Question 1

Which connective tissue layer directly surrounds individual muscle fibers and plays a crucial role in isolating each cell electrically?

Accepted Answer

Endomysium

Question 2

A patient is exposed to a nerve gas that inhibits acetylcholinesterase (AChE) at the neuromuscular junction. What is the most likely effect on their muscle contraction?

Accepted Answer

Muscle contraction will be prolonged and may lead to spastic paralysis.

Question 3

Where are acetylcholine (ACh) receptors located in the neuromuscular junction?

Accepted Answer

On the sarcolemma at the motor end plate

Question 4

If a drug binds to the ACh receptor and blocks it, what will happen to muscle contraction?

Accepted Answer

Muscle contraction will not occur.

Question 5

After the motor end plate depolarizes, which event occurs next in the process of muscle contraction?

Accepted Answer

Calcium is released from the sarcoplasmic reticulum.

Question 6

During muscle contraction, where is the concentration of calcium ions highest?

Accepted Answer

In the sarcoplasm

Question 7

Which of the following best describes the role of ATP in the cross-bridge cycle?

Accepted Answer

ATP hydrolysis provides energy for myosin head movement and detachment from actin.

Question 8

Which muscle fiber type is most likely to be recruited during a marathon?

Accepted Answer

Red/slow fibers

Question 9

What is the primary drawback of glycolysis as a method of ATP production during intense exercise?

Accepted Answer

It produces lactic acid, leading to muscle fatigue.

Question 10

Which structure is responsible for binding calcium within the terminal cisternae of the sarcoplasmic reticulum?

Accepted Answer

Calsequestrin

Question 11

A muscle twitch is defined as:

Accepted Answer

A single, brief contraction and relaxation cycle in a muscle fiber.

Question 12

If the frequency of stimulation increases, which phenomenon can occur, as shown in a graph of muscle tension vs. frequency?

Accepted Answer

Muscle tension increases, leading to tetanus.

Question 13

Which of the following is true regarding the anatomy of a sarcomere during contraction compared to rest?

Accepted Answer

The I band and H zone decrease in width during contraction.

Question 14

Which lever system is exemplified by the action of the triceps brachii extending the forearm at the elbow?

Accepted Answer

First-class lever

Question 15

Which muscle fascicle arrangement allows for the greatest range of motion but the least force production?

Accepted Answer

Parallel

Question 16

Which of the following statements best describes the relationship between agonist and antagonist muscles?

Accepted Answer

Agonists produce a specific movement, while antagonists oppose that movement.

Question 17

Which of the following is a unique feature of cardiac muscle that distinguishes it from skeletal and smooth muscle?

Accepted Answer

Presence of intercalated discs

Question 18

During peak levels of activity, most ATP in skeletal muscle is produced by:

Accepted Answer

Glycolysis

Question 19

Which equation best represents the breakdown of creatine phosphate (CP) to produce ATP in muscle cells?

Accepted Answer

$$	ext{CP} + 	ext{ADP} ightarrow 	ext{Creatine} + 	ext{ATP}$$

Question 20

A patient with a genetic disorder affecting troponin function would most likely experience which of the following?

Accepted Answer

Impaired regulation of muscle contraction due to inability to bind calcium

Anatomy & Physiology Exam 3 Study Guidance: Muscular System and Muscle Physiology

Guida di studio - Domande di pratica

Study guide - Flashcard