Muscle Structure & Physiology

The smallest unit of contraction is the

• Myosin

• Sarcomere

• Myofibril

• Fascicle

Which type of muscle tissue is involuntary?

• Skeletal muscle

• Cardiac muscle

• Smooth muscle

What is not a special characteristic of muscle cells?

• Contractility

• Elasticity

• Excitability

• Agility

The arrow is pointing to

• The Z disc

• The I band

• The thin filament

• The H zone

Which muscle characteristic allows the muscle to return to resting length after contraction?

• Contractility

• Excitability

• Elasticity

• Tension

What protein makes up the thick filaments?

• Troponin

• Tropomyosin

• Myosin

• Actin

What is the name of the location where the neuron and muscle fiber meet?

• Sarcoplasm

• Sacolemma

• Neuromuscular junction

• Axon terminal

What is the name of the neurotransmitter that is released from the neuron to the sarcolemma?

• Acetylcholine

• Acetone

• ATP

• Calcium

Which of these occurs first during a muscle contraction?

• The nerve signal reaches the neuromuscular junction

• Ach is released and opens Na ion channels

• The sarcomere shortens

• The myosin binds to the actin

What is the name give to the thin protein filaments within the muscle contractile unit?

• Myosin
• Actin
• Myoglobin
• Haemoglobin