ion channels

Question 1

what are ion channels?

Answer 1

transmembrane proteins that form water filled pores through which ions in aqueous solution can flow down their electrochemical gradient

Question 2

structural requirement for any ion channel?

Answer 2

a pore, selectivity filter, a sensor, one or more gates

Question 3

is flow through ion channels passive or active?

Answer 3

passive

Question 4

what is the electrochemical driving force?

Answer 4

the difference between the membrane potential (Vm) and the equilibrium potential (Eeq) for that ion

Question 5

is membrane depolarisation inhibitory or excitatory?

Answer 5

excitatory

Question 6

what are dendrites?

Answer 6

branched processes that receive information from other neurons

Question 7

what does the cell body (soma) do?

Answer 7

contains the nucleus, drives maintenance and metabolism. integrates the information received by dendrites.

Question 8

what threshold do voltage dependent calcium channels open?

Answer 8

-30mV

Question 9

does calcium entry depolarise or hyperpolarise a cell?

Answer 9

depolarise

Question 10

are K channels opening inhibitory or excitatory?

Answer 10

inhibitory

Question 11

are sodium channels opening inhibitory or excitatory?

Answer 11

excitatory

Question 12

are calcium channels opening inhibitory or excitatory?

Answer 12

excitatory

Question 13

are chloride channels opening inhibitory or excitatory?

Answer 13

inhibitory

Question 14

how are ion channels classified?

Answer 14

description of their physiological properties, pharmacological basis, structure