CONNECTIVE TISSUES

CONNECTIVE TISSUESStructure that is usually characterized by large amounts of extracellular materials that separate the cells from one another

Three types of protein fibers:

COLLAGEN FIBER

RETICULAR FIBERS

ELASTIC FIBERSConnective tissue cells are named according to their functions:BLAST (GERM) CELLS PRODUCE THE MATRIXCYTE (CELL) CELLS MAINTAIN ITCLAST (BREAK) CELLS BREAK IT DOWN FOR REMODELLINGEXAMPLES:

FIBROBLASTS

FUNCTIONS OF CONNECTIVE TISSUES:1. ENCLOSING AND SEPARATING sheets of connective tissues form capsules around organs such as liver and kidneys; connective tissues separate muscles, arteries, veins and nerves from one another2. CONNECTING TISSUES TO ONE ANOTHER tendonsAttaching muscles to bones, ligaments that hold bones together3. SUPPORTING AND MOVING -- bones of the skeletal system, cartilage support structures such as the nose, ears and surfaces of joints. 4. STORING. Adipose tissues (fat) stores high energy molecules; bones stores minerals such as calcium and phosphate5. CUSHIONING AND INSULATING. Adipose tissue cushions and protects the tissues it surrounds and provides insulation beneath the skin that conserves heat.6. TRANSPORTING. Blood transports substances through out the body.7. PROTECTING. Cells of the immune system and blood provide protection against toxins and tissue injury, as well as from microorganisms. Bones protect underlying structures from injury. CLASSIFICATION OF CONNECTIVE TISSUES:

1. LOOSE (AREOLAR) CONNECTIVE TISSUEELASTIC FIBERSCOLLAGENNUCLEUSLOCATION: SUBSTANCE ON WHICH EPITHELIAL BASEMENT MEMBRANE RESTS, PACKING BETWEEN GLANDS, MUSCLES, NERVES. ATTACHES SKIN TO UNDERLYING TISSUES.FUNCTION:LOOSE PACKING, SUPPORT AND NOURISHMENT FOR THE STRUCTURE WITH WHICH IT IS ASSOCIATED

2. ADIPOSE TISSUE

FAT CELLSNUCLEUSLOCATION: SUBCUTANEOUS AREAS, MESENTERIES, RENAL PELVES, AROUND KIDNEYS, ATTACHED IN SURFACE OF COLON, MAMMARY GLANDSFUNCTION:PACKING MATERIALTHERMAL INSULATORENERGY STORAGEPROTECTION OF ORGANS AGAINST INJURY FROM BEING BUMPED

3. DENSE CONNECTIVE TISSUE

A. DENSE COLLAGENOUS C.T.NUCLEUS OF FIBROBLASTCOLLAGEN FIBERSLOCATION: TENDONS AND LIGAMENTS; DERMIS OF THE SKIN, ORGAN CAPSULES, OUTER LAYER OF BLOOD VESSELS

B. DENSE ELASTIC C.T.LOCATION: ELASTIC LIGAMENTS BETWEEN THE VERTEBRAE, VOCAL CORDS, BLOOD VESSEL WALL4. CARTILAGE

CHONDROCYTESNUCLEUSMATRIXA. HYALINE CARTILAGELOCATION: GROWING LONG BONES, CARTILAGE RINGS OF THE RESPIRATORY SYSTEM, COSTAL CARTILAGE OF RIBS, EMBRYONIC SKELETONFUNCTION:ALLOWS GROWTH OF BONESPROVIDES RIGIDITY WITH SOME FLEXIBILITY IN THE TRACHEA, BRONCHI, RIBS AND NOSEFORMS THE EMBRYONIC SKELETON

CHONDROCYTE IN LACUNANUCLEUSCOLLAGEN FIBERSB. FIBROCARTILAGELOCATION: INTERVERTEBRAL DISKS, SYMPHYSIS PUBIS, BETWEEN KNEES, JAW JOINTSFUNCTION: SOMEWHAT FLEXIBLE AND CAPABLE OF WITHSTANDING CONSIDERABLE PRESSURECONNECTS STRUCTURES SUBJECTED TO GREAT PRESSURE

LOCATION: EXTERNAL EARS, EPIGLOTTIS AND AUDITORY TUBESFUNCTIONPROVIDES RIGIDITY WITH MORE FLEXIBLITY THAN HYALINE CARTILAGE, BECAUSE ELASTIC FIBERS RETURN TO THEIR ORIGINAL SHAPE AFTER BEING STRETCHED

5. BONE TISSUE

LACUNACENTRAL CANALMATRIX ORGANIZED INTO LAMELLAELOCATION: ALL BONES OF THE BODYFUNCTION:PROVIDES GREAT STRENGTH AND SUPPORTPROTECTS INTERNAL ORGANS SUCH AS THE BRAIN.PROVIDES ATTACHMENT SITES FOR MUSCLES & LIGAMENTSALLOW MOVEMENT

6. BLOOD

WHITE BLOOD CELLSRED BLOOD CELLSPLASMAFUNCTIONTRANSPORTS OXYGENCO2, HORMONES, NUTRIENTS, WASTE PRODUCTS, ETC.PROTECTS THE BODY FROM INFECTIONSINVOLVED IN TEMPERATURE REGULATION