Muscle Tissue and contraction Physiology

Front

What is the sarcolemma?

Back

The membrane that surrounds a muscle fiber.

Front

What is the motor end plate?

Back

A modified area of the muscle fiber membrane at which a synapse occurs; a single muscle fiber only has one.

Front

What do neurotransmitters do in muscle contraction?

Back

They transmit signals across the synapse to initiate muscle contraction.

Front

What happens to actin filaments when a muscle is relaxed?

Back

They are far apart from each other.

Front

How does a muscle cell relax?

Back

ATP allows myosin to release its hold on actin.

Front

What is the role of calcium in muscle contraction?

Back

Calcium binds to troponin, causing a conformational change that allows myosin to bind to actin.

Front

Define myofibril.

Back

A long, thread-like structure made up of sarcomeres, responsible for muscle contraction.

Front

What is a sarcomere?

Back

The basic contractile unit of muscle tissue, defined by the area between two Z lines.

Front

What is the function of the sarcoplasmic reticulum?

Back

It stores and releases calcium ions during muscle contraction and relaxation.

Front

What is the role of ATP in muscle contraction?

Back

ATP provides the energy required for myosin to pull actin filaments during contraction.