BIO 161 EXAM 3 QUESTIONS AND CORRECT ANSWERS
The neuromuscular junction (or synapse) involves with of the following two cell types? -
(answers)neuron:skeletal muscle
Which of the following neurotransmitters are released at the neuromuscular junction? -
(answers)acetylcholine
What type of channels bind to acetylcholine in the post-synaptic (muscle cell) membrane? -
(answers)chemical (ligand)-gated
-Acetylcholine is a chemical and it provides the "key" to open channels in the muscle cell membrane.
Receptors for acetylcholine are located in the motor end plate of the muscle cell. - (answers)True
-By definition, the motor end plate is the part of the muscle cell membrane that forms a synapse with
the somatic motor neuron.
What is the major role of acetylcholine esterase? - (answers)To break down acetylcholine in the synaptic
cleft.
-Acetylcholine esterase enzymatically breaks down acetylcholine from the cleft to STOP the signal from
the motor neuron. This is an important step that leads to muscle relaxation.
Transverse tubules are extensions of which of the following organelles - (answers)sarcolemma
If calcium protein channels in the sarcoplasmic reticulum (SR) open in response to an action potential,
calcium diffuses out of the sarcoplasm and into the SR. - (answers)False
The neuromuscular junction (or synapse) involves with of the following two cell types? -
(answers)neuron:skeletal muscle
Which of the following neurotransmitters are released at the neuromuscular junction? -
(answers)acetylcholine
What type of channels bind to acetylcholine in the post-synaptic (muscle cell) membrane? -
(answers)chemical (ligand)-gated
-Acetylcholine is a chemical and it provides the "key" to open channels in the muscle cell membrane.
Receptors for acetylcholine are located in the motor end plate of the muscle cell. - (answers)True
-By definition, the motor end plate is the part of the muscle cell membrane that forms a synapse with
the somatic motor neuron.
What is the major role of acetylcholine esterase? - (answers)To break down acetylcholine in the synaptic
cleft.
-Acetylcholine esterase enzymatically breaks down acetylcholine from the cleft to STOP the signal from
the motor neuron. This is an important step that leads to muscle relaxation.
Transverse tubules are extensions of which of the following organelles - (answers)sarcolemma
If calcium protein channels in the sarcoplasmic reticulum (SR) open in response to an action potential,
calcium diffuses out of the sarcoplasm and into the SR. - (answers)False
