biol 3410 10/29

During the contraction phase of a twitch contraction, __________ binds to troponin.

Calcium

In the contraction phase, __________ changes configuration to reveal the active site.

Tropomyosin

The formation of __________ occurs during the contraction phase of a twitch contraction.

Cross bridges

During the contraction phase, a __________ ensues after cross bridges are formed.

Power stroke

In the contraction phase of a twitch contraction, thin filaments slide toward the __________.

Z disc

During the latent phase of a twitch contraction, action potential spreads throughout the __________.

sarcolemma

Calcium moves out of the sarcoplasmic reticulum through __________ channels.

voltage-gated

The detachment of myosin cross bridges is triggered by __________ binding to the myosin head.

ATP

The timing of a twitch contraction occurs __________ the action potential.

after

ADP can borrow a phosphate group from __________ molecule to become ATP.

creatine phosphate

The fastest energy producing pathway is the __________ system.

phosphagen

A motor unit is defined as all of the skeletal muscle fibers that are innervated by a __________ motor neuron.

single

The contraction of a whole muscle structure depends on the __________ of motor units being recruited.

number

In wave summation, more frequent stimulation leads to a __________ contraction.

more forceful

Isotonic contractions occur when the muscle develops tension and __________ a load.

moves

In an __________ contraction, the muscle develops tension but does not change length.

isometric

Slow oxidative fibers are also called __________ fibers due to their red color.

red

Muscle fibers in a motor unit are all of the __________ type.

same

The calcium for smooth muscle contraction mainly comes from the __________ fluid.

extracellular

Calcium binds to __________ in smooth muscle to enable contraction.

calmodulin