Biol 32 Tissue Lecture Notes

a "fabric" or group of cells with similar structure and function

• Epithelium (covering)
• Connective (support)
• Muscle (movement)
• Nervous (control)

• Histology
• Biopsy
• Autosy

sheet of cells that cover all free body surfaces (inside and out), forming an interface between two environments 

• Protection: often in areas that get scraped off
• Absorption: intake of molecules and substances
• Filtration: closely fitted cells can form a "strainer" with small holes
• Secretion: release of molecules and substances
• Senory reception

• Macrovilli
• Cilia

• increase in surface area and used for absortion
• fingerlike extentions of epithelial cells lining some parts of the digestive tract or kidney. may also create adhesion points for secreted mucus

microtubules project from cell membranes as hair that moves uniformly in one direction (wave like). They can move substances along the surface of a sheet of epithelial cells. (nicotine decreases ciliary action)

• Demosomes: linking protiens between cells
• Tight Junctions: fuse adjacent plasma membranes together into leak proof sheets, seals extracellular space
• Gap Junctions: allows substances to leak between cells <--->

• Basal Lamina
• Basement membranes

• 1) noncellular, adhesive sheet of glycoproteins secreted by epithelial cells toward the nighboring connective tissue layer.
• 2) Functions: Selective filter, Scaffold to which epithelial cells can migrate or grow upon
• 3) combines with fiber from CT layers to form basment membrain

• 1) located just deep to basel lamina
• 2) reinforces epithelial sheet and defines epithelial boundary

• Simple: one layer
• Stratified: more than one layer
• Psedostratified: looks like more than one layer but isnt

• Squamous: flat, plate-like (nucleus: flat & disk-like)
• Cuboidal: cube-shaped (nucleus: large & round)
• Columnar: column-like (nucleus: oval, located in basal 1/3)

• 1) Glands: one or more epithelial cells organized to secrete a particual product (protien) - but not always
• 2) Secretory pathway: RER --> Golgi --> vesicles --> exocytosis
• 3) Two major gland types: endocrine and exocrine

• Ductless (secretion into the blood stream) 
• each messenger (hormone) is manufactured to react with specific "target" organs and or cells. (ex: pancreas)

• 1) Secrete products to a body surface (ex: skin surface, body cavities. or passages leading outside)
• 2) Unicellular (ex: single goblet cell secretes a protien called mucin) 
• 3) Multicellular: secretory unit + duct (ex: sweat and oil glands)

• connective tissue proper
• cartilage
• osseous tissue (bone)
• blood

• binding (connection) and support
• protection (bones, blood)
• insulation (fat)
• transportation (blood)

• 1) Fibrocyte
• 2) Chondrocyte
• 3) Osteocyte

• Ground Substances : holds water and ranges from liquid to jello firm; and is composed of:
• Water 
• Adhesion Protiens ex- demosomes
• Polysaccaride molecules. 
• Fibers : (fiberblasts) produced by cells and has 3 different types which consist of: 
• Collegen fibers (strength) 
• Elastic fibers (recoil) 
• Reticular fibers (fine collagen, but more give)

• skeletal muscle
• cardiac muscle
• smooth muscle

• Neuroglia (nerve support cells)
• Nuurons (nerve cells)

• Irritability (consents and responds)
• Conductivity (sends impulses to other areas of the body)

• Dendrites (tend to be small and receive the signals, can have or be multiples)
• Cell body
• Axon - 1 per neron/cell or 1 message to be as specific as possible
• Axonal (presynaptic) terminals - which is the end point of an axon and sends the message

• External defenses (outside)
• Internal defenses (inside)

• Mechanical
• Chemical
• Microbiological

• Inflammatory response - non specific and develops quickly (chemicals and some white blood cells)
• Immune response - specific and takes longer (like antibiotics, some white blood cells)

• Regeneration
• Fibrosis

is the replacement of destroyed tissue with same kind of tissue (ex - epithelium with epithelium)

replacement of destroyed tissue with fibrous connective tissue (called scar tissue)

• Inflammation
• Organization
• Regeneration and fibrosis

epithelial tissue, bone, areolar, and blood forming tissue regenerate extremely well

smooth muscles and dense regular connective tissue have a moderate capacity for regeneration

skeletal muscle and cartilage have a weak regeneration capacity

Cardiac muscle and nervous tissue in the brain and spinal cord have virtually no functional regeneration capacity and are routinely replaced by scare tissue

• Cutaneous membranes (skin)
• Mucous membranes "mucosa" covers all portals to the inside and produces mucus
• Serous membranes "serosa" line closed internal cavities and cover outside of organs, and produces serous fluid "lubrication"

Synovial membrane - lines the inside of freely movable joints and produces synovial fluid "lubricant"