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All right.
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So in this example, we're going to talk about concentration gradients.
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So the concentration gradient is where you go from some area or space that has a high concentration of particles, chemicals, ions, whatever it is.
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And then you transport them to an area of a lower concentration.
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So you want your process, if it's going down a concentration gradient, to go from an area of high concentration to low concentration.
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So let's look at these examples.
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So let's look at first exocytosis.
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So we know that exocytosis is where the cell, this is one of your cells, it's going to, here's some of the organelles in it, there's the nucleus, something, some other things.
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It's going to take some particles that it has inside and it is going to actually eject them from itself.
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So what's going to end up happening is you have all of these particles that have gone from a high concentration within the cell to a low concentration outside the cell.
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It doesn't matter that at the end, the concentration is higher outside the cell.
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It's more about the process where it starts.
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So you have a high concentration inside the cell, but a low concentration outside.
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So this is following the concentration gradient.
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So let's also look at diffusion.
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So diffusion is pretty much just this high to low concentration concept.
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Let's say i have a box.
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And there's a lot of things in it, and it's closed, which is why they're all staying in there.
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But the second that i opened the box, all the kind of particles, a couple are going to stay in there, of course, but all the particles are going to kind of rush out.
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So we have an initial concentration inside the box that is high, and a low concentration outside of the box.
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So this is also following the gradient.
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So let's also look at facilitated transport.
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Facilitated transport is kind of very similar to diffusion, except we need a little bit of help.
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So facilitated, let's draw a cell membrane.
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So normally, if you have a particle and it wants to go in, some of them can't do that without some help.
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So what we're going to do is we're going to give them some help.
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So facilitated diffusion means that there's some sort of protein or molecule or something that's helping the molecule in question get in or out of cell.
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So let's say there's a bunch of molecules on the outside and they want to go in.
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Well, there are going to be able to go in because there's very little, if none, of the molecule inside...