TISSUES III. CHARACTERISTICS OF CONNECTIVE TISSUES: binds/supports/ protects other tissues and organs, derived from mesenchyme (embryonic CT)A. Consists of:1. Cells: the cells don’t have a free surface.2. Matrix = the non-living material surrounding the cells. It containsa. Fibers (protein)i. Collagenii. Elastiniii. Reticularb. Ground Substance3. Vascularity variesII. CLASSIFICATION OF C.T.A. Connective Tissue Proper: Matrix is gel-like; Two classes: Loose C.T. & Dense C.T.1. Loose CTa. Areolar CTi. Contains fibroblasts, many irregularly arranged fibers and it is very vascularii. Location: surrounds nerves, muscles, and some organsiii. Function: packing & binding materialb. Adipose (Fat Tissue)i. Contains adipocytesii. Location: primarily in skiniii. Functions: energy source; insulation against temperature changes, and protection2. Dense CTa. Dense Irregular CTi. Contains fibroblasts; protein fibers found are irregularly arranged bundlesii. Location: skiniii. Function: strength and support (in all directions) b. Dense Regular CTi. Contains fibroblasts; protein fibers are arranged in parallel bundles. Poor vascularityii. Location: skiniii. Function: Strength and support (in one direction)B. Cartilage: semisolid matrix; avascular; flexible; heals slowly; cells = chondroblasts and chondrocytes; cells in lacunae.1. Hyaline (clear) Cartilage:a. Matrix contains very fine collagen fibers.b. Location: found on articular surfaces, nasal septum, trachea, fetal skeleton (ends of bones) c. Function: support and protection.2. Fibrocartilagea. Matrix contains thick collagen fibers.b. Location: found in intervertebral disks, symphysis pubis & meniscic. Function: support & withstands compression3. Elastic Cartilagea. Matrix contains numerous elastic fibersb. Location: outer ear and larynx (voice box)c. Function: flexibility and strengthC. Bone (Osseous Connective Tissue): matrix is rigid1. 3 kinds of cells found in bone:a. osteoblasts – immature bone cells (create bone)b. osteocytes – mature bone cells – maintain bonec. osteoclasts – break down/absorb bone2. Two kinds of bone tissue found within each of your bones:a. Compact (dense): outer shell of bone.b. Spongy (cancellous): inner lattice-work of bone; hemopoietic (red bone marrow) tissue found within spacesD. Vascular Tissue (Blood) 1. Contains blood cells (or formed elements) and a liquid matrix called plasma2. Function: transportIII. MUSCLE TISSUE: moves body and materials within bodyA. Classification1. Smooth (Visceral) Muscle Tissue (involuntary)a. Spindle-shaped cellsb. One centrally located nucleus (find it in the walls of holloworgans besides the heart)2. Cardiac Muscle Tissuea. Short, cylindrical cellsb. Some cells are bifurcated (branching) c. Has one or TWO centrally- located nucleid. Intercalated discse. Striations3. Skeletal Muscle Tissuea. Long, cylindrical cellsb. Multinucleatedc. Nuclei located at periphery of celld. StriationsIV. NERVOUS TISSUE: makes up the nervous systemA. Classification1. Neuronsa. Generate and conduct nerve impulses2. Supporting Cells (Neuroglia)b. Support, protect and nourish neuronsWhich of the following is found in the outer ear and larynx and functions to provide flexibility and strength?a. Dense regular connective tissueb. Areolar connective tissuec. Fibrocartilaged. Elastic cartilagee. Dense irregular connective