U3L3 Structure of a sarcomere

Front

What is a sarcomere?

Back

The basic contractile unit of muscle contraction.

Front

What happens to the H Zone during muscle contraction?

Back

The H Zone disappears.

Front

How many sarcomeres are typically found in a muscle fiber?

Back

The number can vary, but in this context, there are 5 sarcomeres shown.

Front

What does #1 represent in a diagram of a sarcomere?

Back

Sarcomere.

Front

What section does the #6 show in a sarcomere diagram?

Back

A Band.

Front

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

Back

Actin and Myosin.

Front

What is the function of the Z Disc in a sarcomere?

Back

It anchors the actin filaments and defines the boundaries of each sarcomere.

Front

What is the A Band in a sarcomere?

Back

The region that contains both actin and myosin filaments.

Front

What is the M Line in a sarcomere?

Back

The line that bisects the H Zone and anchors the myosin filaments.

Front

What is the role of myosin in muscle contraction?

Back

Myosin heads bind to actin filaments and pull them, causing contraction.