Q: Which of the following equations correctly represents the mechanical advantage of a lever in the musculoskeletal system?

$$Load \times d_1$ = Effort \times d_2$

Question 1

Which of the following best describes the function of osteoclasts in bone tissue?

Accepted Answer

They break down bone matrix, releasing calcium and phosphate into the blood.

Question 2

A patient presents with bones that are soft and easily deformed. Laboratory tests reveal a deficiency in vitamin D. Which condition is most likely present, and what is the underlying cause?

Accepted Answer

Osteomalacia; inadequate mineralization of bone matrix due to vitamin D deficiency

Question 3

Which of the following equations correctly represents the mechanical advantage of a lever in the musculoskeletal system?

Accepted Answer

$$Load 	imes d_1$ = Effort 	imes d_2$

Question 4

During muscle contraction, which event occurs immediately after Ca$$^{2+}$$ binds to troponin?

Accepted Answer

Tropomyosin shifts to expose active sites on actin.

Question 5

A 65-year-old woman is diagnosed with osteoporosis. Which of the following interventions is LEAST likely to increase her bone mineral density?

Accepted Answer

Low-intensity, non-weight-bearing exercise

Question 6

Which of the following best explains why ATP is required for muscle relaxation after contraction?

Accepted Answer

ATP is needed to pump Ca$$^{2+}$$ back into the sarcoplasmic reticulum, ending contraction.

Question 7

A patient with a genetic defect in collagen synthesis is most likely to have which of the following bone disorders?

Accepted Answer

Osteogenesis imperfecta

Question 8

Which of the following statements about the sarcoplasmic reticulum (SR) in skeletal muscle is correct?

Accepted Answer

The SR stores and releases Ca$$^{2+} to $$regulate muscle contraction.

Question 9

Which of the following best describes the role of parathyroid hormone (PTH) in calcium homeostasis?

Accepted Answer

PTH stimulates osteoclasts to degrade bone matrix and release Ca$$^{2+}$$ into the blood.

Question 10

A muscle fiber is stimulated at a frequency that does not allow complete relaxation between stimuli, resulting in a sustained, quivering contraction. What is this phenomenon called?

Accepted Answer

Unfused (incomplete) tetanus

Question 11

Which of the following is a function of the integumentary system?

Accepted Answer

Protection against mechanical and chemical injury

Question 12

Which of the following best describes the process of bone remodeling?

Accepted Answer

Osteoblasts and osteoclasts work together to renew bone tissue in response to mechanical stress and hormonal signals.

Question 13

A 30-year-old male suffers a fracture in the midshaft of his femur. According to Wolff's law, what is most likely to occur during the healing process?

Accepted Answer

Bone will remodel in response to the mechanical stresses placed upon it.

Question 14

Which of the following best explains why fast glycolytic muscle fibers fatigue more quickly than slow oxidative fibers?

Accepted Answer

They use anaerobic glycolysis, which produces lactic acid and less ATP.

Question 15

Which of the following is the correct sequence of events for excitation-contraction coupling in skeletal muscle?

Accepted Answer

Action potential travels along sarcolemma → Ca$$^{2+}$$ released from SR → Ca$$^{2+}$$ binds to troponin → Tropomyosin shifts → Cross-bridge formation

Question 16

A patient is unable to produce enough acetylcholine at the neuromuscular junction. Which of the following symptoms would most likely be observed?

Accepted Answer

Muscle weakness and fatigue

Question 17

Which of the following best describes the function of the stratum corneum in the epidermis?

Accepted Answer

It provides a waterproof barrier and protection from abrasion.

Question 18

Which of the following is a correct statement about the role of ATP in muscle contraction?

Accepted Answer

ATP hydrolysis powers the movement of myosin heads during the cross-bridge cycle.

Question 19

A 45-year-old man experiences muscle fatigue during intense exercise. Which of the following is the primary cause of this fatigue?

Accepted Answer

Accumulation of lactic acid and depletion of ATP

Comprehensive Study Notes: Tissue Types, Integumentary System, Skeletal System, and Muscular System

Guida di studio - Domande di pratica

Study guide - Flashcard