Nervous System Practice Test

Which term refers to the difference in electrical charges on either side of a cell membrane?

• membrane potential
• electricity
• signal transduction
• negativity

What is a synapse?

• The space between the axon of one neuron and the cell that is receiving a signal
• a chemical signalling molecule
•  a type of neuron
• a part of the axon

Given the steps shown below, which of the following is the correct transmission sequence at a chemical synapse?

1. Neurotransmitter binds with receptor

2. Sodium ions rush into neuron’s cytoplasm

3. Action potential depolarizes the presynaptic membrane

4. Ion channel opens to allow particular ion to enter cell

5. Synaptic vesicles release neurotransmitter into the synaptic cleft

• 4-3-1-2-5

• 2-3-5-4-1

• 1-2-3-4-5

• 3-2-5-1-4

Lidocaine is a local anesthetic that works as a temporary pain reliever. Lidocaine works by binding to voltage sensitive Na+ gates on pain receptors and prevents the gates from opening. Which of the following best describes why Lidocaine is an effective anesthetic?

• Lidocaine limits sodium influx, which increases the production of presynaptic vesicles.

• Lidocaine increases sodium influx, which stimulates the propagation of the action potential.

• Lidocaine decreases sodium influx, which decreases the propagation of the action potential.

• Lidocaine increases sodium influx, which decreases the release of neurotransmitters.

The diagram below graphs an action potential. Use the Roman Numerals to indicate your answer to the following questions.

A neuron that is not conducting an action potential would have a membrane potential that is most like the value at

• I and II

• I and III

• I and IV

• II and III

Tags

NGSS.HS-PS2-5

The diagram below graphs an action potential. Use the Roman Numerals to indicate your answer to the following questions.

Open sodium channels allow positively charged sodium ions to enter the neuron. Which Roman Numeral on the graph indicates the time during which the sodium channels are open?

• I

• II

• III

• IV

Tags

NGSS.HS-PS2-5

When an action potential is generated, the inside of the membrane becomes

• positive relative to the outside
• negative relative to the outside
• polarised
• filled with potassium ions

Threshold stimulus means that

• the size of the action potential does not change
• only one impulse is conducted at a time
• a certain level of stimulus is required to generate an action potential
• the membrane becomes repolarised quickly after an action potential passes

Which part of a neuron releases neurotransmitters?

• Axon

• Dendrites

• Axon terminals

• Soma

Which ion flows into a neuron to initiate an action potential?

• Sodium

• Potassium

• Chloride

• Calcium