Principles of Inheritance and Variation

The recombination frequency between the genes a & c is 5%, b & c is 15%, b & d is 9%, a & b is 20%, c & d is 24% and a & d is 29%. What will be the sequence of these genes on a linear chromosome?

1. a, d, b, c
2. d, b, a, c
3. a, b, c, d
4. a, c, b, d

Given below are two statements: In the light of the above statements, choose the correct answer from the options given below :

1. Statement I is incorrect but Statement II is correct
2. Both Statement I and Statement II are correct
3. Both Statement I and Statement II are incorrect
4. Statement I is correct but Statement II is incorrect

The chromosomal theory of inheritance was proposed by

1. Robert Brown
2. Thomas Morgan
3. Sutton and Boveri
4. Gregor Mendel

What is the expected percentage of F2 progeny with yellow and inflated pod in dihybrid cross experiment involving pea plants with green coloured, inflated pod and yellow coloured constricted pod?

1. 9%
2. 100%
3. 56.25%
4. 18.75%

If a female individual is with small round head, furrowed tongue, partially open mouth and broad palm with characteristic palm crease. Also the physical, psychomotor and mental development is retarded. The karyotype analysis of such an individual will show :

1. Trisomy of chromosome 21
2. 47 chromosomes with XXY sex chromosomes
3. 45 chromosomes with XO sex chromosomes
4. 47 chromosomes with XYY sex chromosomes

Select the incorrect match regarding the symbols used in the Pedigree analysis:

1. [figure] – Parent with male child affected with disease
2. [figure] – Sex unspecified
3. [figure] – Affected individual
4. [figure] – Consanguineous mating

A normal girl, whose mother is haemophilic marries a male with no ancestral history of haemophilia. What will be the possible phenotypes of the offspring? Choose the most appropriate answer from the options given below:

1. B and D only
2. A and B only
3. B and C only
4. A and D only

The production of gametes by the parents, formation of zygotes, the F1 and F2 plants, can be understood from a diagram called :

1. Net square
2. Bullet square
3. Punch square
4. Punnett square

In a cross between a male and female, both heterozygous for sickle cell anaemia gene, what percentage of the progeny will be diseased?

1. 100%
2. 50%
3. 75%
4. 25%

Experimental verification of the chromosomal theory of inheritance was done by

1. Sutton
2. Mendel
3. Morgan
4. Boveri

Select the correct match

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

Identify the wrong statement with reference to the gene ‘I’ that controls ABO blood groups.

1. Allele ‘i’ does not produce any sugar.
2. The gene (I) has three alleles.
3. When IA and IB are present together, they express same type of sugar.
4. A person will have only two of the three alleles.

How many true breeding pea plant varieties did Mendel select as pairs, which were similar except in one character with contrasting traits?

1. 14
2. 4
3. 2
4. 8

The frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes was explained by :

1. Alfred Sturtevant
2. Gregor J. Mendel
3. Sutton Boveri
4. T.H. Morgan

In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F1 generation, pink flowers were obtained. When pink flowers were selfed, the F2 generation showed white, red and pink flowers. Choose the incorrect statement from the following :

1. Ratio of F2 is 14 (Red) : 24 (Pink) : 14 (White)
2. Law of Segregation does not apply in this experiment
3. This experiment does not follow the Principle of Dominance
4. Pink colour in F1 is due to incomplete dominance

What map unit (Centimorgan) is adopted in the construction of genetic maps?

1. A unit of distance between genes on chromosomes, representing 1\% cross over.
2. A unit of distance between genes on chromosomes, representing 50\% cross over.
3. A unit of distance between two expressed genes, representing 10\% cross over.
4. A unit of distance between two expressed genes, representing 100\% cross over.

What is the genetic disorder in which an individual has an overall masculine development, gynaecomastia, and is sterile?

1. Edward syndrome
2. Down’s syndrome
3. Turner’s syndrome
4. Klinefelter’s syndrome

Select the incorrect statement.

1. In domesticated fowls, sex of progeny depends on the type of sperm rather than egg.
2. Human males have one of their sex-chromosome much shorter than the other.
3. Male fruit fly is heterogametic
4. In male grasshoppers, 50\% of sperms have no sex-chromosome.

Which of the following pairs is wrongly matched?

1. Starch synthesis in pea : Multiple alleles
2. ABO blood grouping : Co-dominance
3. XO type sex determination: Grasshopper
4. T.H. Morgan : Linkage

Which of the following characteristics represent 'Inheritance of blood groups' in humans?

1. B, C and E only
2. A, B and C only
3. B, D and E only
4. A, C and E only

A woman has an X-linked condition on one of her X chromosomes. This chromosome can be inherited by

1. only daughters
2. only sons
3. only grandchildren
4. both sons and daughters

Select the correct statement :

1. Franklin Stahl coined the term “linkage”.
2. Punnett square was developed by a British scientist.
3. Spliceosomes take part in translation.
4. Transduction was discovered by S. Altman.

Thalassemia and sickle cell anemia 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. Thalassemia is due to less synthesis of globin molecules
3. Sickle cell anemia is due to a quantitative problem of globin molecules
4. Both are due to a quantitative defect in globin chain synthesis

The genotypes of a Husband and Wife are IAIB and IAi. Among the blood types of their children, how many different genotypes and phenotypes are possible?

1. 4 genotypes ; 3 phenotypes
2. 4 genotypes ; 4 phenotypes
3. 3 genotypes ; 4 phenotypes
4. 3 genotypes ; 3 phenotypes

A disease caused by an autosomal primary non-disjunction is :

1. Klinefelter's Syndrome
2. Down's Syndrome
3. Turner's Syndrome
4. Sickle Cell Anemia

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

1. 1870 – 1877
2. 1857 – 1869
3. 1840 – 1850
4. 1856 – 1863

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

1. Stem-Tall or dwarf
2. Pod-Inflated or constricted
3. Trichomes-Glandular or non-glandular
4. Seed-Green or yellow

A cell at telophase stage is observed by a student in a plant brought from the field. He tells his teacher that this cell is not like other cells at telophase stage. There is no formation of cell plate and thus the cell is containing more number of chromosomes as compared to other dividing cells. This would result in -

1. Polyteny
2. Aneuploidy
3. Polyploidy
4. Somaclonal variation

Pick out the correct statements :

1. A, B and C only
2. A, C and D only
3. A and D only
4. B and D only

A tall true breeding garden pea plant is crossed with a dwarf true breeding garden pea plant. When the F1 plants were selfed the resulting genotypes were in the ratio of -

1. 3 : 1 :: Tall : Dwarf
2. 1 : 2 : 1 :: Tall heterozygous : Tall homozygous : Dwarf
3. 1 : 2 : 1 :: Tall homozygous : Tall heterozygous : Dwarf
4. 3 : 1 :: Dwarf : Tall