Cardiac Muscle Structure and Function Quiz

Test your knowledge on cardiac muscle cells, contraction, ions, hormones, and more in this cardiac physiology quiz.

Practice Learn Test

What is the primary function of cardiac muscle tissue?

To contract and pump blood throughout the body.

To support and protect organs.

To facilitate voluntary movements.

To produce and secrete hormones.

Which statement best describes the structure of cardiac muscle cells?

They are multinucleated with striations.

They are mononucleated with no striations.

They are uninucleated with intercalated discs.

They are binucleated with smooth appearance.

Which ion is primarily responsible for initiating contraction in cardiac muscle cells?

Sodium (Na+)

Potassium (K+)

Calcium (Ca2+)

Chloride (Cl-)

What is the role of intercalated discs in cardiac muscle tissue?

To store energy reserves.

To facilitate communication between cells.

To regulate the flow of blood.

To maintain cell shape.

Which of the following best describes the energy source for cardiac muscle contraction?

ATP generated from glycolysis

ATP generated from oxidative phosphorylation

Glucose directly

Fatty acids

Which neurotransmitter is primarily responsible for slowing the heart rate?

Acetylcholine

Norepinephrine

Dopamine

Serotonin

Which of the following factors can increase the contractility of cardiac muscle?

Decreased levels of calcium ions

Sympathetic nervous system stimulation

Increased levels of potassium ions

Parasympathetic nervous system stimulation

Which hormone increases heart rate and force of contraction?

Insulin

Glucagon

Epinephrine

Aldosterone

What is the refractory period in cardiac muscle?

The period of relaxation after contraction.

The time during which the heart cannot contract again.

The period when the heart is most susceptible to arrhythmias.

The time it takes for the heart to pump blood to the body.

#10

Which of the following is NOT a characteristic of cardiac muscle cells?

Involuntary contraction

Striated appearance

Voluntary control

Intercalated discs

#11

What happens when the calcium ions are removed from the cytoplasm of cardiac muscle cells?

Relaxation of the muscle

Contraction of the muscle

Initiation of muscle action potential

Depolarization of the cell membrane

#12

What is the role of the sarcoplasmic reticulum in cardiac muscle cells?

To synthesize proteins

To store and release calcium ions

To generate ATP

To regulate cell metabolism

#13

Which of the following is a characteristic of cardiac muscle compared to skeletal muscle?

T-tubules are larger and less abundant.

Presence of troponin-tropomyosin complex.

Presence of intercalated discs.

Striated appearance.