Question 1

Which muscle is primarily responsible for closing the eyelids, such as during blinking or squinting?

Accepted Answer

Orbicularis occuli

Question 2

A patient presents with difficulty flexing their forearm at the elbow after an injury. Which muscle is most likely affected?

Accepted Answer

Brachioradialis

Question 3

During a sprint, which muscle is primarily responsible for extending the knee?

Accepted Answer

Rectus femoris

Question 4

Which muscle is involved in the movement of the jaw during chewing, specifically elevating the mandible?

Accepted Answer

Masseter

Question 5

A tennis player complains of pain on the lateral side of their forearm after repetitive wrist extension. Which muscle is most likely overused?

Accepted Answer

Extensor carpi radialis longus

Question 6

Which muscle is responsible for abduction of the arm at the shoulder joint?

Accepted Answer

Deltoid

Question 7

A runner experiences pain in the Achilles tendon. Which muscle's contraction most directly transmits force through this tendon?

Accepted Answer

Gastrocnemius

Question 8

Which muscle is primarily responsible for flexing the fingers, such as when making a fist?

Accepted Answer

Flexor digitorum longus

Question 9

A patient with a lesion affecting the sternocleidomastoid muscle would have difficulty performing which movement?

Accepted Answer

Rotating the head to the opposite side

Question 10

Which muscle group is most important for stabilizing the pelvis during walking?

Accepted Answer

Gluteus maximus, medius & minimus

Question 11

If a person is unable to dorsiflex their foot, which muscle is most likely impaired?

Accepted Answer

Tibialis anterior

Question 12

Which muscle is involved in compressing the abdominal contents, such as during forced expiration?

Accepted Answer

External oblique

Question 13

A weightlifter performing a biceps curl is primarily using which muscle to flex the elbow?

Accepted Answer

Biceps brachii

Question 14

Which muscle is responsible for the adduction of the thigh at the hip joint?

Accepted Answer

Adductor longus

Question 15

During a sit-up, which muscle is most active in flexing the vertebral column?

Accepted Answer

Rectus abdominus

Question 16

A patient with weakness in wrist flexion is most likely to have damage to which muscle?

Accepted Answer

Flexor carpi ulnaris

Question 17

Which muscle is primarily responsible for smiling by elevating the corners of the mouth?

Accepted Answer

Zygomaticus

Question 18

A patient is unable to abduct their thigh. Which muscle is most likely injured?

Accepted Answer

Tensor fascia latae

Question 19

Which muscle is most involved in the extension of the forearm at the elbow joint?

Accepted Answer

Triceps brachii

Question 20

A patient presents with difficulty elevating their scapula, such as when shrugging their shoulders. Which muscle is most likely affected?

Accepted Answer

Trapezius

Human Muscle Models: Key Muscles and Their Functions

Study Guide - Practice Questions