[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 65 KB, 600x792, woman.jpg [View same] [iqdb] [saucenao] [google]
2180579 No.2180579 [Reply] [Original]

can someone help explain what a Reversal potential is in layman's terms? as part of physiology to do with equilibriums of solutes in a semi-permeable solute

thanks in advance.

>> No.2180600
File: 46 KB, 470x383, 1268672047480.jpg [View same] [iqdb] [saucenao] [google]
2180600

please help. Are there any physiologists out there?

>> No.2180612
File: 7 KB, 246x344, r3626269604.jpg [View same] [iqdb] [saucenao] [google]
2180612

please help a poor uni student with a final tomorrow =)

>> No.2180628

How layman? I can go pretty fucking far.

An any soluble compound will move down a concentration gradient, gradually reaching equilibrium within the solution, such as when making a cup of tea (too patronising?)

Ions also have a charged element to them as well and as like charges repel, it makes the diffusion gradient substantially more complex with two variables rather than one.

The reversal potential is the voltage across the membrane at which an ion is in equilibrium with both charge and concentration balancing each other on both sides. Slightly changing the potential from this point will cause the ions to net flow across the membrane.

>> No.2180638

someone shoulda gone to class

also, FUCKING WIKIPEDIA. Jesus christ people I just googled "reversal potential" and the first response is a perfectly detailed wikipedia article. Does your mother call to wake you up in the morning, or do you just live in her basement?

>> No.2180647

>>2180638
i read that article and i didn't help.
and i've been to class but the prof. didn't cover it in lecture and it's only in her slides. barely.

>> No.2180671

>>2180628
thanks

but how are you able to make assumptions of another cell based upon the resting potential and the threshold?

i.e. the presynaptic neuron fires upon the post synaptic making an excitatory response.
the resting potential = -70mv and the threshold of the presynaptic is -50mv
you can assume that the post has a v reversal of greater than -50mv.
how are you able to reach that conclusion?

>> No.2180701 [DELETED] 
File: 29 KB, 470x324, African Painted Dog.jpg [View same] [iqdb] [saucenao] [google]
2180701

>>2180671
Oh fuck, I've forgotten how to do this, but there's a way that it falls out from Goldman equation (or Nernst, which is really just simplified Goldman), I think.

>> No.2180711

>>2180701
The questions was from a midterm and it was a true/false
you didn't need to use goldman-katz or nernst.
and i can't think with numbers, i need like a logical explanation

>> No.2180780

>>2180671
Neurons use voltage dependent Na+ channels during depolarisation, when one triggers, the Na+ ions it lets in further increases the membrane potential, opening more channels - the principal of the all or nothing rule.

We can infer the post-synaptic knob reversal potential is 50mV for Na+ as this is threshold and the point at which channels start openning and allowing Na+ to flood in.

That's what I assume anyway. I fucking hate electrophysiology.

>> No.2180786

>>2180780
>edit
-50mV

>> No.2180817

>>2180780

thanks!

i got the answer