BIO 230 Chapter 3 Connective Tissues

Supportive connective tissue BONE

- made of osteons Osteons consist of ~central canal ~osteocytes ~Lacunae ~Canaliculi ~Matrix of Lamellae

Connective Tissue Proper -Loose -Areolar

-"Packing materials" of the body -more ground substance, fewer fibers LOCATION -deep dermis -everywhere FUNCTION -fill spaces between organs, provides cushioning -support epithelia -anchor blood vessels and nerves -stores lipids

Fibrocytes

-active fibroblasts -differentiate from fibroblasts -have the ablity to turn back into fibroblasts -second most aboundent fixed cell

Classification of Connective Tissue

-connective tissue proper -fluid connective tissue -supporting connective tissue

Adipocytes

-contain a single lipid droplet -aka fat or adipose cells

Fluid Connective Tissue Blood

-distinct cell types in a fluid matrix with dissolved proteins -plasma~watery matrix ~red blood cells ~white blood celss ~proteins ~platelets

Fixed Macrophages (connective tissue proper)

-engulf damaged cells, dead cells and pathogens -upon stimulation release chemicals that attract wandering cells -aka resident or resting macrophages

Functions of Connective Tissue

-establish structural framework for the body -transport fluid and dissolved materials -protect delicate organs -support, surround and interconnect with other tissue types -store energy; usually lipids -defend the body from invasion by microorganisms

Connective Tissue Proper Wandering Cells

-free macrophages -mast cells -lymphocytes -neutrophils -eosinophils

Reside in Mast Cells

-histamine and heparin -these chemicals are released after injury or infection and stimulate local inflammation

Free Macrophages (wandering cells)

-large phagocytic cells atht wander rapidly through the connective tissues -aka wandering macrophages or elicited macrophages

Fibroblasts

-manufactures and secretes protien subunits -secrete hyaluronan (makes ground substane viscous) -most abundent fixed cell -the only cell that is always present

Connective Tissue Proper Fixed Cells

-mesenchymal (stem) cells -fibroblasts -fibrocytes -fixed macrophages -adipocytes -melanoctyes

Lymphocytes

-migrate throughout the body -mulitple whenever tissue damage occurs -may develope into plasma cells

Connective Tissue Proper Dense Irregular

-more fibers(mostly collagen); less ground substance -resist distortion -resists tension from many directions LOCATION -deep dermis of skin -capsules of visceral organs

Neutrophils and Eosinophils

-phagocytic blood cells that are smaller then monocytes -small number migrate through connective tissue -attracted to an area when stimulated by macrophages and mast cells chemical release

Plasma Cells

-produce antibodies

Mast Cells

-small, mobile connective tissue cells often found near blood vessels

Components of Connective Tissue

-specialized cells -extracellular protein fibers -ground substance

Melanocytes

-synthesize and store the brown pigment melanin

Connective Tissue Fluid Lymph

-white blood cells -dissolved proteins -lymph fluid

Appositional Growth

1) Cells in cellular layer of perichondrium differentiate into condroblasts 2)Immature chloroplasts secrete new matrix 3) As Matrix englarges, more chondroblasts are incorporated. Cells are replaced by stem cells in perichondrium

Interstitial Growth

1)Chondocyte undergoes division within a lacuna surrounded by cartilage matrix 2) Daughter cells secrete additional matrix as they move apart expanding cartilage from within

Supporting Connective Tissue

CARTILAGE -Gel matrix made of chondroitin sulfate -cells reside in lacunae BONE -solid matrix made of calcium phosphate -Cells reside in lacunae

Elastic Cartilage Tissue

LOCATION -Auricle of ear -Epiglottis -Auditory Tube FUNCTION flexible support MATRIX gel

Hyaline Cartilage Tissue

LOCATION -between ribs and sternum -within joints of elbows and knee -Tracheal cartilage rings FUNCTION -flexible support -reduces friction MATRIX gel

Connective Tissue Proper- Loose- Adipose

LOCATION -deep to skin -buttocks -breasts FUNCTIONS -provides padding cushions and shock -insulates -stores energy

Fibrous Cartilage Tissue

LOCATION -pads within knee joins -pads between spinal vertebrae -Pubic symphysis FUNCTION -resists compression -absorbs shock MATRIX gel

Matrix

Mix of extracellular fibers and ground substance that surrounds cells in connective tissues

Antibodies

Specialized proteins that aid in destroying disease

Connective Tissue Proper Dense- Regular

Tough, Strong, and durable -more fibers(mostly collagen); less ground surface -resist tension -interconnect bones tendons skeletal muscle to bone ligaments bone to bone

Monocytes

free macrophages in the blood

Wandering Cells

help defend and repair damaged tissues

Mesenchymal cells

stem cells that respond to local injury or infection