$$F = CSA \times \text{fiber efficiency}$$

$$\text{Fatigue} \propto \text{Lactic Acid Accumulation}$$

$$\text{Contraction} \propto [Ca$$^{2+}$$]$$

Question 1

Which of the following best describes the structural features of a diarthrosis joint?

Accepted Answer

It contains a joint cavity filled with synovial fluid, articular cartilage, and is freely movable.

Question 2

A patient presents with inflammation of the bursae in the shoulder. Which term best describes this condition?

Accepted Answer

Bursitis

Question 3

Which movement term describes the action of decreasing the angle between two bones at a joint, such as bending the elbow?

Accepted Answer

Flexion

Question 4

Which of the following is NOT a function of the meniscus in a synovial joint?

Accepted Answer

Producing synovial fluid

Question 5

A muscle that opposes the action of the prime mover is called:

Accepted Answer

Antagonist

Question 6

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

Accepted Answer

Parallel

Question 7

A nurse needs to inject medication into the deltoid muscle. Which landmark is most important to avoid injury to underlying nerves?

Accepted Answer

Acromion process

Question 8

Which muscle type is characterized by involuntary control, striations, and branching fibers?

Accepted Answer

Cardiac muscle

Question 9

During muscle contraction, which structure shortens according to the sliding filament theory?

Accepted Answer

Sarcomere

Question 10

Which equation best represents the relationship between force, muscle cross-sectional area, and muscle fiber type?

Accepted Answer

$$F = CSA 	imes 	ext{fiber efficiency}$$

Question 11

Which of the following best describes the role of myoglobin in muscle cells?

Accepted Answer

Provides oxygen storage for aerobic metabolism

Question 12

A patient is unable to maintain muscle contraction over time, experiencing rapid fatigue. Which muscle fiber subtype is most likely deficient?

Accepted Answer

Type I (slow oxidative)

Question 13

Which of the following is TRUE regarding isotonic and isometric contractions?

Accepted Answer

Isotonic contractions involve muscle length change, while isometric contractions involve tension without length change.

Question 14

Which equation best describes the relationship between muscle fatigue and lactic acid accumulation?

Accepted Answer

$$	ext{Fatigue} \propto 	ext{Lactic Acid Accumulation}$$

Question 15

Which scenario best illustrates the action of a synergist muscle?

Accepted Answer

The brachialis assists the biceps brachii during elbow flexion.

Question 16

Which of the following best describes the neuromuscular junction?

Accepted Answer

A synapse between a motor neuron and a muscle fiber where acetylcholine is released.

Question 17

Which muscle disorder is characterized by progressive weakness due to autoimmune destruction of acetylcholine receptors?

Accepted Answer

Myasthenia gravis

Question 18

Which muscle arrangement is most efficient for generating force, as seen in the rectus femoris?

Accepted Answer

Pennate

Question 19

A patient with osteoarthritis has degeneration of articular cartilage in the knee. Which structure is most directly affected?

Accepted Answer

Articular cartilage

Question 20

Which equation best represents the relationship between muscle contraction and calcium ion concentration?

Accepted Answer

$$	ext{Contraction} \propto [Ca$$^{2+}$$]$$

Joints and Muscles: Structure, Function, and Disorders

Study Guide - Practice Questions