Tissues PDF

Tissues Tuesday, September 5, 2023 - 6:56 PM PART 1 PART 2...

Tissues Tuesday, September 5, 2023 - 6:56 PM PART 1 PART 2 PART 3 DEFINITION EPITHELIAL TISSUE: CLASSIFICATION CONNECTIVE TISSUE Tissues are a group of cells that are: → Can be classified by arrangements of layers → supports body structure → Similar in structure → Four types: → Perform a common or related function → Every cell is in contact → Multiple layers and not all 1. Connective tissue proper Histology : the study of tissues → Single with the basement cells are in contact with 2. Cartilage All come from the same cell when they are developing: → A subset of microscopic Anatomy → Have alignment of apical and basal membrane the basement membrane 3. Bone Mesenchyme cells → Useful for when substances need to → Only 1 layer → Better for protection, 4. Blood TYPES OF TISSUE pass through → Nuclei is spread out, not difficult to penetrate → Good for absorption an secretion in a general order → Functions: 1. Connective tissue → Can be found in the 1. Binding and supporting ○ Supports respiratory system 2. Protecting an immune protection ○ Connects → Can be classified by cell shape: 3. Insulating 2. Epithelial tissue 4. Storing reserve fuel ○ Protects ( ex: skin) 5. Transporting substances → There can have a combination of cell shapes 3. Muscle tissue ○ Like in the stratified arrangement ○ Moves CONNECIVE TISSUE STRUCTURE Movement 4. Nervous tissue ○ The fibers add structural integrity Controls ( ex: brain and nerves ) ○ Ground subs. + the 3 fibers = non-living component / EPITHELIAL TISSUE extracellular matrix Flat cubed long, skinny, tall ○ The rest are cells that make up the living component Two types: EPITHELIAL TISSUE Functions: 1. Covering / lining epithelium: forms outer layer of skin and internal structures 1. Protection 2. Glandular epithelium: forms glands of body → More layers - more protection 2. Absorption → Single layers means it's easier for substances to pass through 3. Secretion Lining epithelium → Cilia: often helpful in moving substances or involved in sensation 4. Sensory reception ○ Lines a structure ○ Found on apical surface ○ Forms on the outer layers of skin and outside the organs → Examples: → Stratified squamous: ○ Important for separating different compartments of the body ○ Very thick ○ Can also have a protecting factor ex: skin ○ Found in areas where protection is important § Ex: skin Granular epithelium: ○ Has cuboidal cells closer to the membrane ○ Forms a circular shape that normally produces a substance in the middle ○ The apical cells don't have a nucelli because they are dead § ex: salivary glands produce saliva”. § Bc they are dead and older they appear more dull which is why → Simple squamous you should moisturize → is the beige substance in the back Functions of epithelia: ○ Very thin → Can be water or gel-like 1. Protection ○ Located in areas where absorption/secretion is important CONNECTIVE TISSUE PROPER → Background fluid 2. Absorption § In blood vessels, air sacs in lungs 3. Secretion → Functions: 4. Sensory reception GLANDULAR EPITHELIUM ○ Binding ○ The hairs on the epithelia tissue can detect stuff which can send signals to the § Ex: epithelial tissue is binded to connective tissue beneath it brain to resolve the issue → GLANDS consist of one or more cells ○ Resists tension / mechanical stress → They make or secrete a particular substance § Ex: in the ligaments, which are made of connective issue proper and connect EPITHELIAL TISSUE: BASIC STRUCTURE one bone to another bone Two types: ○ Fat storage 1. Endocrine: substance is secreted directly into the bloodstream (usually hormones) ○ Provides reservoir for water and salts ○ Can go anywhere and effect any cells of the body only if the cell has a receptor for the secreted substance § Are needed for when we lose water/salt 2. Exocrine: substance travels through a duct / tube to its destination → 6 types (differ in density & fiber type): Apical Surface: free surface exposed to ○ A controlled process → Different types have different functions exterior environment or cavity of organ → Often have microvilli or cilia → Where is it found? ENDOCRINE ○ Adipose (fat) Basal Surface: anchored lower surface ○ Under (supporting) epithelia → Opposite to the apical ○ Ligaments (connect bones) The thyroid gland → Produces hormones the body needs Basement membrane / basal Lamina: CARTILAGE adhesive (sticky) sheet beneath Basal Picture description: Surface; joins epithelial tissue to → Functions: connective tissue ○ Resists compression (high level of water in matrix) ○ A single thyroid gland will be surrounded by epithelial tissue and will → Acts as a filter, it can decide what ○ Cushions and supports body structure make whatever is needed and the product will stay stored in the middle things can cross over in either ○ Can be found at the end of bones to prevent from rubbing against ○ When it's ready / developed it will get diffused through the epithelial direction each other which is rlly bad cells and into the blood vessels → 3 types: ○ There are blood vessels close by bc they are waiting for the substance 1. Hyaline ◊ Most common EPITHELIAL TISSUE: FUN FACTS 2. Elastic EXOCRINE ◊ Can stretch / mobile → fit closely together to form continuous sheets → sit upon and are supported by connective tissue ◊ Found in the nose and ear → avascular (does not get blood supply from arteries or veins) but innervated ( gets a 3. Fibrocartilage The exocrine gland - sweat glands nerve supply that connects to the brain or spine) ◊ Tough but more mobility than hyaline → High regenerative capacity ◊ Found between the joints of the pelvis -> aid in birth giving Picture description: ○ Means damaged epithelial tissue can regenerate quickly § It can do this with no blood bc it gets its nutrients and oxygen from near by BONE ○ Lumen: open area in the middle of the gland blood vessels ○ A duct will run from the lumen to the skin and be released as → Functions: sweat ○ Very hard; resists compression and tension ○ Supports Additional notes: → Two types: ○ Another gland is the salivary glands that secrete saliva in / 1. Contact around the mouth 2. Spongy ◊ More space between it ◊ Marrow can be found in the space → Bones get strength from collagen and calcium BLOOD → Functions: ○ Fluid tissue ○ Carries Oxygen (O2), carbon dioxide (CO2), nutrients, wastes, other substances (hormones) MUSCLE → High cell concentration ○ Lots of cells packed close together → Highly vascularized ○ Gets a high amount of blood supply → Responsible for most body movements NERVOUS TISSUE → Main component of Nervous System: Brain, Spina Cord, Nerves → Two cell types: 1. Neurons -> electrical signalling cells 2. Supporting cells -> helper cells that don't pass electronical signals