Question 1

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

Accepted Answer

Compact bone is dense and organized into osteons, while spongy bone consists of a network of trabeculae.

Question 2

During endochondral ossification, which structure is replaced by bone tissue?

Accepted Answer

Cartilage model

Question 3

A patient presents with low blood calcium levels. Which hormone is most likely to be secreted in response, and what is its primary effect on bone?

Accepted Answer

Parathyroid hormone (PTH); stimulates osteoclasts to resorb bone

Question 4

Which artery supplies blood to the diaphysis of a long bone?

Accepted Answer

Nutrient artery

Question 5

If a patient has a fracture at the epiphyseal plate, which potential complication should be considered?

Accepted Answer

Impaired bone length growth due to damage to the growth plate

Question 6

Which bone cell is primarily responsible for bone resorption during remodeling?

Accepted Answer

Osteoclast

Question 7

A patient with osteoporosis is prescribed weight-bearing exercise. What is the physiological basis for this recommendation?

Accepted Answer

Weight-bearing exercise stimulates osteoblasts, promoting bone formation.

Question 8

Which of the following equations correctly represents the relationship between calcium ion concentration and parathyroid hormone secretion?

Accepted Answer

$$PTH \propto \frac{1}{[Ca$$^{2+}$$]}$$

Question 9

Which of the following is the correct sequence of events in the healing of a bone fracture?

Accepted Answer

Hematoma formation, fibrocartilaginous callus formation, bony callus formation, bone remodeling

Question 10

A patient with chronic kidney disease is found to have decreased calcium reabsorption. Which physiological response is most likely to occur?

Accepted Answer

Increased bone resorption to maintain blood calcium levels

Question 11

Which of the following best explains why bones are a major reservoir for calcium in the body?

Accepted Answer

Bones contain 99% of the body's calcium, which can be released or stored as needed for homeostasis.

Question 12

Which process is most directly responsible for the formation of flat bones such as those of the skull?

Accepted Answer

Intramembranous ossification

Question 13

A patient with a stress fracture in the tibia is advised to rest and avoid repetitive impact. What is the primary reason for this recommendation?

Accepted Answer

Rest prevents further microdamage and allows bone remodeling to repair the fracture.

Question 14

Which of the following is a correct statement about the role of osteocytes in bone physiology?

Accepted Answer

Osteocytes act as mechanosensors and help regulate bone remodeling.

Question 15

A patient with a fracture is found to have delayed healing. Which factor is most likely to contribute to this delay?

Accepted Answer

Poor blood supply to the fracture site

Question 16

Which of the following best describes the effect of calcitonin on bone?

Accepted Answer

Calcitonin inhibits osteoclast activity, promoting bone formation.

Question 17

Which of the following is the correct formula for the percentage of inorganic components in bone, given that bone is 67% inorganic?

Accepted Answer

$$	ext{Inorganic\%} = \frac{67}{100} 	imes 100$$

Question 18

A patient with a Potts fracture has a break in which part of the bone?

Accepted Answer

Distal fibula

Question 19

Which of the following best explains the role of the periosteal arteries in bone physiology?

Accepted Answer

They supply blood to the outer compact bone and periosteum.

Question 20

A patient with a deficiency in vitamin D is likely to experience which effect on bone physiology?

Accepted Answer

Decreased intestinal absorption of calcium, leading to weakened bones

Bone Physiology: Structure, Function, and Homeostasis

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