Question 1

Which of the following best describes the structural difference between skeletal, cardiac, and smooth muscle fibers as seen under a microscope?

Accepted Answer

Smooth muscle fibers are small, lack striations, and have a single nucleus.

Question 2

Which signal initiates contraction in all three types of muscle tissue?

Accepted Answer

An increase in intracellular calcium ion concentration ($$[Ca$$^{2+}$$]_{in})$$

Question 3

Which muscle type is under voluntary control and what is the pathway for its activation?

Accepted Answer

Skeletal muscle; somatic nervous system

Question 4

What is the primary function of antagonistic muscle groups?

Accepted Answer

To allow for both flexion and extension of a joint by having opposing actions

Question 5

Which of the following is a characteristic unique to cardiac muscle fibers?

Accepted Answer

Presence of intercalated disks

Question 6

A patient has a disorder affecting the autonomic nervous system. Which muscle type is most likely to be directly affected?

Accepted Answer

Smooth muscle

Question 7

Which of the following best explains why skeletal muscle fibers are multinucleated?

Accepted Answer

They are formed by the fusion of multiple precursor cells during development.

Question 8

Which of the following is true regarding the arrangement of proteins in a sarcomere?

Accepted Answer

The striated appearance of muscle fibers is due to the regular arrangement of actin and myosin filaments.

Question 9

Which of the following best describes the role of the somatic motor neuron in skeletal muscle contraction?

Accepted Answer

It initiates an action potential in the muscle fiber, leading to contraction.

Question 10

Which of the following is a correct sequence of structures from largest to smallest in skeletal muscle organization?

Accepted Answer

Skeletal muscle → Muscle fascicle → Muscle fiber

Question 11

A drug that blocks the function of intercalated disks would most directly affect which process?

Accepted Answer

The ability of cardiac muscle cells to synchronize contraction

Question 12

Which of the following best describes the control of smooth muscle contraction?

Accepted Answer

It is controlled by the autonomic nervous system and hormones.

Question 13

Which of the following statements about muscle contraction is correct?

Accepted Answer

All muscle types require ATP for contraction.

Question 14

During a biceps curl, which muscle acts as the flexor and which as the extensor?

Accepted Answer

Biceps is the flexor; triceps is the extensor.

Question 15

Which of the following best explains why cardiac muscle cells are branched?

Accepted Answer

Branching allows for rapid and coordinated contraction throughout the heart.

Question 16

Which of the following is a function of the connective tissue surrounding muscle fibers?

Accepted Answer

It transmits force generated by muscle fibers to tendons.

Question 17

A patient with a genetic mutation that prevents the formation of sarcomeres would most likely have which symptom?

Accepted Answer

Weakness in skeletal muscle contraction

Question 18

Which of the following best describes the role of the sarcolemma in muscle physiology?

Accepted Answer

It is the plasma membrane of a muscle fiber that conducts action potentials.

Question 19

Which of the following is a real-life example of smooth muscle function?

Accepted Answer

Constriction of blood vessels to regulate blood pressure

Muscle Physiology: Types, Structure, and Control

Study Guide - Practice Questions