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

Question 1

Which of the following is NOT a function of the muscular system?

Accepted Answer

Production of red blood cells

Question 2

Which property of muscle tissue allows it to respond to chemical, mechanical, or local electrical signals?

Accepted Answer

Excitability

Question 3

A muscle cell's ability to stretch beyond its resting length without damage is called:

Accepted Answer

Extensibility

Question 4

Which muscle tissue type is responsible for voluntary movement and is characterized by multiple nuclei and striations?

Accepted Answer

Skeletal muscle

Question 5

Which of the following best describes the role of myofibrils in skeletal muscle fibers?

Accepted Answer

They are bundles of contractile and regulatory proteins responsible for muscle contraction.

Question 6

The sarcomere is defined as:

Accepted Answer

The region between two Z lines in a myofibril

Question 7

During muscle contraction, which phase involves the rapid increase in tension as crossbridge cycling occurs?

Accepted Answer

Contraction period

Question 8

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

Accepted Answer

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

Question 9

Which muscle is responsible for flexion of the forearm at the elbow joint?

Accepted Answer

Biceps brachii

Question 10

A patient is unable to rotate their head to the opposite side. Which muscle is most likely impaired?

Accepted Answer

Sternocleidomastoid

Question 11

Which of the following statements about slow-twitch muscle fibers is TRUE?

Accepted Answer

They have high myoglobin content and are adapted for endurance activities.

Question 12

Which muscle shape is best suited for generating the greatest force?

Accepted Answer

Multipennate

Question 13

Which of the following is the correct origin, insertion, and action for the Triceps brachii muscle?

Accepted Answer

Origin: scapula and humerus; Insertion: olecranon of ulna; Action: extension of forearm

Question 14

Which muscle is primarily responsible for closing the jaw during mastication?

Accepted Answer

Masseter

Question 15

Which of the following best describes the action of the rectus abdominis muscle?

Accepted Answer

Flexion of the vertebral column

Question 16

Which muscle is involved in abduction of the arm at the shoulder joint?

Accepted Answer

Deltoid

Question 17

Which of the following statements about muscle contraction is correct?

Accepted Answer

Isotonic concentric contraction occurs when muscle force is greater than external load and the muscle shortens.

Question 18

Which muscle is responsible for plantar flexion of the foot?

Accepted Answer

Gastrocnemius

Question 19

Which of the following is a synergist muscle that helps maintain the accuracy of motion and add force?

Accepted Answer

Synergist

Question 20

A muscle that only shortens the distance between its origin(s) and insertion(s) is demonstrating which principle?

Accepted Answer

Muscles only contract

Muscular System: Structure, Function, and Major Muscles

Study Guide - Practice Questions