Muscular System Review

The functional connection between a neuron and a skeletal muscle fiber is a

• Synapse

• Fascia

• Dendrite

• Crossbridge

Contractile unit of a muscle which is also the functional unit of a muscle is ...

• sarcomere

• motor unit

• fascicle

• myofibril

The cytoplasm of a muscle cell is called the

• Sarcoplasmic Reticulum

• Sarcomere

• Sarcoplasm

• Sarcolemma

The type of filament that has moveable heads.

• L band

• Thin band

• Myosin filaments

• light band

When a muscle contracts, it _______

• gets longer

• gets shorter

• gets thinner

• grows hair

Once ACH binds to receptor cells on the sarcolemma, what takes place?

• Sarcolemma becomes temporarily permeable to sodium.

• The muscle contracts.

• Calcium is pumped into the axon terminal.

• Synaptic vesicles move to the end of the terminal.

given the following events:

1.acetycholine broken down

2.acetylcholine moves across the synaptic cleft

3.action potential reaches the terminal branch (presynaptic terminal)

4.acetylcholine combines with a receptor molecule on a skeletal muscle (postsynaptic membrane)

5.action potential produced in skeletal muscle cell

Choose the arrangement that lists the events in the order the occur at a neuromuscular injunction

• 2,3,4,1,5

• 3,2,4,5,1

• 3,4,2,1,3

• 4,5,2,1,3

What happens to an action potential once it reaches the synaptic cleft?

• It causes the neurotransmitter ACH to be released

• It diffuses across the synaptic cleft

• It changes the membrane potential of the muscle cell

• It provides energy for myosin to bind to actin

Myofibrils are composed primarily of:

• Myofilaments

• Fascicles

• Myofibers

• Muscle cells

During muscle contraction, myosin crossbridges attach to which active sites?

• Myosin

• Actin

• Thick Filaments

• Troponin