Q: Which equation correctly represents the rule of multiplication for independent events in genetics?

$$P(A \times B) = P(A) \times P(B)$$

Question 1

Which of the following best describes Mendel's law of segregation?

Accepted Answer

Each individual has two factors for each trait, which separate during gamete formation so each gamete contains only one factor from each pair.

Question 2

A pea plant with genotype $$Gg ($$green pod, heterozygous) is crossed with a plant with genotype $$gg ($$yellow pod, homozygous recessive). What is the expected phenotypic ratio of the offspring?

Accepted Answer

$$1$$ green : $$1$$ yellow

Question 3

In a dihybrid cross between two plants with genotype $$TtGg$$, what is the expected phenotypic ratio among the offspring according to Mendel's law of independent assortment?

Accepted Answer

$$9:3:3:1$$

Question 4

Which statement about alleles is correct?

Accepted Answer

Alleles are different forms of a gene located at the same locus on homologous chromosomes.

Question 5

A pedigree shows a genetic disorder that appears in children even though neither parent is affected. What is the most likely mode of inheritance?

Accepted Answer

Autosomal recessive

Question 6

Which of the following disorders is caused by a single base change in the globin gene, resulting in sickle-shaped red blood cells?

Accepted Answer

Sickle-cell disease

Question 7

If a person with genotype $$Aa ($$heterozygous for a dominant disorder) has children with a person who is $$aa ($$homozygous recessive), what is the probability that their child will be affected by the disorder?

Accepted Answer

$$0.5$$

Question 8

Which of the following best explains incomplete dominance?

Accepted Answer

The heterozygote has an intermediate phenotype between the two homozygotes.

Question 9

A woman with genotype $$I^A I^B$$ for the ABO blood group marries a man with genotype $$ii. $$What are the possible blood types of their children?

Accepted Answer

A and B only

Question 10

Which of the following is an example of a polygenic trait in humans?

Accepted Answer

Height

Question 11

A male inherits an X-linked recessive disorder. Which parent must have passed the affected allele?

Accepted Answer

His mother

Question 12

Which equation correctly represents the rule of multiplication for independent events in genetics?

Accepted Answer

$$P(A 	imes B) = P(A) 	imes P(B)$$

Question 13

Which of the following best describes pleiotropy?

Accepted Answer

A single gene affects multiple, seemingly unrelated traits.

Question 14

In a two-trait testcross of a fruit fly with genotype $$L G g ($$long wings, gray body, black allele), what offspring ratio would indicate the fly is a dihybrid?

Accepted Answer

$$1:1:1:1$$

Question 15

Which of the following is true about gene linkage?

Accepted Answer

Linked genes are located on the same chromosome and tend to be inherited together.

Question 16

A pedigree shows that all daughters of affected males have a certain trait, but sons do not. What is the most likely inheritance pattern?

Accepted Answer

X-linked dominant

Question 17

Which of the following is a real-world example of incomplete dominance in humans?

Accepted Answer

Familial hypercholesterolemia

Question 18

Which statement about environmental influences on phenotype is correct?

Accepted Answer

Environmental factors can affect the expression of polygenic traits, such as skin color.

Question 19

If two heterozygous parents ($$Aa) $$for an autosomal recessive disorder have a child, what is the probability that the child will be affected?

Accepted Answer

$$0.25$$

Question 20

Which of the following best explains codominance in the ABO blood group system?

Accepted Answer

Both $$I^A$$ and $$I^B$$ alleles are expressed equally in the heterozygote, resulting in AB blood type.

Patterns of Inheritance: Mendel’s Laws and Beyond

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