Question 1

Which of the following best describes the molecular structure of a gene?

Accepted Answer

A segment of DNA that codes for a specific protein or functional RNA.

Question 2

A human cell contains 46 chromosomes. What is the term for the complete set of genetic material in this cell?

Accepted Answer

Genome

Question 3

If a child inherits one dominant allele ($$A) $$and one recessive allele ($$a) $$for a trait, what is the genotype and expected phenotype?

Accepted Answer

Genotype: $$Aa$$, Phenotype: Dominant trait expressed

Question 4

Which of the following best explains the Law of Segregation?

Accepted Answer

Each individual has two alleles for each gene, and these alleles separate during gamete formation.

Question 5

A karyotype is used in clinical genetics to:

Accepted Answer

Visualize the number and structure of chromosomes in a cell.

Question 6

Which scenario best illustrates incomplete dominance?

Accepted Answer

A cross between red-flowered ($$RR) $$and white-flowered ($$rr) $$plants produces pink-flowered ($$Rr) $$offspring.

Question 7

Which of the following best describes codominance?

Accepted Answer

Both alleles are fully expressed in the phenotype, such as $$AB$$ blood type.

Question 8

Polygenic inheritance is characterized by:

Accepted Answer

Multiple genes contributing to a single trait, such as human height.

Question 9

Which of the following is an example of environmental impact on phenotypic expression?

Accepted Answer

Identical twins raised in different environments showing differences in intelligence.

Question 10

Linked genes are most likely to:

Accepted Answer

Be inherited together because they are located close to each other on the same chromosome.

Question 11

During meiosis, new combinations of alleles can arise due to:

Accepted Answer

Crossing over between homologous chromosomes.

Question 12

Sex-linked genes are typically found on:

Accepted Answer

The X or Y chromosomes.

Question 13

Nondisjunction during meiosis can result in:

Accepted Answer

Gametes with abnormal numbers of chromosomes, such as trisomy 21.

Question 14

A Punnett Square is used to:

Accepted Answer

Predict the probability of offspring genotypes and phenotypes from parental crosses.

Question 15

Which of the following best describes a homozygous genotype?

Accepted Answer

Both alleles for a gene are identical, such as $$AA or$$ $$aa.$$

Question 16

Why are some recessive disorders, such as cystic fibrosis, still prevalent in human populations?

Accepted Answer

Carriers (heterozygotes) do not express the disorder and can pass the allele to offspring.

Question 17

Which of the following best illustrates the Law of Independent Assortment?

Accepted Answer

Alleles for different genes are distributed independently during gamete formation.

Question 18

A person with genotype $$Bb$$ for a gene where $$B is $$dominant and $$b is $$recessive will express which phenotype?

Accepted Answer

Dominant phenotype

Question 19

Which of the following is a real-world example of a lethal dominant allele disorder?

Accepted Answer

Huntington's disease

Question 20

If a male inherits an X-linked recessive allele for color blindness, what is the expected outcome?

Accepted Answer

He will express color blindness because he has only one X chromosome.

Step-by-Step Guidance for Human Genetics and Inheritance Study Questions

Study Guide - Practice Questions