Muscle Contraction

Question 1

What is the basic contractile unit of a skeletal muscle called?

Answer 1

Sarcomere

Question 2

True or False: Skeletal muscle contraction is voluntary.

Answer 2

True

Question 3

Fill in the blank: The protein that binds to calcium ions during muscle contraction is called __________.

Answer 3

Troponin

Question 4

What are the two main types of protein filaments in a sarcomere?

Answer 4

Actin and Myosin

Question 5

Which molecule provides the energy for muscle contraction?

Answer 5

ATP (Adenosine Triphosphate)

Question 6

In muscle contraction, what happens to the length of the sarcomere?

Answer 6

It shortens.

Question 7

What is the role of the neuromuscular junction in muscle contraction?

Answer 7

It transmits nerve impulses to muscle fibers, triggering contraction.

Question 8

Multiple Choice: Which ion is crucial for initiating muscle contraction? A) Sodium B) Potassium C) Calcium D) Magnesium

Answer 8

C) Calcium

Question 9

What is the sliding filament theory?

Answer 9

It describes how actin and myosin filaments slide past each other to produce muscle contraction.

Question 10

True or False: Muscle fibers can contract without the presence of calcium ions.

Answer 10

False

Question 11

What structure wraps around muscle fibers and stores calcium ions?

Answer 11

Sarcoplasmic reticulum

Question 12

Short Answer: Name one type of skeletal muscle fiber.

Answer 12

Type I (slow-twitch) or Type II (fast-twitch)

Question 13

Fill in the blank: The motor neuron releases __________ at the neuromuscular junction to stimulate muscle contraction.

Answer 13

Acetylcholine

Question 14

What happens during the power stroke in muscle contraction?

Answer 14

Myosin heads pull actin filaments toward the center of the sarcomere.

Question 15

Multiple Choice: Which of the following is NOT a phase of muscle contraction? A) Latent phase B) Contraction phase C) Relaxation phase D) Expansion phase

Answer 15

D) Expansion phase