$$ \text{Mechanical Advantage} = \frac{\text{Effort Arm}}{\text{Load Arm}} $$

Question 1

Which of the following best describes the role of a synergist muscle during movement?

Accepted Answer

It adds extra force to the same movement and reduces undesirable or unnecessary movement.

Question 2

A muscle that crosses on the anterior side of a joint typically produces which movement?

Accepted Answer

Flexion

Question 3

Which fascicle arrangement is most likely to produce the greatest power, and why?

Accepted Answer

Multipennate, because it contains the most muscle fibers and shortens little.

Question 4

In a lever system, what is the mechanical advantage formula?

Accepted Answer

$$ 	ext{Mechanical Advantage} = \frac{	ext{Effort Arm}}{	ext{Load Arm}} $$

Question 5

Which muscle name indicates both its action and its location of attachment?

Accepted Answer

Sternocleidomastoid

Question 6

A patient is unable to abduct their arm at the shoulder. Which muscle is most likely impaired?

Accepted Answer

Deltoid

Question 7

If a muscle crosses the medial side of a joint, what movement does it produce?

Accepted Answer

Adduction

Question 8

Which lever class is most common in the human body and is exemplified by the action of the biceps brachii?

Accepted Answer

Third-class lever

Question 9

A muscle named 'extensor carpi radialis longus' tells you all of the following EXCEPT:

Accepted Answer

It is the shortest muscle in the group.

Question 10

Which of the following statements about muscle origin and insertion is correct?

Accepted Answer

The origin is the attachment point that moves the least.

Question 11

A muscle with fibers running straight along the axis of the body is most likely named:

Accepted Answer

Rectus

Question 12

Which lever system allows a small effort to move a large load, and what is the key anatomical feature?

Accepted Answer

Power lever; load is close to fulcrum and effort is far from fulcrum

Question 13

Which fascicle arrangement is found in muscles like the orbicularis oris and is responsible for closing openings?

Accepted Answer

Circular

Question 14

A muscle with three origins would most likely be named:

Accepted Answer

Triceps

Question 15

Which of the following is true regarding the relationship between muscle fiber length and power?

Accepted Answer

Power depends on the number of muscle fibers, not their length.

Question 16

During a calf raise, which lever class is being used and what is the anatomical arrangement?

Accepted Answer

Second-class lever; load is between fulcrum and effort

Question 17

If a muscle acts as a prime mover in one movement, what other roles might it play in different movements?

Accepted Answer

It can act as an antagonist or a synergist.

Question 18

Which muscle group is responsible for undoing the action performed by the prime mover?

Accepted Answer

Antagonist

Question 19

A muscle named 'rectus femoris' tells you that:

Accepted Answer

It is located in the thigh and fibers run straight.

Question 20

Which of the following best describes a fixator muscle?

Accepted Answer

It immobilizes the bone or muscle’s origin, providing a stable base for the prime mover.

The Muscular System: Structure, Function, and Mechanics

Study Guide - Practice Questions