PAX Physiology

Question 1

The sinoatrial (SA) node is the heart's natural pacemaker. Where is it located?

Accepted Answer

Right atrium

Answer

Left ventricle

Answer

Left atrium

Answer

Right ventricle

Question 2

Which blood vessels carry oxygenated blood away from the heart in systemic circulation?

Accepted Answer

Arteries

Answer

Veins

Answer

Venules

Answer

Capillaries

Question 3

During inhalation, what happens to the diaphragm?

Accepted Answer

It contracts and moves downward

Answer

It relaxes and moves upward

Answer

It remains stationary

Answer

It moves laterally

Question 4

Which molecule in red blood cells binds to oxygen for transport throughout the body?

Accepted Answer

Hemoglobin

Answer

Myoglobin

Answer

Albumin

Answer

Fibrinogen

Question 5

What is the normal resting heart rate range for a healthy adult?

Accepted Answer

60–100 beats per minute

Answer

40–60 beats per minute

Answer

100–120 beats per minute

Answer

120–150 beats per minute

Question 6

Gas exchange in the lungs — oxygen entering the blood and carbon dioxide leaving — occurs in which structures?

Accepted Answer

Alveoli

Answer

Bronchi

Answer

Bronchioles

Answer

Trachea

Question 7

What term describes the total volume of blood pumped by the heart per minute?

Accepted Answer

Cardiac output

Answer

Stroke volume

Answer

Heart rate

Answer

Ejection fraction