Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
14 Cards in this Set
- Front
- Back
|
What are the 4 Ions responsible for membrane Potential?
|
Na+, K+, Cl-, and A-
|
|
|
What is A-?
|
A- are negative proteins impermeable to the cell that used to be amino acids.
|
|
|
What ions are inside the cell? outside the cell?
|
Na+ and Cl- are outside the cell. K+ and A- are inside the cell. Membrane is 50-75x more permeable to K+ than to Na+
|
|
|
Electrical gradient for Na+ and K+ will always be where? their concentration gradients will move where?
|
The electrical gradient for both will move inside the cell. the concentration for na will move inside and k will move outside.
|
|
|
For every __ K+ moved into the cell, __ Na+ are moved out.
|
2 K+ moved in, 3Na+ are moved out.
|
|
|
EK+? ENa+? what does + or negative represent?
|
Ek= -90
Ena=+60 The polarity of excess charge on the inside of the membrane. |
|
|
In a hyp. cell where K channels are open only what is the process?
|
K+ will move along its concentration gradient out of the cell. Its electical gradient will move it back in due to opposite charges (outside more +, inside more -). K still moving out because of concentration gradient but eventually becomes weaker than elec force and they become equal and opposite and movement stops when Ek=vm.
|
|
|
In a hyp. cell where Na channels are open what is the process?
|
Na will move along it's concntration gradient into the cell. It's electrical gradient pushed it out of the cell. Na still moving out due to conc. gradient over time it becomes weaker than elec. and eventually they become equal and movement stops when Ena=vm
|
|
|
RMP=0 and both na and k channels open. process?
|
both move along their concentration gradients; thus na moves in and k moves out. because more k is moved out it makes the outside more positive which creates a negative rmp which causes and electrical force and both ka and na are attracted inside and move in. concentration is still moving k out and na in. k flow slows and na speeds up. when rmp =-70 koutflow=nainflow.
|
|
|
cell must maintain concentration gradient ____. to counteract it there are _____.
|
na/k pump. na/k leak channels.
|
|
|
E potential for an ion=
|
61(log Coutside/Cinside)
|
|
|
What establishes and what maintians the RMP?
|
leak establishes and na/k maintains
|
|
|
why does k leak out of the cell?
|
because it's at -70 but trying to reach -90
|
|
|
What are the different types of active and passive transports used in membrane potential.
|
1.diffusion of na and k through leak channels= passive
2. active= na/k pump. |
