Q.1 Who is considered the father of genetics?
Charles Darwin
Gregor Mendel
Louis Pasteur
Francis Crick
Explanation - Gregor Mendel is known as the father of genetics for his experiments with pea plants, which established the basic principles of inheritance.
Correct answer is: Gregor Mendel
Q.2 Mendel used which plant for his genetic experiments?
Tomato
Wheat
Pea
Corn
Explanation - Mendel used pea plants (Pisum sativum) because they had easily observable traits and could be cross-pollinated.
Correct answer is: Pea
Q.3 Which of the following describes Mendel’s Law of Segregation?
Each allele pair segregates during gamete formation
Traits blend together in offspring
All traits are linked together
Dominant alleles disappear in the next generation
Explanation - Mendel’s Law of Segregation states that each individual has two alleles for a trait, which separate during gamete formation so each gamete receives one allele.
Correct answer is: Each allele pair segregates during gamete formation
Q.4 What is the typical phenotypic ratio in a Mendelian monohybrid cross?
1:2:1
3:1
9:3:3:1
2:1
Explanation - In a monohybrid cross with complete dominance, the phenotypic ratio of offspring is typically 3 dominant : 1 recessive.
Correct answer is: 3:1
Q.5 In Mendelian genetics, a capital letter usually represents a:
Recessive allele
Dominant allele
Homozygous recessive trait
Mutation
Explanation - Capital letters are used to denote dominant alleles, while lowercase letters represent recessive alleles.
Correct answer is: Dominant allele
Q.6 What does the term 'homozygous' mean?
Having two different alleles
Having identical alleles
Having one allele missing
Having three alleles
Explanation - Homozygous means having two identical alleles for a trait (e.g., AA or aa).
Correct answer is: Having identical alleles
Q.7 Which Mendelian law explains independent inheritance of two traits?
Law of Segregation
Law of Independent Assortment
Law of Dominance
Law of Blending
Explanation - The Law of Independent Assortment states that alleles of different genes assort independently during gamete formation.
Correct answer is: Law of Independent Assortment
Q.8 In a dihybrid cross, what is the expected phenotypic ratio?
3:1
9:3:3:1
1:1
1:2:1
Explanation - A dihybrid cross typically gives a 9:3:3:1 phenotypic ratio when two heterozygotes are crossed.
Correct answer is: 9:3:3:1
Q.9 Which of the following represents a heterozygous genotype?
AA
aa
Aa
AAA
Explanation - Heterozygous means having two different alleles, such as Aa.
Correct answer is: Aa
Q.10 What is a Punnett square used for?
To predict the traits of parents
To determine DNA sequences
To predict possible genotypes of offspring
To measure chromosome length
Explanation - A Punnett square helps predict the probability of offspring genotypes from parental crosses.
Correct answer is: To predict possible genotypes of offspring
Q.11 What term describes an observable trait?
Genotype
Phenotype
Allele
Genome
Explanation - Phenotype refers to the observable characteristics expressed in an organism, while genotype is the genetic makeup.
Correct answer is: Phenotype
Q.12 Which ratio indicates incomplete dominance in a monohybrid cross?
9:3:3:1
3:1
1:2:1
2:1
Explanation - Incomplete dominance results in a 1:2:1 ratio of phenotypes in heterozygotes, where blending occurs.
Correct answer is: 1:2:1
Q.13 What is codominance?
Only dominant allele is expressed
Only recessive allele is expressed
Both alleles are expressed equally
Alleles blend into an intermediate form
Explanation - Codominance occurs when both alleles contribute equally to the phenotype (e.g., AB blood group).
Correct answer is: Both alleles are expressed equally
Q.14 What are alternative forms of a gene called?
Chromosomes
Genotypes
Alleles
Phenotypes
Explanation - Alleles are alternative forms of the same gene located on homologous chromosomes.
Correct answer is: Alleles
Q.15 Which of these is an example of a recessive trait in humans?
Brown eyes
Widow’s peak
Attached earlobes
Freckles
Explanation - Attached earlobes are a commonly cited example of a recessive human trait.
Correct answer is: Attached earlobes
Q.16 If a homozygous tall pea plant (TT) is crossed with a homozygous short (tt), what will the offspring be?
All tall
All short
Half tall, half short
3 tall : 1 short
Explanation - Crossing TT with tt gives all heterozygous (Tt), which express the tall phenotype.
Correct answer is: All tall
Q.17 Which of these is NOT a trait Mendel studied in pea plants?
Seed shape
Flower color
Plant height
Leaf shape
Explanation - Mendel studied traits like seed shape, color, and plant height, but not leaf shape.
Correct answer is: Leaf shape
Q.18 In genetics, 'F1 generation' refers to:
First filial generation
Final generation
Foundational generation
Future generation
Explanation - The F1 generation is the first filial generation obtained by crossing two parent organisms.
Correct answer is: First filial generation
Q.19 What term describes the cross between two heterozygous organisms?
Monohybrid cross
Dihybrid cross
Test cross
Back cross
Explanation - A cross between two heterozygous organisms for one trait is called a monohybrid cross.
Correct answer is: Monohybrid cross
Q.20 In a test cross, an individual with a dominant phenotype is crossed with:
Homozygous dominant
Homozygous recessive
Heterozygous
Another unknown
Explanation - A test cross involves crossing with a homozygous recessive to determine the unknown genotype.
Correct answer is: Homozygous recessive
Q.21 If two heterozygous tall plants (Tt) are crossed, what is the genotypic ratio?
1:2:1
3:1
2:1
9:3:3:1
Explanation - The genotypic ratio from Tt × Tt is 1 TT : 2 Tt : 1 tt.
Correct answer is: 1:2:1
Q.22 Which of these represents a recessive homozygous genotype?
AA
Aa
aa
AaBb
Explanation - Recessive homozygous means both alleles are recessive, e.g., aa.
Correct answer is: aa
Q.23 Which scientist rediscovered Mendel’s work around 1900?
Hugo de Vries
Watson
Crick
Charles Darwin
Explanation - Hugo de Vries and others independently rediscovered Mendel’s work in 1900, validating his findings.
Correct answer is: Hugo de Vries
Q.24 Which type of inheritance pattern does blood group in humans follow?
Simple dominance
Codominance and multiple alleles
Incomplete dominance
Linked inheritance
Explanation - Human blood groups follow codominance (A and B alleles) and multiple alleles (A, B, O).
Correct answer is: Codominance and multiple alleles
Q.25 Which of the following supports Mendel’s Law of Independent Assortment?
Traits of one gene do not affect inheritance of another gene
Alleles separate during gamete formation
One allele masks another
Genes are blended together
Explanation - The Law of Independent Assortment states that the inheritance of one trait is independent of another (if located on different chromosomes).
Correct answer is: Traits of one gene do not affect inheritance of another gene