Question

in the sarcomere, the thick filaments are held in place by proteins located in a thickening within the a band called the

a line

z line

m line

i line

need help? review these concept resources.

rate your confidence to submit your answer.
high
medium
low

reading

© 2025 mcgraw hill. all rights reserved. privacy center terms of use

Explanation:

In a sarcomere, the M - line is a thickening within the A - band where proteins hold the thick filaments in place. The A - line is not a relevant structure in this context. The Z - line marks the boundaries of the sarcomere and separates I - bands from A - bands. The I - line is not a recognized structure in sarcomere anatomy.

Answer:

C. M line