Question 1

Which of the following best explains why newborns have more bones than adults?

Accepted Answer

Newborns have more bones because their skeletons contain many cartilage models that fuse during growth.

Question 2

Which bone cell is primarily responsible for breaking down bone matrix and releasing calcium into the blood?

Accepted Answer

Osteoclast

Question 3

A patient presents with a fracture along the growth plate of their femur. Which type of fracture is this, and why is it clinically significant?

Accepted Answer

Epiphyseal fracture; it can disrupt bone growth by damaging the epiphyseal cartilage.

Question 4

Which of the following is the correct chemical formula for hydroxyapatite, the primary mineral component of bone matrix?

Accepted Answer

$$\mathrm{Ca_{10}(PO_4$)_6(OH)_2}$$

Question 5

During endochondral ossification, what is the primary function of the epiphyseal plate?

Accepted Answer

It allows for interstitial growth of bone, enabling lengthening during childhood and adolescence.

Question 6

Which hormone increases blood calcium levels by stimulating osteoclast activity, increasing intestinal absorption, and decreasing renal excretion?

Accepted Answer

Parathyroid hormone (PTH)

Question 7

A 65-year-old woman is diagnosed with osteoporosis. Which of the following best explains the pathophysiology of her condition?

Accepted Answer

Osteoclast activity exceeds osteoblast activity, resulting in decreased bone mass and increased fragility.

Question 8

Which vitamin is essential for collagen synthesis and osteoblast differentiation, and its deficiency can lead to weakened bones?

Accepted Answer

Vitamin C

Question 9

A long bone is fractured. Which sequence correctly describes the four steps of bone repair?

Accepted Answer

Bleeding and hematoma formation, callus formation, spongy bone formation, compact bone remodeling

Question 10

Which bone marking is most likely to serve as a passageway for blood vessels and nerves?

Accepted Answer

Depressions, grooves, tunnels, or openings

Question 11

Which of the following best describes the structure of a flat bone?

Accepted Answer

Two layers of compact bone with a layer of spongy bone (diploë) in between

Question 12

Which of the following is NOT a function of the periosteum?

Accepted Answer

Initiates endochondral ossification in the embryo

Question 13

A patient exposed to radioactive plutonium is at risk for long-term health issues because:

Accepted Answer

Osteoblasts can incorporate plutonium into the bone matrix, which is slowly released during bone remodeling.

Question 14

Which of the following best describes the difference between compact bone and spongy bone?

Accepted Answer

Compact bone is organized into osteons with concentric lamellae, while spongy bone consists of trabeculae without osteons.

Question 15

Which equation best represents the relationship between bone mass and exercise, assuming bone mass increases proportionally with osteoblast activity?

Accepted Answer

$$	ext{Bone Mass} = k 	imes 	ext{Osteoblast Activity}$$, where $$k is a $$proportionality constant

Question 16

Which of the following scenarios would most likely result in decreased blood calcium levels?

Accepted Answer

Increased secretion of calcitonin, which inhibits osteoclasts and increases renal excretion of calcium

Question 17

Which bone cell type is derived from mesenchymal stem cells and is essential for fracture repair?

Accepted Answer

Osteogenic cell

Question 18

Which of the following best explains why weight-bearing exercise is recommended for patients with osteopenia?

Accepted Answer

It increases osteoblast activity, promoting bone formation and increasing bone mass.

Question 19

Which of the following is a plausible consequence of a greenstick fracture in a child?

Accepted Answer

The bone bends on one side and fractures on the other, due to incomplete ossification.

Chapter 6: Bones and Skeletal Tissue – Study Notes

Study Guide - Practice Questions