Resting Membrane Potential
Call Kai
Learn
Practice Test
Spaced Repetition
Match
Flashcards
Knowt Play1/32
There's no tags or description
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced | Call with Kai |
|---|
No analytics yet
Send a link to your students to track their progress
33 Terms
What creates the electrical properties of neurons?
Ionic concentration differences + membrane permeability
What is membrane potential?
Voltage (charge difference) across the plasma membrane
What causes membrane potential?
Separation of positive and negative charges
What is a cation?
Positively charged ion
What is an anion?
Negatively charged ion
Basic charge rule?
Like charges repel, opposite charges attract
What is resting membrane potential (RMP)?
Voltage across membrane when neuron is not sending signals
Typical RMP value in neurons?
~ −70 mV
Why is it negative?
Inside of the cell is more negative than outside
Which ions are higher outside the cell?
Na⁺, Cl⁻, Ca²⁺
Which ions are higher inside the cell?
K⁺ and negatively charged proteins
Where does the charge difference occur?
Just inside and just outside the membrane
What does the Na⁺/K⁺ pump do?
Maintains ion gradients
What is the pump ratio?
3 Na⁺ out, 2 K⁺ in
What kind of transport is it?
Active transport (requires ATP)
Why is the pump important?
Keeps Na⁺ high outside and K⁺ high inside
What are leak channels?
Always-open ion channels
Which leak channels are most common?
Potassium (K⁺) channels
What are gated channels?
Open/close in response to stimuli
Types of gated channels?
Ligand-gated
Mechanically gated
Voltage-gated
What determines permeability?
Number of channels
Ion size
Channel typ
What drives K⁺ movement out of the cell?
Concentration gradient (high → low)
What happens when K⁺ leaves?
Leaves positive charge outside → inside becomes negative
Why are proteins important?
They are negative and trapped inside (cannot cross membrane)
What pulls K⁺ back into the cell?
Electrical gradient (attraction to negative interior)
When is RMP established?
When K⁺ movement out = K⁺ movement in
Does ion movement stop completely?
No, but net movement = 0
Why is the inside negative?
K⁺ leaves
Negative proteins remain
More positive charge outside
What contributes MOST to RMP?
Potassium (K⁺) movement
Why does K⁺ dominate?
More K⁺ leak channels than Na⁺ channels
RMP depends on what 2 main factors?
Na⁺/K⁺ pump
Membrane permeability
Inside vs outside charge?
Inside = negative, Outside = positive
Main ion responsible for RMP?
Potassium (K⁺)