Q: Which equation best represents the negative feedback loop for calcitonin in response to increased blood calcium levels?

$$\text{Increased blood } [Ca$$^{2+}$$] \rightarrow \text{Increased calcitonin} \rightarrow \text{Decreased osteoclast activity} \rightarrow \text{Decreased blood } [Ca$$^{2+}$$]$$

Q: Which equation best describes the relationship between bone resorption and deposition in osteoporosis?

$$\text{Bone resorption rate} \u003e \text{Bone deposition rate}$$

Question 1

Which process is responsible for the formation of most bones below the skull, such as the femur and humerus, during embryonic development?

Accepted Answer

Endochondral ossification

Question 2

During intramembranous ossification, which type of cell initially forms the fibrous connective tissue membrane?

Accepted Answer

Mesenchymal cells

Question 3

Which hormone stimulates osteoblast activity and leads to faster closure of the epiphyseal plate during puberty?

Accepted Answer

Estrogen

Question 4

A patient presents with bowed legs and deformities of the rib cage. Laboratory tests reveal low serum calcium and vitamin D levels. What is the most likely diagnosis?

Accepted Answer

Rickets

Question 5

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

Accepted Answer

They break down bone matrix by secreting lysosomal enzymes and acids.

Question 6

Which type of fracture is characterized by bone fragments into three or more pieces and is most common in the elderly?

Accepted Answer

Comminuted fracture

Question 7

A child with hypersecretion of growth hormone from the pituitary gland is most likely to develop which condition?

Accepted Answer

Gigantism

Question 8

Which equation best represents the negative feedback loop for calcitonin in response to increased blood calcium levels?

Accepted Answer

$$	ext{Increased blood } [Ca$$^{2+}$$] ightarrow 	ext{Increased calcitonin} ightarrow 	ext{Decreased osteoclast activity} ightarrow 	ext{Decreased blood } [Ca$$^{2+}$$]$$

Question 9

Which nutritional factor is essential for the mineralization of bone and is required for alkaline phosphatase activity?

Accepted Answer

Vitamin D

Question 10

During bone healing after a fracture, which step immediately follows the formation of a hematoma?

Accepted Answer

Granulation tissue formation

Question 11

Which of the following is true regarding Paget's disease?

Accepted Answer

It involves excessive bone formation and breakdown, often localized in the spine, pelvis, femur, and skull.

Question 12

Which zone in long bone growth is responsible for the actual formation of new bone tissue?

Accepted Answer

Osteogenic zone

Question 13

Which hormone antagonistically regulates blood calcium levels with calcitonin?

Accepted Answer

Parathyroid hormone

Question 14

A 65-year-old woman presents with frequent bone fractures and a decrease in bone mass. Which condition is most likely responsible?

Accepted Answer

Osteoporosis

Question 15

Which of the following best describes appositional growth in bone?

Accepted Answer

Increase in bone thickness by osteoblasts secreting matrix on the external surface

Question 16

Which type of fracture is most commonly seen in children and involves one side of the bone breaking while the other side bends?

Accepted Answer

Greenstick fracture

Question 17

Which of the following is a direct effect of insulin on bone tissue?

Accepted Answer

Stimulates bone formation

Question 18

Which equation best describes the relationship between bone resorption and deposition in osteoporosis?

Accepted Answer

$$	ext{Bone resorption rate} \u003e 	ext{Bone deposition rate}$$

Question 19

Which of the following is NOT a typical site for Paget's disease?

Accepted Answer

Radius

Question 20

Which of the following is a common cause of osteomalacia in adults?

Accepted Answer

Insufficient calcium or vitamin D in the diet

Bone Development, Growth, and Homeostasis: Chapter 6 Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard