4.2.1 and 4.2.5 Muscle Organization, Rules, and Contraction

Tiny chains of contractile units aligned end to end making up a muscle fiber

• sarcolemma

• myofibrils

• synaptic cleft

• sarcomere

Which of the following is the correct order of muscle tissue?

• fascicle, muscle fiber, myofibril, sarcomere, myofilament

• muscle fiber, fascicle, sarcomere, myofibril, myofilament

• sarcomere, muscle fiber, fascicle, myofibril, myofilament

• fascicle, muscle fiber, myofilament, myofibril, sarcomer

A neurotransmitter released from the end of a motor neuron that stimulates skeletal muscles

• acetylcholine (Ach)

• ATP

• cross bridges

• neuromuscular junction

The only energy source that can be used to directly power muscle activity

• acetylcholine (Ach)

• ATP

• cross bridges

• neuromuscular junction

The heads of the myosin myofilaments are called __ when they link the thick and the thin filament together

• acetylcholine (Ach)

• ATP

• cross bridges

• neuromuscular junction

Myosin protein

• sarcolemma

• sarcoplasmic reticulum

• thick filament

• thin filament

Actin, contractile protein

• sarcolemma

• sarcoplasmic reticulum

• thick filament

• thin filament

What is the function of calcium during a skeletal muscle contraction?

• connecting to a myofilament

• connecting to troponin

• connecting to myofibril

• connecting to myosin

What causes the force of the contraction?

• acetylcholine
• myosin moving 
• Calcium
• actin moving

What attaches a muscle to bone?

• Tissue

• Tendon

• Ligament

• Fascia