Muscular System

Cardiac muscle is only found where? 

• Lungs
• Heart
• Kidney's 
• Liver

What are the 3 types of muscles?

• Cardiac, smooth and skeletal
• Cardiac, skeletal, prime
• Flexion, extension, smooth
• Skeletal, smooth, stringy

What is a voluntary muscle?

• You have control over the muscle 
• You have no control over the muscle
• Muscle works automatically
• Muscles fuse together

Movements that you cannot control

• Strain
• Sprain
• Voluntary
• Involuntary

Movements that you choose to control

• Cramp
• Voluntary
• Strain
• Involuntary

These muscles are found in your organs

• Skeletal
• Smooth
• Rough
• Cardiac

These muscles are attached to your bones

• Skeletal
• Smooth
• Rough
• Cardiac

When a muscle contracts, it _______

• gets longer
• gets shorter
• gets thinner
• grows hair

At what point does a muscle contraction occur?

• At the same moment sodium (Na) depolarizes the cell.

• As the action potential travels down the axon of a neuron.

• As soon as myosin binds to actin and pulls it towards the center of the sarcomere.

• As soon as calcium binds too troponin on an actin molecule.

Why is calcium absolutely essential for muscle contraction?

• Calcium makes bones stronger, which means muscles also get stronger.

• Calcium binds to troponin, simply exposing the myosin binding site for actin.

• Calcium inhibits muscle contraction because it depolarizes the cell.

• Calcium is needed in order for ATP to attach to myosin heads, which causes contraction.