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Flashcards in Membrane Potential and Excitation Deck (72)
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1

Separation of positive and negative charges is what type of energy?

Potential

2

Energy that allows separated charges to move freely. This flow is called current, amps.

Kinetic Energy

3

The force which slows down current flow.

Resistance

4

A substance which inhibits current flow

Insulator

5

A substance which promotes current flow

Conductor

6

Current = ?

V/R

7

Why does current flow occur in living systems?

Ions flow!

8

Where do they flow across? (What is the insulator of charge separation?)

Membrane - separates charges

9

The integral, transmembrane proteins which serve as conductors in living systems that allow ions to flow when open

Channels

10

Leakage channels that are typically always open that allow ions to flow through them

Passive Channels

11

Gated channels that only open when stimulated

Active Channels

12

Type of gated channel that is opened by a chemical . Opens when chemical binds to transmembrane protein/receptor to provide pathway for ions to flow inside or outside membrane

Chemically gated channel

13

Type of active channel that is opened by a change in potential energy, there is a change in the voltage distribution across membrane due to ions, which opens channel to allow ions to flow across membrane

Voltage Gated Channel

14

Current flow depends on two factors. What are they?

Electrical Charge Movement
Chemical Diffusion

15

Current flow factor where ions that are charged will move toward an area that contains an opposite charge

Electrical Charge Movement

16

Current flow factor where chemicals diffuse from an area of high concentration to low concentration

Chemical Diffusion

17

Together, electrical charge movement and chemical diffusion are known as...

Electrochemical Gradient

18

Flow of ions across membranes is controlled by this, which conducts the current and carries the kinetic energy used to do the work of the action potential

Electrochemical Gradient

19

It is created by unequal concentrations of ions of both charges that exist in a narrow band around each side (cytoplasmic and extracellular) of the plasma membrane.

Resting Membrane Potential

20

Potential energy is created due to the chemical and electrical forces that develop across the membrane

Different ions, different concentrations of each ion, different charges on ions

Resting Membrane Potential

21

Charged separation is referred to as _________, it is the basis of all electrical conductivity of cells capable of conducting action potential

Polarization of the membrane

22

What are the units of charge separation?

What is the orientation (outside with respect to inside or inside with respect to outside?)

millivolts

Inside with respect to outside

23

What is typical cell membrane charge, or the resting membrane potential?

-70mV

24

Note: cell as whole is neutral, but separation of charges occurs where?

At the membrane

25

Specific ions separate themselves at different concentrations immediately around the membrane, creating (generation and maintenance of RMP)

Polarization

26

Na, K, Cl are capable or incapable of moving outside/inside the membrane?

Negatively charged proteins are fixed/capable of moving?

Capable

Fixed. Only positively charged ions can move.

27

Gnereates concentration difference for Na+ and K+, require ATP and translocate ions against concentration gradient

ATPase pump

28

How much NA and K are pumped in or out simultaneously of an ATPase pump?

3Na+ pumped out

2K pumped in

29

What type of port is the ATPase? How many ions are moving?

antiport, 5

30

There are many pumps in the plasma membrane which pump all the time

!