Who rediscovered Mendel’s laws?

(1) de Vries

(2) Correns

(3) Von Tschermak

(4) all of these

Pairing and separation of a pair of chromosomes would lead to segregation of a pair of factors they carried. This conclusion was drawn by

(1) Walter Sutton

(2) Theodore Boveri

(3) both (1) and (2)

(4) Thomas Hunt Morgan

Chromosomal theory of inheritance is a combination of

(1) Knowledge of chromosomal segregation with Mendelian principle

(2) Knowledge of Dihybridcross with motion of chromosome

(3) Knowledge of Law of dominance with chromosomal appearance

(4) Knowledge of classical genetics with modern molecular biology

The behaviour of chromosomes and genes can be compared with each other is best explained by which of the following statement?

(1) occur in nucleus

(2) both segregate at the time of gamete formation leading to transmittance of complete pair to a gamete.

(3) Independent pairs( gene) or pair of chromosomes segregate independently of each other or of other pair.

(4) The two alleles of a gene pair are located on homologous site on homologous chromosomes.

The chromosome movement during meiosis have been worked out

(1) 1900

(2) 1902

(3) 1911

(4) 1930

Consider the following statement and find out the incorrect one:

(1) Advancement in Microscopy made the study of chromosomal behaviour possible.

(2) The two alleles of a gene pair are located on homologous site on homologous chromosomes.

(3) Experimental verification of chromosomal theory of Inheritance was done by T. H. Morgan et. Al.

(4) Morgan Chose Drosophila as an experimental animal because it has variations that can be seen with high power of microscope.

Linkage was described by Morgan in Drosophila. Which of the following combinations are correct?

(i) He hybridised yellow bodied, white-eyed females to brown-bodied, red eyed males and then intercrossed their F₁

(ii) The ratio of F₂ generation is same as that of 9:3:3:1 in this cross.

(iii) The parental combinations are observed more than recombinants.

(iv) According to Morgan Linkage was observed due to chemical association of genes.

(v) All the genes present on same chromosomes have same efficiency to link.

(1) (ii), (iv), (v)

(2) (i), (iii)

(3) (i), (iii), (v)

(4) (i) and (iv)

Mendel’s success was largely due to his choice of the garden pea plant for his experiments. The advantages of using this plant included:

I. Presence of easily observable contrasting traits for many characters.
II. It was possible to control pollination [and hence mating] between different pea plants.
III. A large number of seeds could be produced and statistical analysis was therefore more accurate.
IV. A long generation time means expression of all traits completely.
V. Many observable traits were controlled by single genes.

1. Only I, II and III
2. Only I, II and V
3. Only I, II, III and V
4. Only II, III, IV and V

What was the most significant conclusion that Gregor Mendel drew from his experiments with pea plants?

An organism with two copies of the same allele is: