EPSP, IPSP, Etc. (Tuesday)

Question 1

What is the purpose of EPSPs?

Answer 1

to depolarize the membrane to activate an action potential

Question 2

How do you get a fast action potential with a length constant?

Answer 2

you want the smallest amount of resistance (rm/ num of leak channels) and the largest amount of internal resistance (ri/thickness of dendrite)

Question 3

Which synapse can better depolarize with a length constant? One with a thin dendrite and many leak channels or the vice versa?

Answer 3

the latter since you can picture a tick hose with few holes gets more water out than the former

Question 4

What does spatial summation do?

Answer 4

it uses the SUMMATION of mini potentials in separate dendrites to create a large action potential

Question 5

What does temporal summation do?

Answer 5

it uses the spacing of mini potentials in a single dendrite to trigger an action potential

Question 6

How do you get a fast action potential with a time constant?

Answer 6

you want both membrane resistance and membrane capacitance (cm/surface area of neuron) to be large

Question 7

What will depolarize better? Three spikes of mini potentials that are closer together and spread out or the vice versa?

Answer 7

the former since they summate in a smaller time frame

Question 8

What is the purpose of IPSPs?

Answer 8

they hyper polarize the the membrane by making it more negative which then reduces/cancels out the action potential