Question 1

Which of the following best describes the sliding filament mechanism in skeletal muscle contraction?

Accepted Answer

Myosin heads bind to actin, pulling actin filaments toward the center of the sarcomere, causing the sarcomere to shorten.

Question 2

A patient is unable to generate enough body heat and is diagnosed with a disorder affecting the primary system responsible for heat production. Which system is most likely affected?

Accepted Answer

Muscular system

Question 3

During inhalation, which of the following best describes the change in pressure inside the lungs?

Accepted Answer

Lung pressure decreases below atmospheric pressure, causing air to flow in.

Question 4

Which of the following best explains the function of the intercostal muscles during breathing?

Accepted Answer

They contract during inhalation to elevate the rib cage, increasing thoracic volume.

Question 5

Which of the following is the correct order of events leading to muscle contraction after a nerve impulse?

Accepted Answer

Release of acetylcholine → depolarization of sarcolemma → release of calcium ions → sliding of actin and myosin filaments

Question 6

Which of the following best describes the function of enzymes in the human digestive system?

Accepted Answer

They chemically catalyze the breakdown of macromolecules into absorbable units.

Question 7

A person has a mutation in the gene encoding for a digestive enzyme produced in the pancreas. Which macromolecule's digestion is most likely to be impaired?

Accepted Answer

All of the above

Question 8

Which of the following best explains why the small intestine has a large surface area?

Accepted Answer

To maximize nutrient absorption

Question 9

Which of the following statements about the Law of Segregation is correct?

Accepted Answer

Each gamete receives only one allele of each gene during meiosis.

Question 10

A woman with genotype $$X^N X^n ($$where $$N is $$normal and $$n is a $$recessive X-linked disorder) has children with a man who is $$X^N Y. $$What is the probability that their son will have the disorder?

Accepted Answer

$$0.25$$

Question 11

Which of the following best describes codominance?

Accepted Answer

Both alleles are fully expressed in the phenotype.

Question 12

Which of the following is an example of polygenic inheritance?

Accepted Answer

Height in humans

Question 13

A karyotype is used to:

Accepted Answer

Visualize and count the number of chromosomes in a cell.

Question 14

Which of the following best explains why some recessive genetic disorders remain prevalent in human populations?

Accepted Answer

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

Question 15

Which of the following best describes the difference between isotonic and isometric muscle contractions?

Accepted Answer

Isotonic contractions change muscle length, while isometric contractions do not change muscle length.

Question 16

Which of the following best describes the function of the diaphragm in respiration?

Accepted Answer

It contracts to increase thoracic volume during inhalation.

Question 17

Which of the following is a direct result of nondisjunction during meiosis?

Accepted Answer

Gametes with abnormal numbers of chromosomes

Question 18

Which of the following best explains the significance of 'My Plate' in human nutrition?

Accepted Answer

It provides a visual guide for balanced food group intake.

Question 19

Which of the following best describes the function of peristalsis in the digestive system?

Accepted Answer

It moves food through the digestive tract via coordinated muscle contractions.

Question 20

A child is born with a genotype $$AaBb$$ for two genes located on different chromosomes. According to the Law of Independent Assortment, what is the probability that a gamete will contain the $$ab$$ combination?

Accepted Answer

$$0.25$$

Human Biology Exam 2 Study Guide: Muscular, Respiratory, Digestive Systems & Genetics

Study Guide - Practice Questions

Study Guide - Flashcards