NPA Anatomy & Physiology of the Circulatory System 2 — Questions and Answers
Question 1: Which vein runs along the lateral (thumb) side of the forearm and is considered the third choice for venipuncture in the antecubital fossa?
- Basilic vein
- Median cubital vein
- Cephalic vein (Correct answer)
- Median antebrachial vein
Correct answer: Cephalic vein
The cephalic vein runs along the lateral (radial/thumb) side of the forearm and is generally the third choice for venipuncture due to its tendency to roll.
Question 2: Approximately how much blood does the average adult human body contain?
- 2–3 liters
- 4–6 liters (Correct answer)
- 7–9 liters
- 10–12 liters
Correct answer: 4–6 liters
The average adult body contains approximately 4–6 liters of blood, representing about 7–8% of total body weight.
Question 3: What is the primary role of erythrocytes (red blood cells)?
- Fight infection and produce antibodies
- Transport oxygen and carbon dioxide (Correct answer)
- Facilitate blood clotting at injury sites
- Produce clotting factors in the liver
Correct answer: Transport oxygen and carbon dioxide
Erythrocytes contain hemoglobin, which binds oxygen for transport to tissues and carries carbon dioxide back to the lungs.
Question 4: Which vein runs along the medial (pinky finger) side of the forearm and is considered the second choice for antecubital venipuncture?
- Cephalic vein
- Median antebrachial vein
- Basilic vein (Correct answer)
- Median cubital vein
Correct answer: Basilic vein
The basilic vein runs along the medial (ulnar) side of the forearm and is the second choice, though it is close to the brachial artery and median nerve.
Question 5: What is plasma?
- The liquid portion of blood after clotting factors have been removed
- The cellular portion of whole blood
- The liquid portion of blood containing clotting factors and proteins (Correct answer)
- Concentrated red blood cells separated by centrifugation
Correct answer: The liquid portion of blood containing clotting factors and proteins
Plasma is the liquid portion of whole blood that contains water, proteins (including clotting factors), hormones, and electrolytes.
Question 6: Which pulmonary vessel is unique in that it carries deoxygenated blood?
- Pulmonary veins
- Pulmonary arteries (Correct answer)
- Aorta
- Superior vena cava
Correct answer: Pulmonary arteries
The pulmonary arteries carry deoxygenated blood from the right ventricle to the lungs — the only arteries in the body that carry deoxygenated blood.
Question 7: The sinoatrial (SA) node is often called the 'pacemaker of the heart' because it:
- Controls blood pressure in the aorta
- Initiates the electrical impulse that triggers each heartbeat (Correct answer)
- Regulates oxygen levels in coronary arteries
- Prevents backflow between heart chambers
Correct answer: Initiates the electrical impulse that triggers each heartbeat
The SA node generates spontaneous electrical impulses that spread through the heart, triggering coordinated muscle contractions and setting the heart rate.
NPA Anatomy & Physiology of the Circulatory System 2
Which vein runs along the lateral (thumb) side of the forearm and is considered the third choice for venipuncture in the antecubital fossa?