Identify the type of transport described by each of the following:
a. An ion moves from low to high concentration in the cell.

Question

Identify the type of transport described by each of the following:

a. An ion moves from low to high concentration in the cell.

Accepted Answer

Alright. Hello everyone. So this question says that a certain type of cell requires potassium ions to be concentrated inside the cell at a higher level than in the extracellular fluid. Identify the type of transport responsible for maintaining this ion concentration in the cell. Option A says simple diffusion B says facilitated diffusion C says osmosis and option D says active transport. So before we talk about the specific scenario that we are given, let's just clarify the differences in the types of transport that are being listed here. Now, when it comes to some of these forms of transport, we have to distinguish between those that follow the concentration gradient and those that don't. Right. So what is the concentration gradient? Well, we call it by nature, substances tend to travel from areas of higher concentration towards area of lower concentration or areas of lower concentration. This is in an attempt to basically have an equal concentration of the substance in both areas or closer to an equal concentration. So this is the concentration gradient. Now when it comes to transport along the concentration gradient, then no energy input is required. In other words, no A TP is needed for the substance to move from high to low concentration. Now, by contrast, if we have something that we need to move from an area of low concentration to an area of high concentration that does require a TP because energy is needed for that substance to go against its normal gradient. And so that's actually what active transport is referring to now that I'm talking about that, right. So active transport is when you're forcing a substance to move from an area of low concentration to an area of high concentration with the use of a, with the use of energy. So that's active transport. The remaining anchos are going to deal with a substance moving from an area of high to low concentration. So the remaining three anchos don't require any, any energy osmosis. For example, option c refers to the movement of water specifically from high concentration or low solu concentration to an area of low water concentration or high salute concentration. So now let's talk about the difference between simple and facilitated diffusion because both simple and facilitated diffusion describe the movement of a substance that's not water from an area of high to low concentration. So what is the difference between them? Because neither method requires energy input. Well, it depends on the substance in question. So when it comes to deciding between whether or not a given substance is going to use simple or facilitated diffusion, the question you need to ask yourself is can the substance move across the cell membrane on its own? So if the answer to that question is yes. For example, if you have a small nonpolar molecule such as molecular oxygen or carbon dioxide, then that's simple diffusion because simple diffusion involves the movement of that substance across the cell membrane without assistance. Now, if the answer to that previous question was no, then that's facilitated diffusion. So this is going to involve for example, ions, right, ions and polar substances in general that cannot pass through the non polar cell membrane on its own. So facilitated diffusion requires some kind of carrier or channel for that substance to move across the cell membrane. All right. So now that we've addressed all of the answer choices and talked about the differences between them. Let's go back to the scenario at hand. So first and foremost, the substance in question is potassium ion. So osmosis won't be correct because osmosis refers to water specifically and we can also eliminate simple diffusion. Why? Because potassium being an ion cannot move through the cell membrane on its own. So, is it facilitated diffusion or active transport? Well, where is potassium starting? And where is it going to go? So let's go back to the statement. The statement says that the concentration of potassium inside of the cell has to be higher than the outside environment than the extracellular fluid. So potassium in this example, is moving from an area of lower concentration to an area of higher concentration inside of the cell. Therefore, right potassium ion is going against its concentration gradient, which requires the use of a TP. This means that option D is our correct answer because that's active transport and there you have it. So with all that being said, if you watch this video all the way through, thank you so very much. And I hope you found this helpful.

Identify the type of transport described by each of the following:
a. An ion moves from low to high concentration in the cell.

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Identify the type of transport described by each of the following:a. An ion moves from low to high concentration in the cell.

Verified video answer for a similar problem:

Key Concepts

Active Transport

Concentration Gradient

Ion Channels and Pumps

Identify the type of transport described by each of the following:
a. An ion moves from low to high concentration in the cell.