Question 1

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

Accepted Answer

Alleles for a character separate during gamete formation, so each gamete carries only one allele for each gene. $$A$$ and $$a$$ alleles segregate into different gametes.

Question 2

A man and a woman are both carriers for cystic fibrosis, a recessive disorder. What is the probability that their next child will have cystic fibrosis?

Accepted Answer

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

Question 3

Which of the following scenarios best illustrates the concept of pleiotropy?

Accepted Answer

A single gene mutation causes both sickle-shaped red blood cells and increased resistance to malaria.

Question 4

In Labrador retrievers, black coat color (B) is dominant to chocolate (b), and normal vision (N) is dominant to blindness (n). If two dogs with genotypes BbNn are crossed, what is the expected phenotypic ratio for coat color and vision in the offspring?

Accepted Answer

9 black, normal : 3 black, blind : 3 chocolate, normal : 1 chocolate, blind

Question 5

A woman with type AB blood and a man with type O blood have a child. What are the possible blood types of their child?

Accepted Answer

Type A or Type B

Question 6

Which of the following is an example of incomplete dominance?

Accepted Answer

A cross between red and white snapdragons produces pink flowers.

Question 7

A testcross is performed between a black Labrador retriever of unknown genotype and a chocolate Labrador (bb). If all offspring are black, what is the genotype of the black parent?

Accepted Answer

BB

Question 8

Which of the following statements about sex-linked inheritance is correct?

Accepted Answer

A male with a recessive allele on his X chromosome will express the trait.

Question 9

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 10

Which of the following best explains why linked genes do not follow Mendel’s law of independent assortment?

Accepted Answer

They are located close together on the same chromosome and tend to be inherited together.

Question 11

If a woman who is a carrier for red-green colorblindness (X$$^NX$^n) $$has children with a man with normal vision (X$$^NY$$), what is the probability that their son will be colorblind?

Accepted Answer

$$\frac{1}{2}$$

Question 12

Which of the following is an example of polygenic inheritance?

Accepted Answer

Human skin color, which is influenced by several genes and environmental factors.

Question 13

Which of the following best describes the chromosomal theory of inheritance?

Accepted Answer

Genes are located on chromosomes, and the behavior of chromosomes during meiosis accounts for inheritance patterns.

Question 14

A couple has a child with type O blood. The mother is type A and the father is type B. What are the possible genotypes of the parents?

Accepted Answer

Mother: I$$^Ai$$, Father: I$$^Bi$$

Question 15

Which of the following is a real-world example of codominance?

Accepted Answer

A person with type AB blood expresses both A and B antigens on their red blood cells.

Question 16

Which of the following statements about dominant and recessive alleles is correct?

Accepted Answer

A dominant allele masks the effect of a recessive allele in a heterozygote.

Question 17

A geneticist is studying a family with a history of a rare, lethal dominant disorder. If one parent is heterozygous for the disorder and the other is unaffected, what is the probability that their child will inherit the disorder?

Accepted Answer

$$\frac{1}{2}$$

Question 18

Which of the following best describes epigenetic inheritance?

Accepted Answer

The transmission of traits by mechanisms not directly involving changes in DNA sequence, such as chemical modifications to DNA or histones.

Question 19

Which of the following is a practical application of a Punnett square in medicine?

Accepted Answer

Predicting the probability that a child will inherit a genetic disorder from carrier parents.

Question 20

A genetic counselor is analyzing a pedigree for a family with a history of hemophilia, a sex-linked recessive disorder. Which of the following individuals is most likely to be affected?

Accepted Answer

A male with one X chromosome carrying the hemophilia allele.

Patterns of Inheritance: Mendelian Genetics and Beyond

Guida di studio - Domande di pratica

Study guide - Flashcard