Front

What is muscle tissue capable of?

Back

Muscle tissue is excitable, able to contract, and able to extend.

Front

What wraps muscles and what does it become at the ends?

Back

Muscles are wrapped by deep fascia, which runs off both ends of the muscle as a tendon that attaches the muscle to bone.

Front

What are muscle cells called?

Back

Muscle cells are called muscle fibers.

Front

What are myofibrils and what are they made of?

Back

Myofibrils are thread-like structures inside a muscle cell, made of filaments called actin (thin) and myosin (thicker), which are proteins.

Front

What is a nerve impulse called?

Back

A nerve impulse is called an action potential.

Front

What is a motor neuron?

Back

A neuron that leads to a muscle fiber is called a motor neuron.

Front

What is a synapse in muscle anatomy?

Back

A synapse is a small gap between the end of a motor neuron’s axon and the muscle fiber.

Front

What happens when an action potential reaches the end of an axon?

Back

A neurotransmitter called acetylcholine is released, which crosses the synapse and stimulates the muscle cell.

Front

What effect does acetylcholine have on muscle cells?

Back

Acetylcholine causes muscle cells to become charged (depolarized), leading myosin to grab and pull on actin.

Front

What is a motor unit?

Back

A motor unit consists of one motor neuron and all the muscle cells its axon branches touch and stimulate.