1. Mendel’s first law is also called:
A) Law of Independent Assortment
B) Law of Segregation ✅
C) Law of Dominance
D) Law of Multiple Alleles
In a monohybrid cross of Aa × Aa, the genotypic ratio is:
A) 1:2:1 ✅
B) 3:1
C) 1:1
D) 2:1
Mendel’s experiments were performed on:
A) Maize
B) Garden Pea ✅
C) Wheat
D) Fruit Fly
The principle stating that genes for different traits segregate independently is:
A) Law of Dominance
B) Law of Independent Assortment ✅
C) Law of Segregation
D) Law of Recombination
In a dihybrid cross (AaBb × AaBb), the phenotypic ratio is:
A) 9:3:3:1 ✅
B) 1:2:1
C) 3:1
D) 2:2:1:1
Which of the following is a test cross?
A) Aa × Aa
B) AA × aa ✅
C) Aa × AA
D) Aa × Aa
Incomplete dominance results in:
A) Blending of traits ✅
B) Expression of both alleles equally
C) Only dominant trait appears
D) Only recessive trait appears
Codominance occurs when:
A) One allele masks the other
B) Both alleles are expressed equally ✅
C) Traits blend
D) Traits segregate
Mendel observed traits that:
A) Show continuous variation
B) Were discrete and easily distinguishable ✅
C) Depended on environment
D) Were polygenic
In a cross Aa × Aa, the probability of offspring being homozygous dominant is:
A) 1/2
B) 1/4 ✅
C) 1/8
D) 3/4
The law of segregation applies during:
A) Fertilization
B) Gamete formation ✅
C) Mitosis
D) Gene recombination
A monohybrid cross involves:
A) Two traits
B) One trait ✅
C) Multiple alleles
D) Sex-linked traits
Mendel’s pea plants had:
A) Dioecious flowers
B) Perfect flowers ✅
C) Only male flowers
D) Only female flowers
The genotype of an individual showing dominant phenotype but heterozygous is:
A) AA
B) Aa ✅
C) aa
D) A–
Law of independent assortment applies only if:
A) Genes are linked
B) Genes are on different chromosomes ✅
C) Genes are on the same chromosome
D) Genes are recessive
If two heterozygotes are crossed, the proportion of heterozygous offspring is:
A) 1/4
B) 1/2 ✅
C) 3/4
D) 1/8
Mendel’s pea plant traits were:
A) Polygenic
B) Qualitative ✅
C) Quantitative
D) Environmental
In a dihybrid test cross (AaBb × aabb), the phenotypic ratio is:
A) 9:3:3:1
B) 1:1:1:1 ✅
C) 3:1
D) 2:1:1
The segregation of alleles is due to:
A) Fertilization
B) Crossing over
C) Separation of homologous chromosomes during meiosis ✅
D) Mutation
Which is an example of incomplete dominance?
A) Red × White flowers giving pink flowers ✅
B) Blood group inheritance
C) Mendel’s pea shape
D) Sex-linked traits
A dihybrid cross between AaBb × AABB produces the ratio of:
A) 1:1:1:1
B) 1:1 ✅
C) 2:1
D) 9:3:3:1
Mendel’s second law is known as:
A) Law of Segregation
B) Law of Dominance
C) Law of Independent Assortment ✅
D) Law of Probability
In a monohybrid cross of AA × aa, all offspring are:
A) Homozygous dominant
B) Heterozygous ✅
C) Homozygous recessive
D) Mixed
The observable trait of an organism is its:
A) Genotype
B) Phenotype ✅
C) Gamete
D) Allele
Which of the following is not Mendelian inheritance?
A) Codominance
B) Incomplete dominance
C) Polygenic inheritance ✅
D) Monohybrid inheritance
A cross of two heterozygotes (Aa × Aa) gives what proportion of recessive offspring?
A) 1/2
B) 1/4 ✅
C) 3/4
D) 2/3
The term “allele” refers to:
A) Different forms of a gene ✅
B) Chromosome
C) Gamete
D) Trait
Mendel’s F2 generation phenotypic ratio for monohybrid cross:
A) 1:1
B) 3:1 ✅
C) 9:3:3:1
D) 2:1
In codominance, the heterozygote shows:
A) Dominant phenotype only
B) Recessive phenotype only
C) Both parental phenotypes ✅
D) Blended phenotype
If a red flower (RR) is crossed with white (rr), the F1 is:
A) All red ✅
B) All white
C) Pink
D) Mixed red and white
In Mendelian terms, “homozygous” means:
A) Different alleles
B) Same alleles ✅
C) Dominant allele present
D) Recessive allele present
A heterozygous organism crossed with homozygous recessive is:
A) Monohybrid cross
B) Test cross ✅
C) Dihybrid cross
D) Reciprocal cross
Mendel concluded that traits are:
A) Blended
B) Controlled by discrete units ✅
C) Randomly appearing
D) Environment-dependent
If two heterozygotes are crossed, the probability of homozygous recessive offspring is:
A) 1/4 ✅
B) 1/2
C) 3/4
D) 1/8
Mendel used true-breeding plants to ensure:
A) Hybrid vigor
B) Pure lines ✅
C) Environmental effect
D) Genetic recombination
Law of Dominance states:
A) Dominant allele masks recessive ✅
B) Both alleles expressed
C) Traits blend
D) Alleles segregate
Independent assortment results in:
A) New combinations of alleles ✅
B) Mutation
C) Dominance
D) Segregation
A dihybrid cross involving AaBb × AaBb shows genotypic ratio:
A) 9:3:3:1
B) 1:2:1:2:4:2:1:2:1 ✅
C) 3:1
D) 1:1
Mendel’s experiments did not consider:
A) Discrete traits
B) Environmental factors ✅
C) True-breeding plants
D) Replication
Sex-linked traits follow:
A) Mendelian inheritance only
B) Non-Mendelian inheritance ✅
C) Independent assortment only
D) Segregation
In a tri-hybrid cross, number of genotypic combinations:
A) 8
B) 27 ✅
C) 16
D) 4
The ratio 3:1 in monohybrid cross refers to:
A) Genotype
B) Phenotype ✅
C) Gamete types
D) Allele frequency
Mendel’s principle of segregation was based on:
A) Observing F1 hybrids ✅
B) DNA sequencing
C) Chromosome painting
D) Allele mutation
A cross between two pink flowers showing incomplete dominance yields:
A) 1 red: 2 pink: 1 white ✅
B) 3 red: 1 white
C) 1 pink: 1 red
D) 2 red: 2 pink
Which cross produces 1:1 phenotypic ratio?
A) Aa × Aa
B) Aa × aa ✅
C) AA × aa
D) AA × Aa
46. Mendelian inheritance assumes:
A) Multiple genes per trait
B) Each trait controlled by a single gene ✅
C) Environment independent
47. A heterozygous tall pea plant (Tt) is crossed with a short plant (tt). The proportion of tall offspring is:
A) 1/4
B) 1/2 ✅
C) 3/4
D) 1/3
In Mendelian terms, “recessive” allele expresses its trait:
A) In heterozygote
B) Only in homozygote ✅
C) Always
D) Never
Mendel’s principle of independent assortment is illustrated by:
A) Monohybrid cross
B) Dihybrid cross ✅
C) Test cross
D) Reciprocal cross
If a cross yields a 9:3:3:1 ratio, it is:
A) Monohybrid
B) Dihybrid ✅
C) Trihybrid
D) Test cross
Mendel used 7 traits in peas because:
A) They were polygenic
B) They were discrete and easily observable ✅
C) They were quantitative
D) They were environmentally influenced
In a monohybrid cross, the gametes produced by Aa are:
A) A only
B) a only
C) A and a ✅
D) Aa
A test cross is used to determine:
A) Phenotype
B) Genotype ✅
C) Allele frequency
D) Mutation
Mendel’s F1 generation of monohybrid cross shows:
A) Both parental traits
B) Dominant trait only ✅
C) Recessive trait only
D) Blended traits
Incomplete dominance differs from Mendelian dominance because:
A) Traits segregate
B) Heterozygote shows intermediate phenotype ✅
C) Only dominant trait expressed
D) Only recessive trait expressed
In a dihybrid cross AaBb × AaBb, the number of gamete types is:
A) 2
B) 4 ✅
C) 8
D) 16
The alleles that segregate during gamete formation are:
A) Dominant only
B) Recessive only
C) Both alleles of a gene ✅
D) Linked genes
Mendel observed that hybrid offspring resemble:
A) Both parents equally
B) Only one parent (dominant) ✅
C) Blended traits
D) Random traits
In a cross Aa × Aa, the probability of homozygous dominant offspring is:
A) 1/2
B) 1/4 ✅
C) 1/8
D) 3/4
Mendel’s principle of dominance explains:
A) Segregation of alleles
B) Blending of traits
C) Expression of one allele over the other ✅
D) Independent assortment
In codominance, blood group AB is an example of:
A) Complete dominance
B) Incomplete dominance
C) Both alleles expressed ✅
D) Recessive trait
In a monohybrid cross Aa × aa, the phenotypic ratio is:
A) 1:1 ✅
B) 3:1
C) 1:2:1
D) 9:3:3:1
Mendel’s law of segregation is due to:
A) Chromosome replication
B) Separation of homologous chromosomes in meiosis ✅
C) Fertilization
D) Recombination
Dihybrid cross can produce offspring phenotypic ratio of:
A) 3:1
B) 9:3:3:1 ✅
C) 1:1
D) 1:2:1
Mendelian inheritance is based on:
A) Quantitative traits
B) Single gene controlling a trait ✅
C) Polygenic traits
D) Environmental effects
In a monohybrid cross, 3:1 ratio refers to:
A) Genotype
B) Phenotype ✅
C) Gametes
D) Alleles
Mendel’s pea plant seeds were:
A) Round or wrinkled ✅
B) Spotted or striped
C) Polymorphic
D) Random
If a heterozygote is crossed with homozygous recessive, what is the genotypic ratio?
A) 1:1 ✅
B) 1:2:1
C) 3:1
D) 9:3:3:1
Law of independent assortment fails in case of:
A) Linked genes ✅
B) Dominant alleles
C) Recessive alleles
D) Monohybrid traits
Which of the following is not a Mendelian trait?
A) Blood groups
B) Eye color (continuous trait) ✅
C) Seed shape
D) Flower color
In a dihybrid cross, if AaBb × aabb is performed, the expected phenotypic ratio is:
A) 9:3:3:1
B) 1:1:1:1 ✅
C) 3:1
D) 2:1:1
The main reason Mendel selected pea plants was:
A) Short life cycle ✅
B) Polyploidy
C) Cross-pollination difficulty
D) Large genome
In incomplete dominance, the F2 generation ratio is:
A) 3:1
B) 1:2:1 ✅
C) 9:3:3:1
D) 1:1
If two heterozygous tall plants (Tt) are crossed, probability of short offspring is:
A) 1/2
B) 1/4 ✅
C) 3/4
D) 2/3
In codominance, heterozygotes display:
A) Recessive phenotype
B) Dominant phenotype
C) Both parental phenotypes ✅
D) Blended traits
The ratio 1:2:1 in monohybrid F2 generation refers to:
A) Phenotype
B) Genotype ✅
C) Gametes
D) Alleles
Mendel’s law of segregation applies to:
A) Homozygous only
B) Heterozygous only
C) Both heterozygous and homozygous ✅
D) Sex-linked traits
Mendel’s work remained unrecognized until:
A) 1880s ✅
B) 1850s
C) 1900s
D) 1920s
When a dihybrid AaBb × AaBb is crossed, the proportion of double recessive offspring (aabb) is:
A) 1/16 ✅
B) 1/4
C) 3/16
D) 9/16
Mendel avoided self-pollination by:
A) Bagging flowers ✅
B) Using chemicals
C) Cross-breeding only
D) Cutting stems
The term “F1 generation” refers to:
A) Parental
B) First filial ✅
C) Second filial
D) Third filial
Mendel’s pea plant height trait is:
A) Polygenic
B) Monogenic ✅
C) Sex-linked
D) Environmental
If a heterozygote is crossed with homozygous dominant, the proportion of homozygous dominant offspring is:
A) 1/2
B) 1/4
C) 1 ✅
D) 3/4
Mendel observed seven pairs of contrasting traits. One is:
A) Seed color ✅
B) Flower fragrance
C) Leaf shape
D) Stem thickness
In a tri-hybrid cross, the total number of possible gametes from AaBbCc is:
A) 4
B) 6
C) 8 ✅
D) 12
In Mendelian inheritance, F2 generation exhibits:
A) Only dominant traits
B) Reappearance of recessive traits ✅
C) Blended traits
D) Random mutation
The 3:1 phenotypic ratio occurs in:
A) Dihybrid cross
B) Monohybrid cross ✅
C) Trihybrid cross
D) Polygenic inheritance
Mendel’s experiments proved:
A) Traits blend in hybrids
B) Traits controlled by discrete units (genes) ✅
C) Environment solely determines traits
D) Alleles mutate randomly
In a dihybrid cross AaBb × AaBb, proportion of offspring showing both dominant traits (A_B_) is:
A) 9/16 ✅
B) 3/16
C) 1/16
D) 1/4
Which of the following crosses is an example of test cross?
A) Aa × Aa
B) Aa × aa ✅
C) AA × Aa
D) AA × aa
91. Mendel’s law of segregation ensures:
A) Equal segregation of alleles into gametes ✅
B) Unequal recombination
C) Continuous variation
D
92. In a monohybrid F2 generation, the ratio of heterozygotes to homozygotes is:
A) 1:1
B) 2:1 ✅
C) 3:1
D) 1:2
Mendel chose pea plants because they:
A) Have long generation time
B) Exhibit easy cross-pollination ✅
C) Show polygenic traits
D) Have complex genomes
Which is true for a dihybrid cross involving independent assortment?
A) Alleles segregate together
B) Each allele pair segregates independently ✅
C) Only dominant alleles are passed
D) Recessive alleles are masked
The cross AaBb × AaBb produces a phenotypic ratio of:
A) 3:1
B) 9:3:3:1 ✅
C) 1:2:1
D) 1:1
In incomplete dominance, the F1 phenotype is:
A) Same as one parent
B) Intermediate between parents ✅
C) Dominant only
D) Recessive only
Mendel’s law of segregation predicts that:
A) Alleles remain together in gametes
B) Each gamete receives one allele of each gene ✅
C) Dominant alleles are favored
D) Only recessive alleles segregate
In a cross between red (RR) and white (rr) snapdragon flowers, F1 is pink. The F2 ratio will be:
A) 3 red: 1 white
B) 1 red: 2 pink: 1 white ✅
C) 1 red: 1 pink
D) 2 red: 2 pink
In a dihybrid cross AaBb × Aabb, the proportion of offspring with genotype AaBb is:
A) 1/4 ✅
B) 1/2
C) 1/8
D) 3/4
100. Mendel’s experiments demonstrated that:
A) Traits blend in hybrids
B) Hereditary units are discrete (genes) ✅
C) Environment determines inheritance
D) All traits are dominant