Question 1

Which of the following best describes endochondral ossification?

Accepted Answer

Bone forms by replacing hyaline cartilage, forming most of the skeleton below the base of the skull except the clavicles.

Question 2

During the growth in length of a long bone, which zone of the epiphyseal plate is responsible for rapid cell division and pushing the epiphysis away from the diaphysis?

Accepted Answer

Proliferation (growth) zone

Question 3

A 12-year-old patient presents with bowed legs and enlarged bone ends. Laboratory tests reveal low serum calcium and vitamin D. What is the most likely diagnosis?

Accepted Answer

Rickets

Question 4

Which hormone is primarily responsible for stimulating osteoclast activity to increase blood calcium levels?

Accepted Answer

Parathyroid hormone (PTH)

Question 5

According to Wolf’s law, which of the following statements is correct?

Accepted Answer

Bones grow or remodel in response to the mechanical stresses placed on them.

Question 6

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 7

Which of the following best explains why weight-bearing exercise is recommended for osteoporosis prevention?

Accepted Answer

It stimulates bone remodeling, increasing bone mass and density.

Question 8

A patient has a fracture where the bone is crushed, as seen in vertebrae after a fall. What type of fracture is this?

Accepted Answer

Compression fracture

Question 9

Which of the following is a key difference between intramembranous and endochondral ossification?

Accepted Answer

Intramembranous ossification forms bone from fibrous membranes, while endochondral ossification replaces hyaline cartilage.

Question 10

Which of the following best describes the role of osteoclasts in bone remodeling?

Accepted Answer

They secrete lysosomal enzymes and protons to digest bone matrix, releasing calcium into the blood.

Question 11

A 70-year-old woman presents with a hip fracture after a minor fall. Her bone density is low, but the bone matrix is normal. What is the most likely diagnosis?

Accepted Answer

Osteoporosis

Question 12

Which of the following is NOT a risk factor for osteoporosis?

Accepted Answer

High levels of physical activity

Question 13

Which of the following drugs is used to decrease osteoclast activity and partially reverse osteoporosis in the spine?

Accepted Answer

Bisphosphonates

Question 14

Which of the following statements about bone remodeling is correct?

Accepted Answer

Bone remodeling involves both bone deposit by osteoblasts and bone resorption by osteoclasts.

Question 15

A patient with Paget’s disease is likely to have which of the following bone characteristics?

Accepted Answer

Excessive and haphazard bone deposit and resorption, with a high ratio of spongy to compact bone

Question 16

Which of the following best describes the effect of leptin on bone density?

Accepted Answer

Leptin inhibits osteoblast activity, potentially reducing bone density.

Question 17

Which of the following is a correct statement about the epiphyseal plate during bone growth?

Accepted Answer

The rate of cartilage growth is balanced by bone replacement, maintaining constant thickness.

Question 18

Which of the following is a possible consequence of sustained high blood calcium levels?

Accepted Answer

Nonresponsiveness of neuromuscular tissue and formation of kidney stones

Question 19

Which of the following best explains why bones of bedridden patients become featureless?

Accepted Answer

Lack of mechanical stress leads to reduced bone remodeling and loss of bone features.

Question 20

Which of the following is true regarding the role of alkaline phosphatase in bone deposit?

Accepted Answer

It is required for the mineralization of bone matrix by increasing the concentration of calcium and phosphate ions.

Bones and Skeletal Tissues: Development, Growth, Remodeling, Repair, and Disorders

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