We're about to spend some time learning the organ systems of the body. Now just quickly remember an organ system is a group of organs that coordinate to perform a common function. Now we're learning them now because the study of anatomy and physiology, this course the course that you're taking it's often broken up by these systems. If you look at the chapters in your textbooks, the units of their course, it's usually different organ systems or groups of organ systems. Here, as we go through them, we're going to group them by function, and the groups that we do here are pretty common and quite often the order that you'll go through them in your course.
First off, we're going to have protection, structure, and support. That's going to be the integumentary system, your skin, the skeletal system, and the muscular system. Then we'll talk about communication and integration, your nervous system, and your endocrine systems. We'll talk about transport and immunity, the circulatory or cardiovascular system, and the lymphatic system. And as part of the lymphatic system, we'll talk about the immune system. Next, we'll do nutrient gas and waste exchange. That's going to be your digestive system, your respiratory system, and your urinary system, sometimes called the excretory system. And lastly, we'll talk about reproduction. That's going to be the reproductive system. And each person has one of those systems, but obviously there are 2 main variants, the male and female reproductive systems.
Now it's important to remember that bodies are highly integrated. No organ system does its job completely on its own, and organ systems also have many overlapping functions. So as we go through each system, we're going to list 1 or 2 or 3 of their main functions. Almost certainly, these systems do other things. We're just trying to hit the big ones right now. And as we list those functions, remember almost certainly it doesn't do it on its own. It can be really hard in the body to draw distinct lines that this does that and this does that. But we still try to group things because we're humans and that's what we like to do.
All right. Last thing to know: As we go through these different organ systems, we'll be talking about the different organs that belong to each one. You are not expected to know all the organs of the body at this point in the course, but you probably know a lot of organs already. So the ones that you do know, you should start organizing in your head by body systems. With that, let's learn some body systems.