Connective and Nervous Tissues

connective tissue plays a major support role in the animal body. It connects, separates and cushions other tissues and is basically made up of some cells scattered within extra cellular matrix. Extra cellular matrix. Hopefully you remember is an array of proteins and this gel like substance called ground substance. And this functions as a support structure outside of eukaryotic cells in order to kind of play the role that a cell wall might, for example, that has a lot of other properties to. But you can think of it as a sort of surrogate cell wall. Give structural support Now. Loose connective tissue is the most common type of connective tissue found in vertebrates. It helps hold organs in place and attaches epithelial tissue, which is something we're going to talk about in just a moment now. Most notable type of loose connective tissue is at a post tissue or fat adipose. Tissue is mostly made up of these cells, called adipose sites, or that sells, and you can see an example of loose connective tissue. Here in these two images, these air both loose connective tissues. Now another type of connective tissue is dense, or sometimes it's called fibrous connective tissue, and this tissue is dense with collagen fibers. Uh, most notable are most notably, it's what makes up tendons, which connect muscle to bone, very important, and ligaments which connect bone to bone. Also very important. That's how your body moves. And you can see an example of this fibrous connective tissue right here above my head. Now, you also can have supportive connective tissue, and this is stuff like bone and cartilage, and these tissues provide structural integrity. You can see examples of bone and cartilage here. This is bone and right behind my head you have some cartilage these tissues form and a hard extra cellular matrix, which is what gives them that structural integrity. Lastly, there's fluid connective tissue, and this is basically blood. Blood cells have a liquid extra cellular matrix we call plasma. And here you can also just see a nice little example of how connective tissue functions with other tissues. The stuff stained in blue in this image is connective tissue, and this purple stuff that it is surrounding is a type of epithelial tissue. So you can see how the connective tissue here is supporting that epithelium now nervous tissue. Very important stuff, right? This is Well, this is how I'm thinking these thoughts and speaking to you right now, this tissue conducts electrical and chemical signals and is divided between the central and peripheral nervous systems, which we'll talk about when we discuss the nervous system in general. Now, the main type of cell that gets all the credit in the nervous system is nervous. Tissue, rather is our neurons thes receive and transmit the electrical signals. You can see a neuron here. This is a neuron. And it, uh it transmits these electrical signals by transporting ions across the membrane in what we call the action potential. We will talk about that again when we cover the nervous system. The main components of a neuron are the ax on, which is this portion here. That portion is the ax on, and he dendrites this branch stuff out here that I have circled. Those are the dendrites. Now the ax on you can kind of think of as the wire. This is the structure. It can be very, very long sometimes. And this is what transmits that electrical signal. The dendrites thes branch structures are what received signals and kind of figure out how the cell needs to respond to them now. The reason I kind of talked about neurons like they get all the attention, but they don't deserve it is because of these other cells in nervous tissue. Goliath Goliath do not get nearly enough credit. They're super super important. They, in fact, are support cells for neurons essential to their survival. Neurons would not live without these Goliath, and they also help the neurons with their functioning. And we'll get to the specifics of their roles when we talk about the nervous system. But let me just say that this beautiful Astra site that my head was covering this Goliath right here is probably responsible for much more of the functions of the nervous system than it actually gets credit for. A lot of current research and neuroscience is showing that glia playing much more important role than their initially given credit for, and they actually are also involved in signaling, albeit in a different way from neuron. So super important stuff don't write off glia. All right with that, let's turn the page