Question 1

Which of the following best describes the difference between chromatin and chromosomes in terms of gene activity?

Accepted Answer

Genes are active in the chromatin (strand) form and inactive when DNA is in the chromosome (compact) form.

Question 2

A child inherits a recessive genetic disorder from parents who do not show symptoms of the disease. Which of the following best explains this scenario?

Accepted Answer

Both parents are carriers of the recessive allele.

Question 3

Which of the following is an example of a sex-linked trait?

Accepted Answer

Red-green color vision deficiency

Question 4

A male child is diagnosed with hemophilia, an X-linked recessive disorder. His mother is not affected but his maternal grandfather was. What is the most likely genotype of the mother?

Accepted Answer

Heterozygous (carrier)

Question 5

Which process increases genetic variation by exchanging segments between homologous chromosomes during meiosis?

Accepted Answer

Crossing-over

Question 6

A karyotype analysis reveals a male with two X chromosomes and one Y chromosome (XXY). Which syndrome does this individual most likely have?

Accepted Answer

Klinefelter syndrome

Question 7

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

Accepted Answer

Different genes independently separate from one another when reproductive cells are forming.

Question 8

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 9

Which of the following genetic disorders is caused by trisomy of chromosome 21?

Accepted Answer

Down syndrome

Question 10

Which of the following best explains why some people with a disease-causing gene do not develop the disease or have a milder version?

Accepted Answer

Polygenic inheritance and environmental factors can influence gene expression.

Question 11

A woman with genotype $$X^N X^n ($$where $$N is $$normal and $$n is $$colorblind) and a man with genotype $$X^N Y$$ have a child. What is the probability that their son will be colorblind?

Accepted Answer

$$0.25$$

Question 12

Which of the following is a method used to collect fetal cells for genetic testing by inserting a needle through the uterine wall?

Accepted Answer

Amniocentesis

Question 13

Which of the following best describes gene therapy?

Accepted Answer

Manipulating genes to cure or treat genetic problems.

Question 14

A child is born with only one X chromosome and no second sex chromosome. Which disorder does this child most likely have?

Accepted Answer

Turner syndrome

Question 15

Which of the following is an example of a disease caused by a recessive autosomal gene?

Accepted Answer

Cystic fibrosis

Question 16

Which of the following best describes the role of epigenetics in genetic disease?

Accepted Answer

Epigenetics describes how environmental factors can turn genes on or off without changing the DNA sequence.

Question 17

Which of the following is a tool used to determine the probability of inheriting genetic traits by combining parental alleles?

Accepted Answer

Punnett square

Question 18

A genetic mutation can be caused by all of the following EXCEPT:

Accepted Answer

Balanced diet

Question 19

Which of the following statements about the Human Genome Project is correct?

Accepted Answer

It identified about 20,000-25,000 genes in the human genome.

Question 20

Which of the following best describes codominance?

Accepted Answer

Both alleles are expressed equally in the phenotype.

Genetics and Genetic Disease: Mechanisms, Inheritance, and Clinical Implications

Study Guide - Practice Questions

Study Guide - Flashcards