BIO 425 Lecture Note: Chapter 5

Bio 425 (chapter 5) - The study of tissues 4 Primary tissue types: 1. Epithelial tissue (epithelium) cells derived from epithelium are part of linings, membranes, or glands. 2. Connective tissue ex. Blood, bone 3. Nervous tissue 4. Muscle Epithelial tissue characteristics - cells are tightly Packed together - Interstital fluid found between cells - Avascular (laeks a direct blood Supply - Always supported by connective tissue - Anchored by a layer of proteins known as the busemen membrane - Aprcal surface -The part of the cell furthest away from the basement membrane - Basal surface - The part of the cellclosest to the basement membrane - If there are multiple layers of cdls, thelayer closest to the basement membrane is the basal layer. The layer furthest from the basement membrane is the epical layer -Epithelial tissue is named based upon the apical layer. Amount of layers a simple epithelium - one layer of cells Ex. simple squamous epithelium Ex. simple columnar epithelium Ex simple cuboidal epithelium simple epithelium involved absorption, diffision, Altration, secretion b. stratified epithelium 12 or more layers)

Ex. stratified squamous protection C. Pseudostratified 1 layer of cells with a multilavered appearance (respiratory Hiset) Exception to this classification Scheme: Transitional epithelium (urothelium)-cell shapes vary based upon whether or not the tissue is stretched (found in bladder, ureters) Epithelial tissue may be ecitiated or keratinized (filled with keratin) Epithelial tissue may contain goblet cells( mucous) Lemen- Empty space exin the tube connective tissue 1. loose Connective tissue ( connective tissue proper) Gells arcloosely packed together 2. Dense Connective tissue (connective tissue Proper)-cells are more closely packed together than in loose CT 3. Cartilage(Supportive connective tissue) 4. Bone (supporter connective tissue 5. Blood (fluid connective tissue) What arewe concerned about in regards to connective tissue 1 The type & cells present The types of protein fibers(ifursible) (at times) Matrix ( in connective tissue The environment in the tissure where we find Cells and protein fibers. The matrix may be solid, liquid orgel (or Semigel)

we could also use the terms ground substance, ECF, or ECM Examples of cells: osteocyte f. mature bone cell chandrocyte = Cartilage cell Leukocyte= white blood cell Erythrocyte = red blood cell Adiopacyte = fatcell Macrophage = Phasocutic cell Fibroblast I cell that deposits/ secretes the matrix Examples of types of Protein fibers: Elastic fibers - made of the protein elastic yellow fibers' H collagen fibers - made of collagen thich white fibers u Reticular fibers- - Thin, delicate collagen fibers (found in the lumphatic system) Loose CT 1. Areolar tissue- - most common loose a wrap, cushion, and protat organs 2. Adpose tissue - contains adipocytes looks like marshmallows (hollow cells) nuclei appear to be on the outside of thecells like Ux wpo 3. Reticular tissue - contains reticular fibers, white blood cells Dense CT 1. Dense regular tissue Found in tendons and ligaments Paralbel arrangements of collagen fibers Fibroblasts 2. Dense irregular tissue - random arrangement of collagen fibers. Forms fibrous capsules (testes, kidneys) 3. Elastic tissue (some sources classify this as denter regular usuell)

6 Cartilage Large and surrounded by a space called laeunal plorais lacunae). The space chendrocyte - cartilage cell does not take up stain/ due. a. Heyaline cartilage - found at the ends of most bones/pracents friction 3 types of Cartilage: Matrix looks clear and contains chendroitin sulfate b. Fibrocartilage- contains collagen fibers. shock absor ption (knee, between? public bones, IVDs) C. Elastic cartilage- - contains elastic fibers. Helps maintain shape Couter ear, respiratory tract) Bonelosseous tissue) Osbone 1. Compact bone (cortical bone) -ussteon" arrangement I hoversian system. Matrix-hudro - X4 apatile (calcium phosphate and other mineral salts) spongy bone (cancellous bonel - bonecells are arranged on trabeculae (bony plates) Blood Matrix-plasma plasma proteins leukocytes Erythrocutes Platelets (cell Erayments) 0 Nervous tissue Neuron-the function unit of the nervous system(nerve cell) Scanned with CamScanner

Elial cell (neuroglial cell)-Supporting cell of the nervous system Muscle tissue a. Smooth muscle - found in the walls of organs. Involuntary and (non -streated) 3 types be skeletal muscle - Voluntary and striated (striped appearance due to the arrangement of postons). Moves the sheleton. Multinucleated C. Cardiac muscl- only found in theheart. Involuntary striated, branched fibers