Principles of Inheritance and Variation · Biology · NEET

Given below are two statements:

Statement I: When many alleles of a single gene govern a character, it is called polygenic inheritance.

Statement II: In Polygenic inheritance, the effect of each allele is additive.

In the light of the above statements, choose the correct answer from the options given below.

Match List-I with List-II:

Choose the correct answer from the options given below:

When a tall pea plant with round seeds was selfed, it produced the progeny of :

(a) Tall plants with round seeds and

(b) Tall plants with wrinkled seeds.

Identify the genotype of the parent plant.

Aneuploidy is a chromosomal disorder where chromosome number is not the exact copy of its haploid set of chromosomes, due to :

A. Substitution

B. Addition

C. Deletion

D. Translocation

E. Inversion

Choose the most appropriate answer from the options given below :

The mother has $$\mathrm{A}+$$ blood group the father has $$\mathrm{B}+$$ and the child is $$\mathrm{A}+$$. What can be the possibility of genotypes of all three, respectively?

A. $$I^A I^A|I B i| I^B i$$

B. $$I^A I^A\left|I^B i\right| I^A i$$

C. $$I^B i\left|I^A I^A\right| I^A I^B$$

D. $$\left|A \beta^A\right| I^B I^B \mid I^A i$$

E. $$I^A i\left|I^B i\right| I^A i$$

Choose the correct answer from the option given below:

Which one of the following can be explained on the basis of Mendel's Law of Dominance?

A. Out of one pair of factors one is dominant and the other is recessive.

B. Alleles do not show any expression and both the characters appear as such in F$$_2$$ generation.

C. Factors occur in pairs in normal diploid plants.

D. The discrete unit controlling a particular character is called factor.

E. The expression of only one of the parental characters is found in a monohybrid cross.

Choose the correct answer from the options given below:

A pink flowered Snapdragon plant was crossed with a red flowered Snapdragon plant. What type of phenotype/s is/are expected in the progeny?

In a plant, black seed color $$(\mathrm{BB} / \mathrm{Bb})$$ is dominant over white seed color $$(\mathrm{bb})$$. In order to find out the genotype of the black seed plant, with which of the following genotype will you cross it?

Match List I with List II

Choose the correct answer from the options given below:

As per ABO blood grouping system, the blood group of father is $$\mathrm{B}^{+}$$, mother is $$\mathrm{A}^{+}$$ and child is $$\mathrm{O}^{+}$$. Their respective genotype can be

A. I^Bi/I^Ai/ii

B. I^BI^B/I^AI^A/ii

C. iI^B/iI^A/I^AIB

D. I^Ai/I^Bi/I^Ai

E. iI^B/iI^A/I^AI^B

Choose the most appropriate answer from the options given below :

Match List - I with List - II.

Choose the correct answer from the options given below :

A heterozygous pea plant with violet flowers was crossed with homozygous pea plant with white flower. Violet is dominant over white. Which one of the following represents the expected combinations among 40 progenies formed?

In which disorder change of single base pair in the gene for beta globin chain results in change of glutamic acid to valine ?

A certain plant homozygous for yellow seeds and red flowers was crossed with a plant homozygous for green seeds and white flowers. The F₁ plants had yellow seeds and pink flowers. The F₁ plants were selfed to get F₂ progeny. Assuming independent assortment of the two characters, how many phenotypic categories are expected for these characters in the F₂ generation ?

Select the correct statement/s with respect to mechanism of sex determination in Grasshopper.

(A) It is an example of female heterogamety.

(B) Male produces two different types of gametes either with or without X chromosome.

(C) Total number of chromosomes (autosomes and sex chromosomes) is same in both males and females.

(D) All eggs bear an additional X chromosome besides the autosomes.

Choose the correct answer from the options given below :

Frequency of recombination between gene pairs on same chromosome as a measure of the distance between genes to map their position on chromosome, was used for the first time by

The phenomenon of pleiotropism refers to

Which of the following statements are correct about Klinefelter’s Syndrome?

A. This disorder was first described by Langdon Down (1866).

B. Such an individual has overall masculine development. However, the feminine development is also expressed.

C. The affected individual is short statured.

D. Physical, psychomotor and mental development is retarded.

E. Such individuals are sterile.

Choose the correct answer from the options given below :

Broad palm with single palm crease is visible in a person suffering from-

Which one of the following symbols represents mating between relatives in human pedigree analysis?

Given below are two statements:

Statement I : Sickle cell anaemia and haemophilia are autosomal dominant traits.

Statement II : Sickle cell anaemia and haemophilia are disorders of the blood.

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

In meiosis, crossing over and exchange of genetic material between homologous chromosomes are catalyzed by the enzyme

The chromosomal theory of inheritance was proposed by

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?

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 :

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

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?

(a) Haemophilic son and haemophilic daughter.

(b) Haemophilic son and carrier daughter.

(c) Normal daughter and normal son.

(d) Normal son and haemophilic daughter.

Choose the most appropriate answer from the options given below:

XO type of sex determination can be found in :

Given below are two statements:

Statement I : Mendel studied seven pairs of contrasting traits in pea plants and proposed the Laws of Inheritance.

Statement II : Seven characters examined by Mendel in his experiment on pea plants were seed shape and colour, flower colour, pod shape and colour, flower position and stem height.

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

Which of the following occurs due to the presence of autosome linked dominant trait?

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : Mendel's law of independent assortment does not hold good for the genes that are located closely on the same chromosome.

Reason (R) : Closely located genes assort independently.

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

If a colour blind female marries a man whose mother was also colour blind, what are the chances of her progeny having colour blindness?

The recombination frequency between the genes a & c 5&, b & c is 15%, b & d is 9%, a & b is 20%, c & d is 25% and a & d is 29%. What will be the sequence of these genes on a linear chromosome?