So here we have an example problem that asks which of the following is an appropriate analogy for increasing resistance to blood flow in blood vessels. And we've got these four potential answer options down below. Notice that in each of these four potential answer options, the analogy used compares water flowing through a garden hose to blood flowing through blood vessels. Now, notice that the problem wants us to select the option that is an appropriate analogy for increasing resistance, and recall that resistance is any opposition to blood flow, or in other words, how difficult it is for blood to flow through the blood vessels. And so the greater the resistance is, the more difficult it is for blood to flow through. And so, really, we want to choose an answer option that is consistent with that.
Notice answer option A says, lubricating a garden hose so that water can flow through it faster. But if water is flowing through the garden hose faster, that's not making it more difficult for the water to flow through, it's making it less difficult since it's flowing faster. And so, for that reason, we can eliminate answer option A because that's consistent with decreasing resistance, not increasing resistance. Now answer option B says, cutting the end of a garden hose so that water has a shorter distance to travel. Now if water has a shorter distance to travel, that means less friction between the water and the garden hose, and less friction means that it's going to be less resistance. And so, that's not consistent with increasing resistance, so we can eliminate answer option B. Now answer option C suggests cutting a hole in the side of a garden hose so that some water leaks out as it flows through.
But again, this doesn't suggest that it will make it more difficult for the water to flow through the garden hose, and so for that reason, we can eliminate answer option C. And, of course, this leaves answer option D as the best answer, which says squeezing a garden hose, thereby slowing down the water flowing through it. Squeezing the garden hose is going to narrow down the diameter of the garden hose, and that's going to create more friction between the water and the garden hose. And so that is going to be consistent with, you know, slowing down the speed of the water going through it is consistent with making it more difficult for the water to flow through. So answer option D is an analogy consistent with increasing resistance to blood flow in blood vessels. So that here concludes this example, and I'll see you all in our next video.
