Muscle Contraction

__________ is attached to the Z line?

• myosin

• actin

• thick filament

• troponin

____________ attaches to actin to form the cross bridge.

• Troponin

• Tropomyosin

• Myosin

• Calcium

The H zone changes size during a muscle contraction.

• True

• False

The I band is labeled here as _______.

• AD

• AC

• BC

• AB

The A band is labeled here as _______.

• AD

• AC

• BC

• AB

The actin is labeled here as _______.

• AD

• AC

• BC

• AB

The myosin is labeled here as _______.

• BD

• AC

• BC

• AB

The Z line is labeled here as _______.

• BD

• AC

• AE

• AB

A sarcomere is labeled here as _______.

• BD

• BC

• AE

• AB

Which of the following occurs first in a muscle contraction cycle?

• Myosin head is placed in the cocked position

• Myosin head undergoes power stroke

• Myosin head pulls the actin filament towards the H zone

• Myosin head forms cross bridge