4.1-4.5

Question 1

Are these ions negatively or positively charged?

Answer 1

Both potassium and sodium ions carry a single positive charge

Question 2

What is the resting potential of neurons?

Answer 2

-70 millivolts(mV). Potential charge inside the neuron is 70mV less than outside the neuron

Question 3

Describe the difference of polarization in reference to the membrane potential

Answer 3

Membrane potential is negative

The inside is more negative than outside

Question 4

Describe the difference of depolarized in reference to the membrane potential

Answer 4

Makes membrane potential less negative which means that it is more likely to fire

Question 5

Describe the difference of hyperpolarization in reference to the membrane potential

Answer 5

Makes membrane potential more negative which means that it is less likely to fire

Question 6

Describe distribution of Na+ and K+ ions when neuron is at rest

Answer 6

Sodium ions are outside neuron and potassium ions are greater inside neuron

Question 7

__________ are generated at the axon hillock, the structure at the junction between the cell body and the axon

Answer 7

Action Potentials

Question 8

Describe the difference between EPSPs and IPSPs

Answer 8

EPSPs: depolarization which means more likely to fire. Makes membrane potential less negative

IPSPs: hyperpolarizations which means less likely to fire. Makes membrane potential more negative

Question 9

EPSPs

Answer 9

Excitatory Postsynaptic Potentials

Question 10

IPSPs

Answer 10

Inhibitory Postsynaptic Potentials

Question 11

In order to generate an action potential, the ____ must be reached in the _____

Answer 11

• Threshold of Activation

* Axon Initial Segment

Question 12

What are the two ions that are of interest in understanding the resting potential of neurons?

Answer 12

Sodium Ions (Na+) and Potassium Ions(K+)