$$MA = \frac{\text{Effort Arm}}{\text{Load Arm}}$$

Question 1

Which of the following best describes the main difference between the origin and insertion of a skeletal muscle?

Accepted Answer

Origin is the attachment point that does not move during contraction, while insertion is the attachment point that moves.

Question 2

A patient presents with difficulty in plantar flexion of the ankle. Which muscle is most likely affected?

Accepted Answer

Gastrocnemius

Question 3

Which of the following is TRUE regarding smooth muscle tissue?

Accepted Answer

Smooth muscle cells are electrically coupled by gap junctions, allowing slow, synchronized contractions.

Question 4

During resistance exercise, which physiological change is most responsible for increased muscle strength?

Accepted Answer

Muscle hypertrophy due to increase in fiber size

Question 5

Which muscle is the prime mover for jaw closure during mastication?

Accepted Answer

Temporalis

Question 6

A neurotransmitter causes contraction in the smooth muscle of the intestine but relaxation in the smooth muscle of the airway. This is an example of:

Accepted Answer

Neural regulation with organ-specific effects

Question 7

Which of the following factors does NOT directly increase the force of muscle contraction?

Accepted Answer

Decrease in muscle stretch below 80% resting length

Question 8

Which muscle group is primarily responsible for flexion of the thigh at the hip?

Accepted Answer

Iliopsoas (iliacus and psoas major)

Question 9

What is the function of the pelvic diaphragm?

Accepted Answer

Seals the inferior outlet of the pelvis and supports pelvic organs

Question 10

Which of the following correctly matches a muscle with its action?

Accepted Answer

Rectus abdominis – flexes and rotates trunk

Question 11

A muscle that acts as a synergist during elbow flexion is:

Accepted Answer

Brachialis

Question 12

Which pattern of fascicle arrangement allows for the greatest range of motion but less power?

Accepted Answer

Parallel

Question 13

Which of the following is a function of the external intercostal muscles?

Accepted Answer

Enlarge the rib cage during inspiration

Question 14

Which muscle is NOT part of the rotator cuff?

Accepted Answer

Deltoid

Question 15

Which equation best represents the mechanical advantage of a lever system in the body?

Accepted Answer

$$MA = \frac{	ext{Effort Arm}}{	ext{Load Arm}}$$

Question 16

Which muscle is responsible for abduction and lateral rotation of the thigh?

Accepted Answer

Gluteus maximus

Question 17

Which of the following statements about muscle contraction velocity is correct?

Accepted Answer

The greater the load, the slower the duration of contraction.

Question 18

Which muscle group is most likely to be injured in a 'pulled groin'?

Accepted Answer

Adductor group (adductor magnus, adductor longus, adductor brevis, pectineus, gracilis)

Question 19

Which muscle is the prime mover for extension of the forearm at the elbow?

Accepted Answer

Triceps brachii

Question 20

Which of the following is a characteristic of varicosities in smooth muscle tissue?

Accepted Answer

They store and release neurotransmitters into a wide synaptic cleft called a diffuse junction.

Chapter 10: The Muscular System – Structure, Function, and Major Muscles

Study Guide - Practice Questions