Variation and genetics – Online MCQs Test – Biology MCAT

1. Cross appearance of intermediate character is known as:

Epistasis

Incomplete dominance

Co dominance

Test cross

2. ________ pairs of chromosomes found in Drosophila:

Four

Two

Five

Three

3. What is the most common outcome in the F2 generation of a cross between a tall plant and a dwarf plant?

All tall

3tall : 1 dwarf

1 tall : 1 dwarf 1

1 tall : 2 medium : 1 dwarf

4. When a colour blind male marries a normal female:

All the sons, will be normal & daughter colour blind.

All the sons and daughters will be colour blind.

All the daughters will be colour blinds & sons normal but cariers.

All sons are colour blind & daughters normal but carriers.

5. Which of the followings is not continuously varying trait?

Red white flower

Human height

Cornel colour insect

Human skin colour

6. Incomplete dominance is also known as:

Dependent Inheritance

Primary Inheritance

Secondary Inheritance

Intermediate inheritance

7. Mendel perform his famous experiments of heredity on:

Castor plant

Mirabilis plant

Maize

Garden pea

8. The blood group without antigen is:

9. Genes A and B are necessary for normal hearing. A deaf man marries a deaf woman and all their children have normal hearing. The genotypes of the parents are:

Aabb and aaBb

AAbb and aaBB

AAbb and Aabb

aaBB and aaBB

10. Which one of the following crosses shows 3: 1 ratio?

aabb x AABB

AaBb x aabb

AaBb x AaBb

Aabb x Aabb

11. Regarding colour blindness, “when a normal male marries carrier female”, which is the correct statement?

Half of the sons will be colour blind

All sons will be colour blind

All daughter will be colour blind

All daughters are normal but carriers

12. Erythroblastosis fetal is can occur if marriage occurs between

B & D are correct

Rh+ male Rh+ female

Rh+ male Rh- female

Rh- male, Rh- female

13. One of the x chromosomes of a woman bears two linked genes for haemophillic and colour blindness. She marries a normal man. How will the progeny be?

50% haemophillic colour-blind sons and 50% normal sons

Haemophillic colour-blind daughters

All sons and daughters are haemophillic and colour-blind

50% haemophillic daughters and 50% colour blind daughters

14. An individual with contrasting alleles is called

Monoecious

Dioecious

Heterozygous (hybrid)

Homozygous (pure)

15. The members of one pair of genes segregate independently of the other pairs, this is:

Pleiotropy

Law of independent Assortment

Law of Segregation

Law of Dominance

16. Blood group also known as “Universal Recipient” is:

Blood group B+

Blood group A+

Blood group B-

Blood group O+

17. Which of the following condition represents a case of co-dominant genes?

A gene expresses itself suppressing the phenotypic effect of its alleles, when present in Heterozygous condition.

Genes that are similar in phenotypic effect, when present separately, but when together interact to produce different unit

Alleles both of which interact to produce a trait which mayor may not resemble either of the parental types

Alleles, each of which produces an independent effect in a heterozygous condition

18. Mutual exchange of segments of chromosomes is called:

Pleiotropy

Crossing over

Linkage

Synapsis

19. A gene for a trait having three or more allelic forms is called:

Unilocular alleles

Multiple alleles

Single allele

Double alleles

20. Each human being possesses ________ pairs of chromosomcs.

Variation and genetics / inheritance-Medical College Admission Test Preparation Notes