Copyright © 2010 Pearson Education, Inc. C h a p t e r 4 The Tissue Level of Organization PowerPoint® Lecture Slides prepared by Jason LaPres Lone Star College - North Harris Copyright © 2010 Pearson Education, Inc.
4-1 The four tissue types are epithelial, connective, muscle, and neural
Copyright © 2010 Pearson Education, Inc. Four Types of Tissues Tissues are groups of cells and cell products that perform specific, limited functions
Copyright © 2010 Pearson Education, Inc. Tissues of the Body Figure 4-1
Copyright © 2010 Pearson Education, Inc. 4-2 Epithelial tissue covers body surfaces, lines cavities and tubular structures, and serves essential functions
Copyright © 2010 Pearson Education, Inc. Epithelial Tissues Characteristics of Epithelia –Cellularity (cell junctions) –Polarity (apical and basal surfaces) –Attachment –Avascularity –Regeneration
Copyright © 2010 Pearson Education, Inc. Epithelial Tissues Functions of Epithelial Tissue –Provide physical protection –Control permeability –Provide sensation –Produce specialized secretions (glandular epithelium)
Copyright © 2010 Pearson Education, Inc. Intercellular Connections Support and Communication –CAMs (cell adhesion molecules): Transmembrane proteins –Intercellular cement: Proteoglycans –Hyaluronan (hyaluronic acid): Glycosaminoglycans
Copyright © 2010 Pearson Education, Inc. Intercellular Connections Cell junctions –Form bonds with other cells or extracellular material: Tight junctions Gap junctions Desmosomes (macula adherens) Intercellular Connections
Copyright © 2010 Pearson Education, Inc. Intercellular Connections Figure 4-2
Copyright © 2010 Pearson Education, Inc. Intercellular Connections Figure 4-2
Copyright © 2010 Pearson Education, Inc. Intercellular Connections Figure 4-2
Copyright © 2010 Pearson Education, Inc. Intercellular Connections Figure 4-2
Copyright © 2010 Pearson Education, Inc. The Surface of Epithelial Cells Figure 4-3
Copyright © 2010 Pearson Education, Inc. Epithelial Renewal and Repair Epithelia are replaced by division of germinative cells (stem cells) Near basal lamina
Copyright © 2010 Pearson Education, Inc. 4-3 Cell shape and number of layers determine the classification of epithelia
Copyright © 2010 Pearson Education, Inc. Classification of Epithelia Singular epithelium Plural epithelia Classes of Epithelia –Based on layers: Simple epithelium: single layer of cells Stratified epithelium: several layers of cells –Based on shape: Squamous epithelia: thin and flat Cuboidal epithelia: square shaped Columnar epithelia: tall, slender rectangles
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia Figure 4-4
Copyright © 2010 Pearson Education, Inc. Classification of Epithelia Figure 4-4
Copyright © 2010 Pearson Education, Inc. Classification of Epithelia Figure 4-4
Copyright © 2010 Pearson Education, Inc. Classification of Epithelia Figure 4-5
Copyright © 2010 Pearson Education, Inc. Classification of Epithelia Figure 4-5
Copyright © 2010 Pearson Education, Inc. Classification of Epithelia Figure 4-5
Copyright © 2010 Pearson Education, Inc. Glandular Epithelia Endocrine Glands –Release hormones: Into interstitial fluid No ducts Exocrine Glands –Produce secretions: Onto epithelial surfaces Through ducts Mechanisms of Glandular Secretion
Copyright © 2010 Pearson Education, Inc. Glandular Epithelia Mechanism of Secretion –Merocrine secretion: Is produced in Golgi apparatus Is released by vesicles (exocytosis) For example, sweat glands –Apocrine secretion: Is produced in Golgi apparatus Is released by shedding cytoplasm For example, mammary gland –Holocrine secretion: Is released by cells bursting, killing gland cells Gland cells replaced by stem cells For example, sebaceous gland
Copyright © 2010 Pearson Education, Inc. Mechanisms of Secretion Figure 4-6
Copyright © 2010 Pearson Education, Inc. Glandular Epithelia Types of Secretions –Serous glands: Watery secretions –Mucous glands: Secrete mucins –Mixed exocrine glands: Both serous and mucous
Copyright © 2010 Pearson Education, Inc.
4-4 Connective tissue provides a protective structural framework for other tissue types
Copyright © 2010 Pearson Education, Inc. Connective Tissues Characteristics of Connective Tissues –Specialized cells –Solid extracellular protein fibers –Fluid extracellular ground substance The extracellular components of connective tissues (fibers and ground substance) make up the matrix –Majority of tissue volume –Determines specialized function
Copyright © 2010 Pearson Education, Inc. Connective Tissues Functions of connective tissues –Support and protection –Transportation of materials –Storage of energy reserves –Defense of the body
Copyright © 2010 Pearson Education, Inc. Major Types of Connective Tissue Figure 4-7
Copyright © 2010 Pearson Education, Inc. Connective Tissues Cell Types of Connective Tissue Proper –Fibroblasts –Macrophages –Adipocytes –Mast cells
Copyright © 2010 Pearson Education, Inc. Connective Tissues Connective Tissue Fibers –Collagen fibers –Reticular fibers –Elastic fibers
Copyright © 2010 Pearson Education, Inc. Connective Tissues Ground Substance –Is clear, colorless, and viscous –Fills spaces between cells and slows pathogen movement
Copyright © 2010 Pearson Education, Inc. Types of Connective Tissue Proper Loose Connective Tissue –More ground substance, less fibers –For example, fat (adipose tissue) Dense Connective Tissue –More fibers, less ground substance –For example, tendons
Copyright © 2010 Pearson Education, Inc. Cells and Fibers of Connective Tissue Proper Figure 4-8
Copyright © 2010 Pearson Education, Inc. Connective Tissue Proper Figure 4-9
Copyright © 2010 Pearson Education, Inc. Connective Tissue Proper Figure 4-9
Copyright © 2010 Pearson Education, Inc. Connective Tissue Proper Figure 4–9
Copyright © 2010 Pearson Education, Inc. Connective Tissues Fluid Connective Tissues –Blood and lymph –Watery matrix of dissolved proteins –Carry specific cell types (formed elements) Formed elements of blood –red blood cells (erythrocytes) –white blood cells (leukocytes) –platelets
Copyright © 2010 Pearson Education, Inc. Supportive Connective Tissues Cartilage –Gel-type ground substance –For shock absorption and protection Bone –Calcified (made rigid by calcium salts, minerals) –For weight support
Copyright © 2010 Pearson Education, Inc. Supportive Connective Tissues Cartilage Matrix –Proteoglycans derived from chondroitin sulfates –Ground substance proteins Chondrocytes (cartilage cells) surrounded by lacunae (chambers)
Copyright © 2010 Pearson Education, Inc. Supportive Connective Tissues Cartilage Structure –No blood vessels: Chondrocytes produce antiangiogenesis factor –Perichondrium: Outer, fibrous layer (for strength) Inner, cellular layer (for growth and maintenance)
Copyright © 2010 Pearson Education, Inc. Supportive Connective Tissues Types of Cartilage –Hyaline cartilage: Stiff, flexible support Reduces friction between bones Found in synovial joints, rib tips, sternum, and trachea –Elastic cartilage: Supportive but bends easily Found in external ear and epiglottis –Fibrous cartilage (fibrocartilage): Limits movement Prevents bone-to-bone contact Pads knee joints Found between pubic bones and intervertebral discs
Copyright © 2010 Pearson Education, Inc. Types of Cartilage Figure 4-10
Copyright © 2010 Pearson Education, Inc. Types of Cartilage Figure 4-10
Copyright © 2010 Pearson Education, Inc. Types of Cartilage Figure 4-10
Copyright © 2010 Pearson Education, Inc. Supportive Connective Tissues Bone or osseous tissue –Strong (calcified: calcium salt deposits) –Resists shattering (flexible collagen fibers) Bone cells or osteocytes –Arranged around central canals within matrix –Small channels through matrix (canaliculi) access blood supply Periosteum –Covers bone surfaces –Fibrous layer –Cellular layer
Copyright © 2010 Pearson Education, Inc. Bone Figure 4-11
Copyright © 2010 Pearson Education, Inc.
4-5 Membranes are physical barriers of four types: mucous, serous, cutaneous, and synovial
Copyright © 2010 Pearson Education, Inc. Membranes –Are physical barriers –That line or cover portions of the body –Consist of: An epithelium Supported by connective tissues
Copyright © 2010 Pearson Education, Inc. Membranes Four Types of Membranes –Mucous membranes –Serous membranes –Cutaneous membrane –Synovial membranes
Copyright © 2010 Pearson Education, Inc. Membranes Mucous Membranes (Mucosae) –Line passageways that have external connections –In digestive, respiratory, urinary, and reproductive tracts –Epithelial surfaces must be moist: To reduce friction To facilitate absorption and excretion –Lamina propria: Is areolar tissue
Copyright © 2010 Pearson Education, Inc. Membranes Serous Membranes –Line cavities not open to the outside –Are thin but strong –Have fluid transudate to reduce friction –Have a parietal portion covering the cavity –Have a visceral portion (serosa) covering the organs
Copyright © 2010 Pearson Education, Inc. Membranes Three Serous Membranes –Pleura: Lines pleural cavities Covers lungs –Peritoneum: Lines peritoneal cavity Covers abdominal organs –Pericardium: Lines pericardial cavity Covers heart
Copyright © 2010 Pearson Education, Inc. Membranes Figure 4-12
Copyright © 2010 Pearson Education, Inc. Membranes Cutaneous Membrane –Is skin, surface of the body –Thick, waterproof, and dry Synovial Membranes –Line moving, articulating joint cavities –Produce synovial fluid (lubricant) –Protect the ends of bones –Lack a true epithelium
Copyright © 2010 Pearson Education, Inc. Membranes Figure 4-12
Copyright © 2010 Pearson Education, Inc. 4-6 The three types of muscle tissue are skeletal, cardiac, and smooth
Copyright © 2010 Pearson Education, Inc. Muscle Tissue Specialized for contraction Produces all body movement Three types of muscle tissue –Skeletal muscle: Large body muscles responsible for movement –Cardiac muscle: Found only in the heart –Smooth muscle: Found in walls of hollow, contracting organs (blood vessels; urinary bladder; respiratory, digestive, and reproductive tracts)
Copyright © 2010 Pearson Education, Inc. Muscle Tissue Figure 4-13
Copyright © 2010 Pearson Education, Inc. Muscle Tissue Figure 4-13
Copyright © 2010 Pearson Education, Inc. Muscle Tissue Figure 4-13
Copyright © 2010 Pearson Education, Inc. 4-7 Neural tissue responds to stimuli and conducts electrical impulses throughout the body
Copyright © 2010 Pearson Education, Inc. Neural Tissue Also called nervous or nerve tissue –Specialized for conducting electrical impulses –Rapidly senses internal or external environment –Processes information and controls responses
Copyright © 2010 Pearson Education, Inc. Neural Tissue Neural tissue is concentrated in the central nervous system –Brain –Spinal cord
Copyright © 2010 Pearson Education, Inc. Neural Tissue Two Kinds of Neural Cells –Neurons: Nerve cells Perform electrical communication –Neuroglia: Supporting cells Repair and supply nutrients to neurons
Copyright © 2010 Pearson Education, Inc. Neural Tissue Cell Parts of a Neuron –Cell body: Contains the nucleus and nucleolus –Dendrites: Short branches extending from the cell body Receive incoming signals –Axon (nerve fiber): Long, thin extension of the cell body Carries outgoing electrical signals to their destination
Copyright © 2010 Pearson Education, Inc. Neural Tissue Figure 4-14
Copyright © 2010 Pearson Education, Inc. 4-8 The response to tissue injury involves inflammation and regeneration
Copyright © 2010 Pearson Education, Inc. Tissue Injuries and Repair Tissues respond to injuries to maintain homeostasis –Cells restore homeostasis with two processes: Inflammation Regeneration
Copyright © 2010 Pearson Education, Inc. Tissue Injuries and Repair Inflammation = inflammatory response –The tissue’s first response to injury Signs and symptoms of the inflammatory response include –Swelling –Redness –Heat –Pain
Copyright © 2010 Pearson Education, Inc. Tissue Injuries and Repair Inflammatory Response –Can be triggered by: Trauma (physical injury) Infection (the presence of harmful pathogens)
Copyright © 2010 Pearson Education, Inc. 4-9 With advancing age, tissue repair declines and cancer rates increase
Copyright © 2010 Pearson Education, Inc. Aging and Tissue Structure Speed and efficiency of tissue repair decrease with age due to –Slower rate of energy consumption (metabolism) –Hormonal alterations –Reduced physical activity
Copyright © 2010 Pearson Education, Inc. Aging and Cancer Incidence Cancer rates increase with age –1 in 4 people in the United States develops cancer –Cancer is the #2 cause of death in the United States –Environmental chemicals and cigarette smoke cause cancer
Copyright © 2010 Pearson Education, Inc. Aging and Cancer Incidence Three most common types of skin cancer –Basal cell carcinoma –Squamous cell carcinoma –Malignant melanoma