Principles of Inheritance and Variation

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:

[NEET 2024]

The sixth mutant codon of beta globin gene causing polymerization of Haemoglobin and change in RBC shape is ______.

[NEET 2026]

Given below are two statements:

Statement I: Down's syndrome is caused by the absence of one of the X-chromosomes.

Statement II: Turner's syndrome is caused by the presence of an additional copy of the chromosomes.

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

[Re-NEET 2026]

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 most appropriate answer from the options given below:

[Re-NEET 2024]

What is the probability of having children with 'O' blood group, where both mother and father are heterozygous for 'A' and 'B' blood group, respectively?

[NEET 2026]

Given below are two statements:
Statement I : Failure of segregation of chromatids during cell cycle resulting in the gain or loss of whole set of chromosome in an organism is known as aneuploidy.
Statement II : Failure of cytokinesis after anaphase stage of cell division results in the gain or loss of a chromosome is called polyploidy.
In the light of the above statements, choose the most appropriate answer from the options given below:

[Re-NEET 2024]

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.

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

[NEET 2024]

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

[NEET 2024]

Which one of the following disorders is caused by the substitution of Glutamic acid (Glu) by Valine (Val) at the sixth position of the beta globin chain of the haemoglobin molecule?

[NEET 2026]

In a population of a grasshopper species, the chromosome number of some members is 23 and some other members possess 24 chromosomes. The 23 and 24 chromosome-bearing members in this species are _______ .

[NEET 2026]

Match List I with List II :

List I List II
A. Down's syndrome I. \({11}^{\text{th }}\) chromosome
B. \(\alpha\)-Thalassemia II. ' X ' chromosome
C. \(\beta\)-Thalassemia III. \({21}^{\text{st }}\) chromosome
D. Klinefelter's syndrome IV. \({16}^{\text{th }}\) chromosome
Choose the correct answer from the options given below:

[NEET 2024]

Genes R and Y follow independent assortment. If RRYY produce round yellow seeds and rryy produce wrinkled green seeds, what will be the phenotypic ratio of the \({\mathrm{F}}_{2}\) generation?

[NEET 2025]

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:

[NEET 2024]

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:

[Re-NEET 2024]

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 most appropriate answer from the options given below:

[Re-NEET 2024]

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:

[Re-NEET 2024]

What is the pattern of inheritance for polygenic trait?

[NEET 2025]

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

Assertion A: In an experiment, Mendel observed that the F₁ progeny plants are all tall and none are dwarf.

Reason R: Stem height is a contrasting trait, with tall being dominant and dwarf being recessive.

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

[Re-NEET 2026]

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

[NEET 2024]

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.

[Re-NEET 2024]

For a person with blood group 'O', which of the following is not a possible combination of parents' blood group genotypes?

[Re-NEET 2026]

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

[NEET 2024]

Which of the following statements are true with reference to the sex-determination in honeybees?
A. An offspring formed from the union of a sperm and an egg, develops as a female (queen or worker).
B. An unfertilized egg develops as a male by parthenogenesis.
C. A male has half the number of chromosomes than that of a female.
D. Males produce sperms by meiosis.
E. Honeybees have a haplodiploid sex-determination system.
Choose the correct answer from the options given below:

[NEET 2026]

The best example for pleiotropy is

[Re-NEET 2020]

Chromosomal theory of inheritance was proposed by

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

Experimental verification of the chromosomal theory of inheritance was done by

[NEET 2020]

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:

[NEET 2023]

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

[NEET 2023]

Identify the wrong statement with reference to the gene \( I \) that controls ABO blood groups.

[NEET 2020]

The production for gametes by the parents, formation of zygotes, the \(\mathrm{F}_1\) and \(\mathrm{F}_2\) plants, can be understood from a diagram called

The number of contrasting characters studied by Mendel for his experiments was

The best example for pleiotropy is

The phenomenon of pleiotropism refers to

The number of contrasting characters studied by Mendel for his experiments was:

[Re-NEET 2020]

The production of gametes by parents, formation of zygote, the \( f_{1} \) and \( f_{2} \) plants can be understood from a diagram called:

[NEET 2021]

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

[NEET 2021]

Identify the wrong statement with reference to the gene ' \(I\) ' that controls ABO blood groups

Experimental verification of the chromosomal theory of inheritance was done by

Match List-I with List-II :

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

Select the correct match.

Match List-I with List-II.

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

[NEET 2023]

The phenomenon of pleiotropism refers to

[NEET 2023]

Chromosomal theory of inheritance was proposed by

[Re-NEET 2020]