A&P Unit 6 Workbook: Muscular System

Front

What is the insertion in the muscular system?

Back

The insertion is the place where a tendon attaches the muscle to the moveable end of the bone.

Front

What is the role of actin in muscle contraction?

Back

Actin is a thin filament that slides past myosin during contraction.

Front

What is the smallest functional contractile unit of muscle fiber?

Back

The sarcomere.

Front

Which ion is released from the sarcoplasmic reticulum during muscle contraction?

Back

Calcium.

Front

What is the function of the sarcoplasmic reticulum in muscle contraction?

Back

It stores and releases calcium ions.

Front

What is the origin in the muscular system?

Back

The origin is the point where a tendon attaches the muscle to the stationary end of the bone.

Front

What are myofibrils?

Back

Myofibrils are long, thread-like structures within muscle fibers that contain the contractile proteins actin and myosin.

Front

What is the role of myosin in muscle contraction?

Back

Myosin is a thick filament that forms cross-bridges with actin to facilitate muscle contraction.

Front

Define neuromuscular junction.

Back

The neuromuscular junction is the synapse or connection point between a motor neuron and a muscle fiber.

Front

What is the role of acetylcholine in muscle contraction?

Back

Acetylcholine is a neurotransmitter that is released at the neuromuscular junction to stimulate muscle contraction.