Q: Which of the following is the correct sequence of events in the formation of a blood clot?

$$\text{Prothrombin} \rightarrow \text{Thrombin} \rightarrow \text{Fibrinogen} \rightarrow \text{Fibrin}$$

Question 1

Which of the following best describes the structural unit of compact bone and its main components?

Accepted Answer

The osteon, consisting of concentric lamellae surrounding a central canal containing blood vessels and nerves.

Question 2

During bone remodeling, which hormone increases blood calcium levels by stimulating osteoclast activity?

Accepted Answer

Parathyroid hormone (PTH)

Question 3

A patient is diagnosed with osteoporosis, a condition characterized by decreased bone density. Which of the following best explains why post-menopausal women are at higher risk?

Accepted Answer

Decreased estrogen levels reduce inhibition of osteoclasts, increasing bone resorption.

Question 4

Which of the following correctly matches the type of joint with its example?

Accepted Answer

Synovial joint – knee

Question 5

Which of the following best describes the role of calcium ions ($$\mathrm{Ca$$^{2+}$$}) in $$skeletal muscle contraction?

Accepted Answer

They bind to troponin, causing tropomyosin to move and expose binding sites on actin.

Question 6

A person is unable to extend their forearm at the elbow after an injury. Which muscle is most likely damaged?

Accepted Answer

Triceps brachii

Question 7

Which of the following best describes the difference between red and white blood cells?

Accepted Answer

Red blood cells lack a nucleus and transport oxygen; white blood cells have a nucleus and are involved in immune defense.

Question 8

A patient with type O negative blood requires a transfusion. Which blood type(s) can safely be donated to this patient?

Accepted Answer

O negative only

Question 9

Which of the following is the correct sequence of events in the formation of a blood clot?

Accepted Answer

$$	ext{Prothrombin} ightarrow 	ext{Thrombin} ightarrow 	ext{Fibrinogen} ightarrow 	ext{Fibrin}$$

Question 10

Which vessel carries oxygen-rich blood from the lungs to the heart?

Accepted Answer

Pulmonary vein

Question 11

A patient has a blood pressure reading of $$140/90$$ mmHg. What does the number $$140$$ represent?

Accepted Answer

Systolic pressure, the pressure during ventricular contraction

Question 12

Which of the following best describes the function of the lymphatic system?

Accepted Answer

It returns excess interstitial fluid to the bloodstream and provides immune defense.

Question 13

Which of the following is a correct statement about the cardiac conduction system?

Accepted Answer

The sinoatrial (SA) node initiates the heartbeat and sets the pace for the heart.

Question 14

Which of the following best describes the difference between active and passive immunity?

Accepted Answer

Active immunity involves the production of antibodies by the body; passive immunity involves receiving antibodies from another source.

Question 15

A child receives a vaccine and later is exposed to the same pathogen. Which immune response will be stronger and faster, and why?

Accepted Answer

The secondary response, due to the presence of memory cells generated by the vaccine.

Question 16

Which of the following best describes the role of cytotoxic T cells in the immune system?

Accepted Answer

They destroy infected or cancerous cells by releasing perforin and granzymes.

Question 17

A person with an autoimmune disease is experiencing tissue damage. Which of the following best explains this phenomenon?

Accepted Answer

The immune system is attacking the body's own cells as if they were foreign.

Question 18

Which of the following best describes the process of inflammation?

Accepted Answer

It is a nonspecific response characterized by redness, heat, swelling, and pain, caused by the release of histamine.

Question 19

Which of the following best explains why RhoGAM is administered to Rh-negative mothers during pregnancy?

Accepted Answer

To prevent the mother's immune system from producing anti-Rh antibodies that could attack fetal red blood cells.

Question 20

Which of the following best describes the function of the pericardium?

Accepted Answer

It is a protective sac that surrounds the heart and reduces friction during heartbeats.

Human Biology Study Guide: Skeleton, Muscles, Blood, Cardiovascular, and Immune Systems

Study Guide - Practice Questions

Study Guide - Flashcards