in this video we're going to provide a brief overview of four primary tissue types um so before we do that um just as a reminder a tissue is a collection of cells that are similar in structure and function and these cells come together to perform the similar function in form of tissues the science that studies tissues is known as histology and we are going to have um some separate videos where we talk about each of these tissues in more details but um in this video which is going to provide some basic characteristics for all four of them so i'm going to start with epithelial tissue and epithelial tissues um have as primary function to form coverings or create linings so if we think about examples such as the skin or linings in internal organs like the lining of a digestive system of a lining of a urinary system that's where um peptophilia tissue is best in addition to that we have what's known as glandular epithelium so um epithelial tissues form glands and we know that particles glands are endocrine glands and this endocrine glands can form hormones and these hormones part of the endocrine system regulate control a lot of functions within the body so actually the endocrine system uh just like the nervous system controls and regulates pretty much everything that happens in the human body epithelial tissues are highly cellular what that means is that we have lots and lots of cells that are densely packed and not a lot of matrix so little matrix in addition to that um some of the primary functions that the epithelial tissue is performing in the human body is to absorb and succeed and we are going to talk a little bit more about what this means when we talk about epithelial tissues finally certain junctions that are found within epithelial tissues we're going to talk about tight junctions later but they are crucial crucial in making sure that this epithelial tissues can create those linings or coverings cause barriers um in a lot of places in the board okay the second type of primary tissue type is connective tissue connective tissue is mostly there for support and protection unlike all varva primary tissue types connective tissue has lots of matrix and less cells what's interesting about the connective tissue is that it's very varied so it's buried um and if we think about a couple of examples bones um are formed mostly of connective tissue right so think bones at the same time blood is also an example of connective tissue right so we can see much difference between subtypes of connective tissue it's also most widely distributed so think about connective tissue diseases they become challenging particularly because of this wide distribution of connective tissue the third type of primary tissue type is muscular and when we think about muscular tissue obviously primary function is movement but there are three types of muscle tissue so we have skeletal we have cardiac and we have smooth so uh literally with muscular tissue there is different types of movement right so skeletal muscle helps us move from point a to point b or helps us move different parts of the body like my arms my legs cardigan muscle helps us move blood for blood vessels smooth muscle helps us move different contents of organs like urine or food through the digestive system so uh although the overall overarching function is movement is just sort of different types of what we move right uh one specific characteristic of muscular tissues but this is the tissue but contracts and exerts force no other tissue is going to do it this is very unique to all types of muscle tissue muscular tissue is highly cellular so very much like um epithelial tissue the nervous tissue we see lots of cells that are densely packed and that means that it has little matrix there are certain electrical events that are happening in muscle tissue but will allow that muscle to contract um it can also stretch and then come back to its original length we're going to talk more about this when we discuss muscle tissue in more details the last one is nervous tissue a nervous tissue um the overall function is control and regulation so again together with the endocrine system the nervous tissue controls every function in the body all the very different components that are formed by nervous eye tissue we primarily discuss the brain and the spinal cord right now remember we talked about cranial cavity and we talked about the vertebral canal so nervous tissue is very very delicate um it needs lots of oxygen to survive and this bony structure is around nervous tissue provides us with best protection so nervous tissue is also highly cellular uh does it have lots of matrix or less a little matrix i and you're noticing that three out of the four primary tissue types are highly cellular and do not have a lot of matrix where the connective tissue is very very different so uh this is the tissue level again for primary tissue types as we talk more about epithelial connective and muscle tissue we're going to discuss the subtypes of wave locations and specific functions for both subtypes