Consider the following statements:

I. People affected by phenylketonuria are unable to convert tyrosine to phenylalanine.

II. Alzheimer's disease results from accumulation of amyloid protein plaques in the brain.

III. Klinefelter's and Turner's syndromes are the result of non disjunction of the sex chromosomes in either of sexes.

Which of the above statements are true?

1. I and II only

2. I and III only

3. II and III only

4. I, II and III

Consider the following statements:

I. If we put them through test cross, all homozygous dominant combinations will breed true but heterozygous genotypes will follow the segregation.

II. Two gene interactions such as epistasis do not follow the Menedelian principle of segregation.

III. In any diploid individual, only two alleles can be found, so multiple alleles can be detected only in a population.

Which of the above statements are true?

1. I and II only

2. I and III only

3. II and III only

4. I, II and III

A gene showing codominance has

(1) one allele dominant on the other

(2) alleles tightly linked on the same chromosome

(3) alleles that are recessive to each other

(4) both alleles independently expressed in the heterozygote

In his classic experiments on pea plants, Mendel did not use

(1) seed colour

(2) pod length

(3) seed shape

(4) flower position

How many pairs of contrasting characters in pea plants were studied by Mendel in his experiments?

(1) Five

(2) Six

(3) Eight

(4) Seven

Which one from those given below is the period of Mendel's hybridisation experiments?

(1) 1856 - 1863

(2) 1840 - 1850

(3) 1857 - 1869

(4) 1870 - 1877

Among the following characters, which one was not considered by Mendel in his experiments on pea?

(1) Stem - Tall or Dwarf

(2) Trichomes - Glandular or Non-glandular

(3) Seed - Green or Yellow

(4) Pod - Inflated or Constricted

Thalassemia and sickle-cell anaemia are caused due to a problem in globin molecule synthesis. Select the correct statement.

(1) Both are due to a qualitative defect in globin chain synthesis

(2) Both are due to a quantitative defect globin chain synthesis

(3) Thalassemia is due to less synthesis of globin molecules

(4) Sickle-cells anaemia is due to a quantitative problem of globin molecules

A disease caused by an autosomal primary non-disjunction is 

(1) Down's syndrone

(2) Kilnerfelter's syndrome

(3) Turner's syndrome

(4) Sickle-cell anemia

The mechanism that causes a gene to move from one linkage group to another is called 

(1) inversion

(2) duplication

(3) translocation

(4) crossing-over