Sarcomere Review

Front

What is a sarcomere?

Back

The sarcomere is the basic structural and functional unit of muscle tissue, responsible for muscle contraction.

Front

What does the I band represent in a sarcomere?

Back

The I band is the region of a sarcomere that contains only thin filaments (actin) and is lighter in appearance.

Front

What is the A band in a sarcomere?

Back

The A band is the dark region of a sarcomere that contains both thick (myosin) and thin (actin) filaments.

Front

What is the H zone?

Back

The H zone is the central part of the A band where there are only thick filaments (myosin) and no thin filaments (actin).

Front

What is the Z disc?

Back

The Z disc is a structure that defines the boundaries of a sarcomere and anchors the thin filaments.

Front

What is the M line?

Back

The M line is the middle line of the sarcomere that anchors the thick filaments (myosin) in place.

Front

How do sarcomeres contribute to muscle contraction?

Back

Sarcomeres shorten during muscle contraction, pulling the Z discs closer together and causing the muscle to contract.

Front

What is the role of actin in muscle contraction?

Back

Actin is a thin filament that interacts with myosin to facilitate muscle contraction.

Front

What is the role of myosin in muscle contraction?

Back

Myosin is a thick filament that pulls on actin filaments to cause muscle contraction.

Front

What happens to the I band during muscle contraction?

Back

The I band decreases in size as the sarcomere shortens during contraction.