Secondary Active Membrane Transport - Video Tutorials & Practice Problems

Secondary Active Membrane Transport

Hey, guys, in this video, we're going to quickly revisit our map of the lesson on membrane transport, and we know that we're exploring the left most branches first. And we've already talked about molecular transport of small molecules, including passive transport. And we're currently exploring active transport. And we've already covered all of these branches here for primary active transport. And so now in our next video, we're going to explore this little branch over here for secondary active transport. And then after that, we'll talk about a very specific example of secondary active transport in the sodium glucose importer. So I'll see you guys in our next video to talk about secondary active transport.

Secondary Active Membrane Transport

in this video, we're going to talk more details about secondary active membrane transport. And so you might recall in our previous lesson videos, we briefly introduced secondary active membrane transport, and so we already have somewhat of an idea that secondary active transport is not directly driven by eight p hydraulics. ISS, like primary active transport ISS and instead, secondary active transport is actually directly driven by an electrochemical ion Grady int, and we'll be able to see that down below in our image when we get there. Now. However, what's really important to note is that although secondary active transport is not directly driven by a teepee, hydraulic sis, it is indirectly driven by a teepee. Hydraulics, ISS. And that's because secondary active transport is indirectly driven by primary active transport or P A. T. For short here. And so the reason that secondary active transport is indirectly driven by primary active transport and by 80 p i drawl. Icis is because electrochemical ion Grady INTs, which secondary active transport relies heavily on, are built by primary active transport or again P. A. T. Here for short for space purposes here, and so during secondary active transport. What we'll see is that it's really going to code transport two molecules at a time and so ions will be transported down or with their electrochemical Grady INTs from areas of high concentration, two areas of low concentration, whereas other molecules such as glucose or amino acids or things of that nature they will be transported against or up their concentration. Grady INTs from areas of low concentration to areas of high concentration. And so, if we take a look at our example image down below of secondary active transport. What I want you guys to notice is that over here on the left hand side, we're showing you guys primary active transport, as is labeled right here. And we can tell because a teepee hydraulics ISS is directly involved with the process of transporting this molecule here against its concentration ingredient from areas of low concentration, two areas of high concentration and then notice Over here on the right hand side of our image. We're showing you guys second dairy, active transport, and we can tell because notice that at p hydraulics, ISS is not directly involved with secondary active transport. However, it is again indirectly involved because it relies on primary active transport toe build up this electrochemical ion Grady int. And so this ion right here is able to diffuse across the membrane down its concentration greedy int from high tow low, which does not require energy. It is a passive X organic process. However, notice that as the red molecule is going from high to low, this other green molecule over here is being transported against its Grady int from an area of low concentration to an area of high concentration. And really, this is the transport part that requires energy. And so it's the energy released from this down flow movement off the ion from high to low that is powering the uphill movement, or the uphill, um, end organic process off, powering this molecule to be transported against its concentration, radiant from low, too high. And so we'll be able to see an example of secondary active transport and our next lesson. But for now, this here concludes our lesson on secondary active membrane transport, and we'll be able to get some practice applying these concepts in our next video. So I'll see you guys there

Secondary Active Membrane Transport Example 1

all right, so here we have an example problem that says the sodium potassium pump is an example of a system that uses primary active transport to set up conditions that can ultimately allow for secondary active transport. And then it says all of the following five answer options down below are true, except for which one. And so essentially, what this problem is asking us to do is to identify the false answer option. And so I'll write that here just as a reminder. And so when we take a look at Option A, it says that the sodium potassium pump is an anti porter fueled by the hydraulics is of a deep. And so you might recall from our previous lesson videos that the sodium potassium pump is an example of a P type 80 p ace. And because it is an 80 piece, it does involve the hydraulics of ATP, and it also pump sodium and potassium in opposite directions across the membrane, which makes it an anti porter. And so what we're saying here is the option. A is a true statement, and because it's true, it's not the false answer option that we're looking for so we can eliminate Option A now moving on to Option B here, it says that secondary active transport of glucose into cells moves glucose against its concentration, radiant and, of course, secondary or primary active transport. Because it is active and involves the use of energy in one way or another, it is going to be moving molecules against their concentration. Grady INTs. And so this here is also going to be a true statement. And so weaken market is true. And again, it's not the false answer option that we're looking for. So let's eliminate option B. So moving on option. See here It says that the sodium potassium pump exports sodium ions to the outside of the cell, establishing a concentration Grady Int for sodium and, of course, recall from our previous lesson videos on the sodium potassium pump that it does indeed export sodium ions. And the way that we remember that is that it's trying to get into club intracellular. But the bouncers are saying Nah, and so the n a. Here. Nah, you can't get into the South reminds us that it's going to be pumped to the outside of the cell and instead the pumpkin is gonna remind us that it's K plus that gets pumped in to the cell. And so what we're saying here is that option. See, here is also a true statement, as is written. And so because it is true, well, market is true. And again, it's not the false answer option that we're looking for so we can eliminate option C. So now we're between either option D or option E as this false answer option. And so when we take a look at options, he noticed that it says secondary active transport of glucose into cells is indirectly driven by a teepee. Hydraulics, ISS. And of course, we know from our last lesson video that secondary active transport is not directly linked to a teepee hydraulic sis. However, it is indirectly linked. And so what we're saying here is that option E Here is another true statement. And because it's true again, it's not the false answer option that we're looking for so we can eliminate Option E. And so, of course, this must mean that option D is the false answer option that we were looking for. And so it says that K plus and uh, in a plus potassium and sodium both the fuse into the cell along their concentration Grady INTs to drive the transport of glucose. But of course, we know that when it comes to the sodium potassium pump that potassium and sodium are gonna be pumped in opposite directions across the membrane. So they both will not be pumped into the cell. That would suggest that they're pumped in the same direction. And so option D here again is going to be the false answer option that we were looking for. And so what we can say is that, uh, this is the answer, and that concludes this practice. I'll see you guys in our next video.

Which of the following is a way in which primary and secondary active transport may work together?

• A. Primary active transport can be used to create a concentration gradient of sodium such that sodium and glucose can move into the cell together via antiport mechanism.
• B. Primary active transport is used to create ATP necessary to drive secondary active transport.
• C. Primary active transport can be used to create a concentration gradient of sodium such that sodium and glucose can move into the cell together via secondary active symport.
• D. Primary and secondary active transport always oppose each other so they never work together.