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
