CBET Anatomy and Physiology Basics 5

Question 1

During inspiration, the diaphragm contracts and moves inferiorly, causing intrathoracic pressure to:

Accepted Answer

Decrease, drawing air into the lungs

Answer

Increase, pushing air out of the lungs

Answer

Remain unchanged due to chest wall recoil

Answer

Equalize with atmospheric pressure immediately

Question 2

Which ion is primarily responsible for the depolarization phase of a cardiac action potential?

Accepted Answer

Sodium (Na⁺) influx

Answer

Potassium (K⁺) influx

Answer

Calcium (Ca²⁺) influx

Answer

Chloride (Cl⁻) influx

Question 3

A ventilator-dependent patient has a tidal volume of 500 mL and a respiratory rate of 12 breaths/min. What is the minute ventilation?

Accepted Answer

6,000 mL/min

Answer

500 mL/min

Answer

4,200 mL/min

Answer

7,200 mL/min

Question 4

The sinoatrial (SA) node is located in which chamber of the heart?

Accepted Answer

Right atrium

Answer

Left atrium

Answer

Right ventricle

Answer

Interventricular septum

Question 5

Which blood vessel carries oxygenated blood from the lungs back to the heart?

Accepted Answer

Pulmonary vein

Answer

Pulmonary artery

Answer

Aorta

Answer

Superior vena cava

Question 6

The myelin sheath surrounding nerve axons is produced by which cells in the peripheral nervous system?

Accepted Answer

Schwann cells

Answer

Astrocytes

Answer

Oligodendrocytes

Answer

Microglia

Question 7

In a patient connected to an ECG monitor, the PR interval represents the time for electrical conduction from the:

Accepted Answer

SA node to the AV node, through the His-Purkinje system to the ventricles

Answer

SA node through the atria to the ventricular myocardium

Answer

Bundle of His through the Purkinje fibers

Answer

AV node through the bundle branches to Purkinje fibers