AAMC SA BS Q85

[Oh_Gee]

my reasoning for choice C was that if there's more positive charges in the the matrix then won't that help repel H+ into the intermembrane space. why is that wrong?

 

[Oh_Gee]

bump
help please

 

[justadream]

@Oh_Gee
The H+ are pumped out of the matrix (using active transport). They don't leave easily passively (since they are charged and the inner membrane only lets non-charged stuff pass). That is why C is wrong.

 

[Oh_Gee]

@Oh_Gee
The H+ are pumped out of the cytosol (using active transport). They don't leave easily passively (since they are charged and the plasma membrane only lets non-charged stuff pass). That is why C is wrong.

wait pumped out of cytosol?

 

[justadream]

@Oh_Gee

Sorry, I meant mitochondrial matrix and inner membrane.

 

[Oh_Gee]

@Oh_Gee
The H+ are pumped out of the matrix (using active transport). They don't leave easily passively (since they are charged and the inner membrane only lets non-charged stuff pass). That is why C is wrong.

i get that H+ has to be actively transported out of the matrix b/c they don't leave easily passively, but wouldn't adding more + ions to the matrix make it easier for them to leave since there's now a new gradient

 

[justadream]

@Oh_Gee

I think gradients only apply when you think about passive transport.

Think about a filter that can only let proteins smaller than 5 [insert random units here] pass.

Even if you have a HUGE gradient for a protein that is a size of 20 [insert units], the protein still won't be able to pass through passively.