Question 1

Which of the following best describes the primary function of red blood cells (erythrocytes) in the circulatory system?

Accepted Answer

They transport oxygen and carbon dioxide between the lungs and tissues.

Question 2

Blood is considered a connective tissue because it:

Accepted Answer

Is composed of a fluid matrix (plasma) and formed elements.

Question 3

Which of the following is NOT a function of blood in the human body?

Accepted Answer

Producing energy for muscle contraction.

Question 4

Which blood component is responsible for fighting infections?

Accepted Answer

Leukocytes (white blood cells)

Question 5

A blood sample is centrifuged and separates into three layers. Which layer contains the majority of the formed elements?

Accepted Answer

Erythrocytes

Question 6

Which of the following statements about oxygenated and deoxygenated blood is correct?

Accepted Answer

Oxygenated blood appears brighter red due to higher O$_2$ content.

Question 7

Which of the following is the correct sequence for gas exchange in the human body, as shown in the diagram?

Accepted Answer

Ventilation → Diffusion at respiratory surface → Circulation → Diffusion at tissue

Question 8

Which type of blood cell is responsible for initiating blood clotting?

Accepted Answer

Platelets (thrombocytes)

Question 9

Plasma, the fluid matrix of blood, is primarily composed of:

Accepted Answer

Water and dissolved solutes

Question 10

Which of the following best explains why blood is able to transport both oxygen and carbon dioxide?

Accepted Answer

Red blood cells contain hemoglobin, which binds to O$_2$ and assists in CO$_2$ transport.

Question 11

A patient has a low count of leukocytes. Which of the following would they be most at risk for?

Accepted Answer

Increased susceptibility to infections

Question 12

Which of the following is a correct real-world application of blood’s transport function?

Accepted Answer

Insulin produced by the pancreas is delivered to muscle cells via the bloodstream.

Question 13

Which of the following blood cells is most directly involved in allergic reactions?

Accepted Answer

Basophils

Question 14

If a person’s blood sample shows a reduced plasma volume, which of the following symptoms might they experience?

Accepted Answer

Dehydration and reduced blood pressure

Question 15

Which of the following is a correct statement about the composition of blood?

Accepted Answer

Plasma is a straw-colored fluid that contains water, proteins, and dissolved solutes.

Question 16

Which of the following best describes the role of platelets in the circulatory system?

Accepted Answer

They initiate the process of blood clotting to prevent blood loss.

Question 17

Which of the following is a plausible consequence of a genetic disorder that prevents the production of plasma proteins?

Accepted Answer

Difficulty maintaining blood osmotic pressure and increased risk of edema.

Question 18

Which of the following is a correct match between blood cell type and its function?

Accepted Answer

Lymphocytes – immune response

Question 19

Which of the following would most likely occur if the plasma portion of blood was removed during a medical procedure?

Accepted Answer

Blood would lose its ability to transport dissolved nutrients and wastes.

Question 20

Which of the following is the most accurate description of the buffy coat in a centrifuged blood sample?

Accepted Answer

It consists of leukocytes and platelets.

Blood and Circulatory System: Structure, Function, and Gas Exchange

Study Guide - Practice Questions