Question 1

Which structure in the sarcomere is responsible for anchoring the thin (actin) filaments and marks the boundary between adjacent sarcomeres?

Accepted Answer

Z disc

Question 2

What is the primary function of the A band in a sarcomere?

Accepted Answer

It marks the region where thick and thin filaments overlap.

Question 3

During muscle contraction, which region of the sarcomere shortens the most?

Accepted Answer

I band

Question 4

If a mutation caused the M line to be absent in a muscle cell, which of the following would most likely be affected?

Accepted Answer

Anchoring of thick (myosin) filaments

Question 5

Which of the following best describes the H zone in a sarcomere?

Accepted Answer

It is the region containing only thick filaments and no thin filaments.

Question 6

A patient with a genetic disorder has sarcomeres that lack Z discs. Which of the following would most likely be impaired?

Accepted Answer

Ability to anchor thin filaments

Question 7

Which of the following correctly matches the band or zone with its filament composition?

Accepted Answer

H zone: only thick filaments

Question 8

If the length of the sarcomere is $$2.5\ \mu m at $$rest and shortens to $$2.0\ \mu m$$ during contraction, what is the change in sarcomere length?

Accepted Answer

$$0.5\ \mu m$$

Question 9

Which of the following statements about the I band is correct?

Accepted Answer

It contains only thin filaments and is bisected by the Z disc.

Question 10

Which of the following best describes the arrangement of myosin and actin filaments within a sarcomere?

Accepted Answer

Actin filaments are anchored to the Z disc, and myosin filaments are anchored to the M line.

Question 11

Which region of the sarcomere remains the same length during muscle contraction?

Accepted Answer

A band

Question 12

A muscle biopsy reveals a disruption in the alignment of the Z discs. Which of the following is most likely to be affected?

Accepted Answer

The ability of the muscle to contract efficiently

Lab 5 Study Guide: Articulations, Muscle Anatomy, and Muscle Functions

Study Guide - Practice Questions