Question 1

Which of the following statements best describes Mendel's Law of Segregation?

Accepted Answer

Paired hereditary factors separate randomly so that each gamete receives one factor.

Question 2

A pea plant with genotype Yy is crossed with another Yy plant. What is the probability that an offspring will have green seeds (yy)? Use a Punnett square to justify your answer.

Accepted Answer

$$\frac{1}{4}$$

Question 3

Which of the following is NOT a reason why Mendel chose pea plants for his experiments?

Accepted Answer

They have only one observable trait.

Question 4

In a dihybrid cross between two SsYy individuals, what is the probability of obtaining an offspring with the genotype ssYy?

Accepted Answer

$$\frac{1}{8}$$

Question 5

A testcross is performed between a plant with an unknown genotype showing the dominant phenotype and a homozygous recessive plant. If the unknown plant is heterozygous, what phenotypic ratio is expected in the offspring?

Accepted Answer

1 dominant : 1 recessive

Question 6

Which of the following best explains the product law in genetics?

Accepted Answer

The probability of two independent events occurring together is the product of their individual probabilities.

Question 7

If two heterozygous individuals for a recessive disease (Pp) have three children, what is the probability that all three children will be affected by the disease?

Accepted Answer

$$\frac{1}{64}$$

Question 8

Which of the following is a key feature of a dominant pattern of inheritance in a pedigree?

Accepted Answer

Affected individuals always have at least one affected parent.

Question 9

A cross between two true-breeding pea plants, one with round seeds (RR) and one with wrinkled seeds (rr), produces F1 offspring. What is the genotype and phenotype of the F1 generation?

Accepted Answer

Genotype: Rr; Phenotype: all round

Question 10

In a dihybrid cross (YyRr x YyRr), what is the expected phenotypic ratio in the F2 generation?

Accepted Answer

9:3:3:1

Question 11

Which of the following organisms is NOT considered a modern model genetic organism?

Accepted Answer

Homo sapiens

Question 12

A pedigree shows a trait that appears in every generation and affects both males and females equally. What is the most likely mode of inheritance?

Accepted Answer

Autosomal dominant

Question 13

Which of the following best describes the sum rule in probability as applied to genetics?

Accepted Answer

The probability of one of two mutually exclusive events occurring is the sum of their probabilities.

Question 14

If a plant with genotype SsYy is crossed with a plant with genotype ssyy, what proportion of the offspring are expected to have the genotype SsYy?

Accepted Answer

$$\frac{1}{4}$$

Question 15

Which of the following is a misconception about Mendel's findings?

Accepted Answer

Traits can blend together in the offspring.

Question 16

A couple, both heterozygous for cystic fibrosis (a recessive disorder), want to know the probability that their first child will be unaffected. What is the probability?

Accepted Answer

$$\frac{3}{4}$$

Question 17

Which of the following best explains why large sample sizes are important in genetic experiments?

Accepted Answer

They reduce the effect of random sampling error.

Question 18

Which of the following is a representative dominant human trait?

Accepted Answer

Huntington disease

Question 19

In a pedigree, which symbol represents a female who is a heterozygous carrier for a recessive trait?

Accepted Answer

A half-filled circle

Question 20

Which of the following best describes the concept of independent assortment?

Accepted Answer

Genes for different traits segregate independently during gamete formation.

Mendelian Genetics: Principles, Experiments, and Applications

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