BIOD 210 Genetics Module 2: Mendelian Genetics and Inheritance
2026/2027 UPDATE
1. Who is known as the father of modern genetics for his work with pea plants?
A. Gregor Mendel
B. Charles Darwin
C. James Watson
D. Francis Crick
Answer: A
Rationale: Gregor Mendel is recognized as the father of genetics for establishing the basic
laws of inheritance through his experiments with pea plants.
2. In genetics, what is the term used to describe the physical appearance or
observable traits of an organism?
A. Genotype
B. Allele
C. Phenotype
D. Locus
Answer: C
Rationale: Phenotype refers to the observable physical properties of an organism, which
are determined by its genetic makeup (genotype).
,3. What does the Law of Segregation state?
A. Alleles for different traits are inherited independently.
B. Dominant alleles always mask recessive alleles in every generation.
C. Each individual has two alleles for each gene which separate during gamete formation.
D. Genes are located on specific positions on chromosomes.
Answer: C
Rationale: Mendel’s Law of Segregation states that the two alleles for a heritable character
segregate during gamete formation and end up in different gametes.
4. An organism with two identical alleles for a particular gene is referred to as:
A. Heterozygous
B. Hemizygous
C. Homozygous
D. Dihybrid
Answer: C
Rationale: Homozygous organisms have two identical alleles (e.g., AA or aa) for a specific
gene.
5. If a plant with genotype ‘Tt’ is crossed with another ‘Tt’ plant, what is the
expected genotypic ratio of the offspring?
A. 3:1
B. 1:1
C. 9:3:3:1
D. 1:2:1
Answer: D
Rationale: A monohybrid cross of two heterozygotes (Tt x Tt) results in a genotypic ratio
of 1 TT : 2 Tt : 1 tt.
, 6. In a standard monohybrid cross between two heterozygotes, what is the
probability that an offspring will show the recessive phenotype?
A. 50%
B. 25%
C. 75%
D. 100%
Answer: B
Rationale: The probability of getting a recessive phenotype (tt) from a Tt x Tt cross is 1/4
or 25%.
7. Which tool is used to predict the possible genetic outcomes of a cross?
A. Pedigree Chart
B. Karyotype
C. Gel Electrophoresis
D. Punnett Square
Answer: D
Rationale: A Punnett Square is a diagram used to predict the genotypes of a particular
cross or breeding experiment.
8. A cross between an individual with an unknown genotype and a homozygous
recessive individual is called a:
A. Dihybrid cross
B. Monohybrid cross
C. Testcross
D. Backcross
Answer: C
Rationale: A testcross is performed to determine the genotype of an individual expressing
a dominant trait by crossing it with a homozygous recessive individual.
2026/2027 UPDATE
1. Who is known as the father of modern genetics for his work with pea plants?
A. Gregor Mendel
B. Charles Darwin
C. James Watson
D. Francis Crick
Answer: A
Rationale: Gregor Mendel is recognized as the father of genetics for establishing the basic
laws of inheritance through his experiments with pea plants.
2. In genetics, what is the term used to describe the physical appearance or
observable traits of an organism?
A. Genotype
B. Allele
C. Phenotype
D. Locus
Answer: C
Rationale: Phenotype refers to the observable physical properties of an organism, which
are determined by its genetic makeup (genotype).
,3. What does the Law of Segregation state?
A. Alleles for different traits are inherited independently.
B. Dominant alleles always mask recessive alleles in every generation.
C. Each individual has two alleles for each gene which separate during gamete formation.
D. Genes are located on specific positions on chromosomes.
Answer: C
Rationale: Mendel’s Law of Segregation states that the two alleles for a heritable character
segregate during gamete formation and end up in different gametes.
4. An organism with two identical alleles for a particular gene is referred to as:
A. Heterozygous
B. Hemizygous
C. Homozygous
D. Dihybrid
Answer: C
Rationale: Homozygous organisms have two identical alleles (e.g., AA or aa) for a specific
gene.
5. If a plant with genotype ‘Tt’ is crossed with another ‘Tt’ plant, what is the
expected genotypic ratio of the offspring?
A. 3:1
B. 1:1
C. 9:3:3:1
D. 1:2:1
Answer: D
Rationale: A monohybrid cross of two heterozygotes (Tt x Tt) results in a genotypic ratio
of 1 TT : 2 Tt : 1 tt.
, 6. In a standard monohybrid cross between two heterozygotes, what is the
probability that an offspring will show the recessive phenotype?
A. 50%
B. 25%
C. 75%
D. 100%
Answer: B
Rationale: The probability of getting a recessive phenotype (tt) from a Tt x Tt cross is 1/4
or 25%.
7. Which tool is used to predict the possible genetic outcomes of a cross?
A. Pedigree Chart
B. Karyotype
C. Gel Electrophoresis
D. Punnett Square
Answer: D
Rationale: A Punnett Square is a diagram used to predict the genotypes of a particular
cross or breeding experiment.
8. A cross between an individual with an unknown genotype and a homozygous
recessive individual is called a:
A. Dihybrid cross
B. Monohybrid cross
C. Testcross
D. Backcross
Answer: C
Rationale: A testcross is performed to determine the genotype of an individual expressing
a dominant trait by crossing it with a homozygous recessive individual.
