Q: Which of the following equations correctly represents the breakdown of ATP during muscle contraction?

$$\mathrm{ATP} \rightarrow \mathrm{ADP} + \mathrm{P_i} + \text{energy}$$

Question 1

Which of the following correctly lists the three connective tissue layers of skeletal muscle from innermost to outermost?

Accepted Answer

Endomysium, perimysium, epimysium

Question 2

A patient presents with muscle weakness due to the destruction of acetylcholine receptors at the neuromuscular junction. Which condition best explains this scenario?

Accepted Answer

Myasthenia gravis

Question 3

During muscle contraction, which event occurs immediately after calcium ions bind to troponin?

Accepted Answer

Tropomyosin shifts to expose active sites on actin

Question 4

Which of the following best describes the function of creatine phosphate (CP) in skeletal muscle metabolism?

Accepted Answer

It provides a rapid source of ATP by donating a phosphate to ADP

Question 5

A muscle fiber is observed under a microscope. The region where thick and thin filaments overlap appears darker. What is this region called?

Accepted Answer

Zone of overlap

Question 6

Which of the following equations correctly represents the breakdown of ATP during muscle contraction?

Accepted Answer

$$\mathrm{ATP} ightarrow \mathrm{ADP} + \mathrm{P_i} + 	ext{energy}$$

Question 7

Which muscle is responsible for compressing the cheeks, as in blowing or sucking?

Accepted Answer

Buccinator

Question 8

A person is unable to elevate their shoulders. Which muscle is most likely impaired?

Accepted Answer

Trapezius

Question 9

Which of the following statements about smooth muscle is correct?

Accepted Answer

It contains calmodulin, which binds calcium

Question 10

During the sliding filament mechanism, what happens to the H zone as the sarcomere contracts?

Accepted Answer

It disappears

Question 11

Which of the following best describes isotonic muscle contraction?

Accepted Answer

The muscle shortens or lengthens while tension remains constant

Question 12

A patient is unable to flex their forearm at the elbow. Which muscle is most likely affected?

Accepted Answer

Biceps brachii

Question 13

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

Accepted Answer

Action potential → calcium release → troponin binds calcium → tropomyosin shifts → cross-bridge formation

Question 14

Which of the following best explains why rigor mortis occurs after death?

Accepted Answer

Lack of ATP prevents detachment of myosin heads from actin

Question 15

Which muscle is primarily responsible for inspiration by contracting and expanding the thoracic cavity?

Accepted Answer

Diaphragm

Question 16

Which of the following is a function of the sarcoplasmic reticulum in skeletal muscle fibers?

Accepted Answer

Storing and releasing calcium ions

Question 17

A muscle is described as having fascicles arranged in concentric rings. Which type of muscle arrangement is this?

Accepted Answer

Circular

Question 18

Which of the following best describes the role of ATP in muscle relaxation?

Accepted Answer

ATP is required to detach myosin heads from actin

Question 19

Which of the following muscles is responsible for flexion of the forearm at the elbow and is also a major supinator of the forearm?

Accepted Answer

Biceps brachii

Question 20

Which of the following statements about cardiac muscle is correct?

Accepted Answer

It contains intercalated discs with gap junctions and desmosomes

Skeletal Muscle Structure, Function, and Physiology: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard