Question 1

Which of the following best describes the histological characteristics of skeletal muscle fibers as seen under the microscope?

Accepted Answer

Long cylindrical cells, multiple peripheral nuclei, striations present

Question 2

Which structure in the sarcomere serves as the attachment site for thin filaments and marks the boundary between adjacent sarcomeres?

Accepted Answer

Z disc

Question 3

A patient presents with difficulty lifting the front of their foot while walking, resulting in their toes dragging. Which muscle is most likely affected?

Accepted Answer

Tibialis anterior

Question 4

Which muscle is primarily responsible for the action of smiling?

Accepted Answer

Zygomaticus

Question 5

During inspiration, which two muscles are primarily responsible for increasing the volume of the thoracic cavity?

Accepted Answer

External intercostals and diaphragm

Question 6

Which of the following is a function of intercalated discs in cardiac muscle?

Accepted Answer

Allow rapid transmission of electrical impulses between cells

Question 7

Which muscle group is most prone to injury in baseball pitchers due to repetitive overhead throwing motions?

Accepted Answer

Rotator cuff muscles

Question 8

If the triceps brachii is the agonist for forearm extension, which muscle acts as its antagonist during forearm flexion?

Accepted Answer

Biceps brachii

Question 9

Which abdominal muscle is the deepest, lying beneath all other abdominal muscles?

Accepted Answer

Transversus abdominis

Question 10

Which of the following best describes the action of the sternocleidomastoid muscle when turning the head to the right?

Accepted Answer

The left sternocleidomastoid contracts

Question 11

Which two muscles synergistically close the jaw during chewing?

Accepted Answer

Masseter and temporalis

Question 12

Which muscle is responsible for plantar flexion of the foot and attaches to the calcaneal tendon?

Accepted Answer

Gastrocnemius

Question 13

Which of the following is NOT a function of skeletal muscle?

Accepted Answer

Secretion of digestive enzymes

Question 14

Which structure in a skeletal muscle fiber stores calcium ions necessary for muscle contraction?

Accepted Answer

Sarcoplasmic reticulum

Question 15

Which muscle is primarily responsible for crossing the legs by flexing the thigh and medially rotating the leg?

Accepted Answer

Sartorius

Question 16

Which of the following best describes the arrangement of myofilaments in the A band of a sarcomere?

Accepted Answer

Both thick and thin filaments overlapping

Question 17

Which muscle is responsible for elevating the scapula?

Accepted Answer

Trapezius

Question 18

Which muscle group is responsible for extending the knee?

Accepted Answer

Quadriceps femoris

Question 19

Which muscle is the primary flexor of the forearm at the elbow joint?

Accepted Answer

Brachialis

Question 20

Which of the following best explains why intercalated discs are only found in cardiac muscle?

Accepted Answer

Cardiac muscle requires rapid, synchronized contraction for effective pumping

Study Guide: Muscular System (Chapter 9)

Study Guide - Practice Questions

Study Guide - Flashcards