A&P Exam 4 Review FA25

What is the largest diameter artery in the body?

• aorta
• capillary
• vein
• pulmonary artery

Smooth muscle cells that regulate blood flow from the thoroughfare channel into capillaries are called this:

• Precapillary sphincters
• Arteriovenous shunts
• Lymphatic valves
• Postcapillary sphincters

Blood going to the lungs through the pulmonary arteries contains a high concentration of ______ and a low concentration of ______.

• nitrogen, oxygen

• oxygen, carbon dioxide
• carbon monoxide, nitrogen
• carbon dioxide, oxygen

Venous return would be increased by this:

• Decreased heart rate

• Contraction of skeletal muscles

• Dilation of blood vessels

• Relaxation of skeletal muscles

Strong connective tissue strings that are attached to papillary muscles and to the cusps of the atrioventricular valves are called this:

• tendinous cords
• valvular ligaments
• atrial strings
• chordae tendineae

Given these valves:
1. aortic semilunar valve
2. bicuspid (mitral) valve
3. pulmonary semilunar valve
4. tricuspid valve
Arrange them in the order in which an erythrocyte would pass through them after returning to the heart from the left arm

• 3, 4, 1, 2
• 1, 2, 3, 4
• 4, 3, 2, 1
• 2, 4, 3, 1

Damage to cells of the AV bundle would prevent the cardiac impulse from reaching this:

• Atria
• Ventricles
• SA node

Given these structures of the conduction system of the heart:
1. atrioventricular bundle (Bundle of His)
2. AV node
3. bundle branches
4. Purkinje fibers
5. SA node
Choose the arrangement that lists the structures in the order an action potential passes through them.

• 5, 2, 1, 3, 4
• 5, 4, 3, 2, 1
• 2, 1, 3, 4, 5
• 1, 2, 3, 4, 5

In an EKG, the P wave represents this:

• Ventricular depolarization
• Atrial repolarization
• Ventricular repolarization
• Atrial depolarization

Cardiac output is defined as this:

• The amount of blood pumped by the heart per hour.
• The amount of blood pumped by the heart per minute.
• The amount of blood pumped by the heart per day.
• The amount of blood pumped by the heart per second.