Question

Can someone explain the sodium potassium pump - how many sodiums and potassiums are taken/given? (SO confused on this and have an exam in a few hours!!!)

Answer 1

3 Na+ are given (from inside the cell to outside) and 2 K+ are taken (from outside the cell to inside).

Answer 2

Thank you so much! @jb1515g

Answer 3

Is that all you need to know about it?

Answer 4

I don't really understand the whole process of it, but I am definitely hoping that is all I need to know! I don't know why it is so confusing to me. I don't even understand the point of it. :( @jb1515g

Answer 5

The point of the sodium potassium pump is to maintain the concentration gradient of sodium and potassium in and around the cell to facilitate other processes, like the transportation of glucose, which helps the cells make energy. The ions are constantly trying to reach a state of equilibrium, where there are an equal number of Na+ and K+ on either side of the membrane, but that would be very bad for you. So the sodium-potassium pumps force Na+ and K+ against the gradient, so the ions never reach equilibrium.

Answer 6

Is there anything else you'd like to, or have to, know?

Answer 7

That is very helpful, thank you :) I am reviewing more stuff as we speak, so I will just tag your name if I have another Q! Really appreciate your willingness to help! I'm studying for a general cellular biology test.

Answer 8

Fun stuff. Yeah, if you need any more help, don't be afraid to ask.

Answer 9

Integrins... what exactly are they? As well as the extracellular matrix?

Answer 10

The extracellular matrix is a structure outside of the cells that, in a way, binds them together into tissue. It's like the framework that the cells are built on. It's what binds cells together so they aren't just randomly floating individual cells, but can actually form useful structures.

Integrins are the parts of the cells themselves that control how the cell attaches itself to the matrix. They are receptor proteins on the cellular membrane that act as a "go-between" for the cell they are attached to and the outside world of the extracellular matrix.

Answer 11

So the extracellular matrix is kind of like the cytoskeleton, but it on the outside of the cytoskeleton, right? & integrins are the y-shaped things that have specific types of proteins to get for each specific type of integrin? Is that correct or am I confusing this??

Answer 12

No, you're correct.

The extracellular matrix is to cells what the cytoskeleton is to different cellular structures. Remember the extracellular matrix isn't just outside the cytoskeleton, it's outside the cell itself. Thus, EXTRAcellular, meaning "located outside the cell."

And the integrins are the y-shaped things that bind to different proteins outside the cell to "grab hold" of the extracellular membrane and attach the cell to the larger network of cells.

Answer 13

Great- That summarized it up perfectly! Thanks again so much. Thanks for fully explaining your answers to my stupid Q's haha. Stressed college kid with a few hours of studying time before her exam. Sigh.

Answer 14

No problem. Any time.

Answer 15

One more final Q! Difference between hypertonic and hypotonic and isotonic? Need to know these front and backs because he often reverses the questions.

Answer 16

Alright, simple. Just think about the prefixes to understand:

Iso means equal. So an isotonic solution is one where the concentration of solutes is EQUAL.

Hyper means a lot, excess, above (think about a HYPERactive child, he is OVERactive) so that means in a hypertonic there is a HIGH concentration of solute.

Hypo is the opposite of hyper. It means below, less, deficient (think about things that are HYPO-allergenic, meaning low in allergens). So in a hypotonic solution, there is a LOW concentration of solutes.

If you keep in mind these definitions, plus the fact that every imbalance always wants to equalize itself, you should have no problem.

So if a cell is placed in a hypertonic solution, which means there is lots of solute (or you can think of it as less water. More solute concentration = less water), then water will tend to flow OUTof the cell (where it is more concentrated) to the area of less concentration (where there is more solute).

If a cell is placed in a hypotonic solution (one with less solute, or a higher concentration of water), then water will flow INTO the cell, trying to balance itself out, moving from an area of low solute concentration to one of high solute concentration.

If a cell is placed in an isotonic solution (remember, ISO means equal), then there will be no net flow one way or the other. It is at equilibrium.

Answer 17

I completely understand this now. You are a life saver.

Answer 18

No problem :)