Experiment verification of the chromosomal theory of inheritance was given by
1. Sutton and Boveri
2. Thomas Hunt Morgan
3. de Vries
4. Mendal
In human ABO group system ________ different alleles allow the possibility of _______ different types of genotypes in population.
1. 3, 4
2. 2, 4
3. 3, 6
4. 6, 3
The phenotype of an individual may be affected if the modified allele produces
A. The normal/less efficient enzyme
B. No enzyme at all
C. A non-functional enzyme
1. Only A is correct
2. Only C & A are correct
3. Only B is correct
4. B & C are correct
Ability of a gene to have multiple phenotypic effects is known as
1. Co-dominance
2. Pleiotropy
3. Multiple allelism
4. Incomplete dominance
Morgan and his group observed when the two genes in a dihybrid cross were situated on the same chromosome, the proportion of parental gene combinations were much higher than the non-parental type, this is due to
1. Independent assortment
2. Linkage
3. Crossing over
4. Competence
What is probability of homozygous individuals for both characters in generation of a dihybrid cross?
1. 1/2
2. 3/4
3. 1/3
4. 1/4
Choose correct option with respect to given figure for determination of sex by chromosomal differences.
1. b after spermatogenesis forms only one type of gametes
2. b & c represents same sex
3. a, d are heterogametic
4. Sex determination in d is similar to grasshopper
Which one of the following statement is incorrect?
1. | Sturtevant used the frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes |
2. | Sutton and Boveri argued that the pairing and separation of a pair of chromosomes would lead to the segregation of a pair of factors they carried. |
3. | Y-linked genes are holandric |
4. | 7 : 1 : 1 : 7 as linkage ratio in case of dihybrid test cross means that there are 8 parental and 8 recombinant plants |
The figure below shows the chromosome segregation during germ cells formation with four stages labelled as (A), (B), (C) and (D). Select the right option giving all the four stages correctly identified
1. (A) Interphase (B) Metaphase-l
(C) Telophase-l (D) Anaphase-ll
2. (A) (B)
(C) Anaphase-l (D) Anaphase-ll
3. (A) (B)
(C) Metaphase-l (D) Anaphase-l
4. (A) (B)
(C) Anaphase-l (D) Metaphase-ll
Males are heterogametic and females are homogametic in
1. Human beings and birds
2. Fruit fly and butter fly
3. Grasshopper and cockroach
4. Birds and silkworm