Compare the structure and functions of a lymph node to those of the spleen.

Video transcript

Hi, everyone. Let's look at our next problem. What is the primary difference between the functions of the lymph nodes and the spleen. A lymph nodes primarily filter blood while the spleen primarily filters lymph B, lymph nodes serve as a reservoir for red blood cells. While the spleen primarily filters pathogens. C lymph nodes activate and proliferate immune cells while the spleen initiates antibody production and D lymph nodes facilitate communication between immune cells while the spleen stores and releases platelets. Well, questions like this are a little bit tricky because it's saying what is the primary difference which tells us we're going to see other differences between these two. And we have to think about which one is the most important if we wanted to make a distinction. So the way I'd probably start is just by kind of listing briefly what I remember about each of those two organs and then using that to kind of filter through my answer choices. So unless it's really obvious right away, I'm not going to immediately go to, here's the biggest difference. Um And in this case, it is a little more subtle than that. So instead what I would do is sort of an answer. Generating strategy is just jot down sort of like in a brainstorming way. What I remember about each of these things and their characteristics. So I think about the fact that lymph nodes filter lymph, they filter that lymphatic fluid while the spleen actually filters blood. And when I think about the spleen filtering blood, uh it sort of works by it sort of monitors. Um I'm putting that in quotation mark, quotation marks, monitors four pathogens. So it's filtering the blood for the purpose of scanning for these pathogens. And then when it doesn't counter pathogen, it initiates an antibody response. So this is kind of the first response system. Now we think about the lymph system, the lymph nodes, excuse me, they're filtering that lymphatic fluid and then they also have a function of activating and proliferating immune cells. So sort of the sense of sustaining an immune response, sending those immune cells out there to do their job. And then finally, perhaps I should have started with this. But again, I'm emphasizing that when, if I were doing this on a test, it would be very uh kind of brainstorming stream of consciousness. And this didn't pop to my mind right away. Uh This lymph nodes are those small bean shaped organs and they're throughout the body. So found in different locations is locations throughout the body while the spleen is a larger organ. So a larger sort of singular organ whereas you have many lymph nodes throughout your body uh found in the abdomen. And if we think about it, although these are the location and size, a number of them are a very obvious difference. Just in terms of like gross anatomy, we know from having read through our answer choices that that wasn't one of them and that was focused more on uh the what they do, the roles they carry out. So I'm thinking about that just in my general thought processes. But that wasn't top of my mind. Given that I looked over the answer choices first. So let's go through them again. Remembering we're looking for a primary difference. So the first thing to rule out is obviously anything that's incorrect. And then we also might have a situation where we have correct descriptions that we wouldn't categorize as a primary difference. So in choice, A it says lymph nodes primarily filter blood while the spleen primarily filters lymph. Well, this is just wrong. These are actually reversed. So the lymph nodes filter lymph as we thought of right away and the spleen filters blood. So choice A is just incorrect. B says lymph nodes serve as a reservoir for red blood cells while the spleen primarily filters pathogens. Well, the spleen does filter pathogens, but the lymph nodes are not a reservoir for red blood cells. And I didn't think of this while generating the different things I could remember about each but one of the benefits of multiple choice questions is that brings that to my mind. Oh, the spleen is a reservoir for red blood cells. So that's one of its roles along with that important role of initiating an immune response. So, Choice B incorrect in its description of the lymph nodes, choy C says lymph nodes activate and proliferate immune cells while the spleen initiates antibody production. Well, this is correct and this is a really important distinction that spleen having that role of being that first responder initiating the antibody production and the lymph nodes causing that to chug along and progress activating and proliferating. This seems pretty clear as the biggest distinction between them, but we don't want to necessarily make that choice without evaluating choice. D So I'm gonna put a little dot rather than selecting it just because again, whenever you have that phrase, primary difference, uh that can be a little bit trickier. So then choice D lymph nodes facilitate communication between immune cells while the spleen stores and releases platelets. Here's an example of that tricky kind of answer choice. These are both correct descriptions of something. These organs do. Lymph nodes do facilitate communications between immune cells. The spleen does store and release platelets about 25% of the platelets in storage. But you wouldn't describe this as the primary difference between this them. So correct description of what they do. But if you were trying to really just make that uh strongest distinction between the two. Choice C is going to be a better answer than choice D. So we'll cross out choice D and go back and select choice C. So once again, that primary difference between the functions of lymph nodes and spleen choice C lymph nodes activate and proliferate immune cells while the spleen initiates antibody production. See you in the next video.