Potassium, magnesium, and phosphate ions are the predominant electrolytes in a. plasma, b. interstitial fluid, c. intracellular fluid.

Video transcript

Hi everybody. Our next question asks, what are the predominant ions present in the intracellular fluid? A potassium magnesium and phosphate. B, sodium chloride and bicarbonate. C zinc, iron and copper or D iodine bromine and chlorine. So we have sort of two parts here. We're talking about predominant ions. So the ions that are present in the greatest amount and we're talking about the intracellular fluid. So we need to remember this is the fluid inside the cells. So when we look at our answer choices, we've got two that we can eliminate right away. Uh Choice C zinc, iron and copper. These are trace elements. So found in very, very tiny amounts in the body and they're found generally bound to proteins or in special cellular compartments, but not just floating around and certainly not the predominant ions. So that's why choice C we can eliminate right away. Android D iodine, bromine and chlorine. Uh again, these ions are present can be in the body but definitely not the predominant, not present in nearly as much amount as some of the more common ions. So we can sort of take those out of the picture right away. So now, we have some ions that really are present in rather large amounts, potassium magnesium and phosphate and then sodium chloride and bicarbonate. So now we need to turn to the intracellular fluid and that's going to bring us to choice. A potassium magnesium and phosphate are all found inside the cell. They all have important roles there. Potassium is involved in maintaining cellular potential. We know that the calcium ions leaving the cell helps to reset the membrane potential. After an action potential has happened. Magnesium is important in enzymatic activities in the cell and phosphate involved in energy storage and transfer, breaking those phosphate bonds or adding a phosphate on helps to either store energy or release energy choice. B sodium chloride and bicarbonate again, very important ions. But they're found in general in the extracellular fluid, not the intracellular fluid. So that's why not they're not the correct answer. So once again, the predominant ions present in intracellular fluid choice. A potassium magnesium and phosphate. See you in the next video.