Connective Tissue Most common tissue found in body Can be delicate-thin, tough-rigid or fluid Main Functions Connect Muscle to muscle muscle to bone Bone to bone Supports Framework for body and organs Transports blood Defends Protects against microorganisms

Connective Tissue Characteristics Matrix-intercellular material, fibers Ground substance, provides medium for exchange of substances components of matrix and ground tissue define the type of tissue Highly vascular and innervated (not all) Mesenchyme- tissue in embryo that all other connective tissue arises from

Types of Fibers Fibroblasts create these protein fibers Collagen (white fibers) most common protein in body Tough and strong Occur in bundles Hydrated form known as gelatin Reticular Special type of collagen, reticulin Occur in bundles yet are delicate Supports capillaries and nerve fibers Elastic fibers Retains shape after being stretched Made from protein elastin Found in stretchy tissue such as the external ear Proteoglycans Made of polysaccharide chains containing glucosamine Thicken the matrix to create barrier against bacteria/microbes Transparent lubricant that hold tissue together

Classification of Connective Tissue Fibrous (loose) Areolar (ordinary) Adipose Reticular Dense Bone Cartilage Hyaline Fibrocartilage Elastic Blood

Areolar(loose ordinary) Elastic glue that permits movement Stretchable and very common Matrix is soft thick gel, contains hyaluronidase Hyaluronidase is an enzyme that can change thick gel matrix to watery state Contain interwoven fibers of collagen and elastin Main types of cells Fibroblasts- synthesizes ground substance and fibers Macrophages(histiocytes)- carry on phagocytosis Mast cells- wandering white blood cell Fat & plasma cells

Areolar(loose ordinary)

Adipose Tissue Mainly fat cells Few fibroblasts, mast cells and macrophages Cushions organs Stores excess energy Conserves body heat

Adipose Tissue

Reticular Tissue 3 dimentional meshwork of reticular fibers Defense against microorganims and injurious substances Filters toxic substance out of blood and lymph Framework for spleen, lymph nodes and bone marrow

Reticular Tissue

Dense Fibrous Tissue Fibers are densely packed in matrix Bundles of collagen fibers Flexible but very strong Regular is parallel fibers Tendons(muscle to bone) Ligaments, more elastin (bone to bone) Irregular (wavy) dense tissue withstands stress from any direction Forms dermis Outer capsule of kidneys & spleen Dense Fibrous Irregular

Dense Fibrous Tissue Dense Fibrous Regular

Bone (osseous tissue) Characteristics Osteocytes- mature bone cells Matrix contains mineral salts and collagen Mineral salts are responsible for hardness of bone Ostecytes are trapped in small spaces called lacunae Haversian canals allow blood vessels to bring nutrition to cells Functions Protection Movement Mineral storage Create blood cells

Bone Tissue

Cancellous Bone (spongy bone) Ossified Bone (hard bone)

Cartilage Tissue Characteritics Chondrocyte- only type of cell in cartilage Chondrocyte produce tough fibers and ground substance *Chondrocyte found in lacunae Avascular and no nerves Substances must diffuse through connective tissue surrounding cartilage called perichondrium

Types of Cartilage Hyaline(greek for glass) Low amounts of collagen Shiny translucent appearance Found in respiratory rings end of bones

Hyaline Cartilage

Types of Cartilage Fibrocartilage Strongest type of cartilage Densely packed with white collagen Shock absorbers Intevertebral discs and knee joints

Intervertebral Disc

Fibrocartilage 400X Dense Fibrous Connective 100X

Types of Cartilage Elastic Cartilage Very little collagen Many very fine elastin fibers Highly flexible External ear, voice box, layrnx “Hairier” that hyaline

Elastic Cartilage

Blood Tissue Has neither ground substance nor fibers Exists in liquid state, plasma Erythrocytes- red blood cells Leukocytes- white blood cells Thrombocytes- platelets Moves gases, nutrients & wastes Hematopoietic tissue- blood forming tissue

Blood Tissue

Muscle Tissue High degree of contractility Provide movement and produce heat Skeletal (striated voluntary) Smooth (non striated involuntary or visceral) Cardiac (striated involuntary)

Skeletal Muscle

Skeletal Muscle

Smooth Muscle

Smooth Muscle

Smooth Muscle

Cardiac Muscle

Cardiac Muscle

Nerve Tissue Functions Structures Regulates and integrates body functions High conductivity and excitability Structures Neurons Neuroglia (supporting cells) Brain, spinal cord, nerves

Nerve Tissue

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