’s syndrome
4. Cushing’s syndrome

Identify the incorrectly matched pair:

A dihybrid test cross results in a 50% frequency of recombinants in progeny. This shows that:
1. The two genes are most likely located on different chromosomes
2. One of the genes must be located on the X chromosome
3. The two genes are closely linked on the same chromosome
4. The two genes must be pleiotropic

The rediscovery of Mendel’s laws is credited to:
1. Morgan and Sturtevant
2. Knight and Goss
3. de Vries, Correns and Tschermak
4. Avery, Macleod and McCarty

The male honeybees:
1. do not have father and cannot have sons
2. do not have father but can have sons
3. do not have grandfather and cannot have grandsons
4. do not have father and do not have grandfather

A couple has a son. What is the probability that their next child will be a daughter?
1. ½
2. 1
3. 0
4. ¼

In a human population, 1 in 10,000 are affected with an autosomal recessive disorder. What proportion of that human population is likely to be a carrier of the recessive allele?
1. approximately 0.02
2. approximately 0.19
3. approximately 0.98
4. approximately 0.2

The ability of one genotype to produce more than one phenotype when exposed to different environments is called as:
1. Developmental noise
2. Norm of the reaction
3. Phenotypic plasticity
4. Variable expressivity

Presence of a Barr body, a Y chromosome in the karyotype and the affected individual having gynecomastia point to:
1. Klinefelter’s syndrome
2. Cri-du-chat syndrome
3. Turner’s syndrome
4. Edward’s syndrome