Understanding Action Potentials

The cell responsible for generating electrical signals in the nervous system is the (a)   . It receives information from its ​ (b)   and then the ​ (c)   integrates the information. The resulting electrical signal is then transmitted along the ​ (d)   until it reaches the ​ (e)   , which transmit the information to the next cell.

• neuron
• dendrites
• cell body
• axon
• axon terminals

What is the electrical signal that is generated by neurons known as?

What are the main ions that help transmit an action potential? (Choose all that apply)

• Sodium

• Potassium

• Chloride

• Iodide

• Calcium

In a resting neuron, the concentration of (a)   ions is ​ (b)   outside of the cell than the concentration of ​ (c)   ions .

• sodium
• higher
• potassium

Which describes the distribution of charges across the membrane of a neuron at rest

• More positive charges outside of the cell than inside

• More negative charges outside of the cell than inside

• More positive charges inside of the cell than outside

• There is no difference between positive and negative charges

The difference in charge and ion concentration between the outside and inside of the neuron is known as the

What kind of ionic channel are sodium and potassium channels?

• Ligand gated ion channels

• Mechanically gated ion channels

• Voltage gated ion channels

• Light gated ion channels

When the sodium-potassium pumps are activated, they

• pump 3 sodium ions into the cell, and 2 potassium ions out of the cell

• pump 2 sodium ions out of the cell, and 3 potassium ions into the cell

• pump 2 sodium ions into the cell, and 3 potassium ions out of the cell

• pump 3 sodium ions out of the cell, and 2 potassium ions into the cell

What is the threshold that the membrane potential needs in order to fire an action potential?

• -55 mV

• -70 mV

• 0 mV

• 30 mV

Running the ion pumps requires energy to move molecules against their concentration gradients. What is that source of energy?

• ATP

• GTP

• Glucose

• Lactose