Chapter 5 Lecture PowerPoint Tissues Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

5.1: Introduction There are four (4) primary or major tissue types: Similar cells with a common function are called tissues. The study of tissues is called histology. There are four (4) primary or major tissue types: Epithelial Tissue Connective Tissue Muscle Tissue Nervous Tissue

Intercellular Junctions Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Tight junctions Close the space between cells Located among cells that form linings Cell membrane Tight junction Desmosomes Form “spot welds” between cells Located among outer skin cells Cell membrane Desmosome Cell membrane Gap junctions Tubular channels between cells Links cytoplasm of 2 cells Located in cardiac muscle cells Gap junction

5.2: Epithelial Tissue General characteristics: Cover organs and the body Line body cavities Line hollow organs Have a free surface (apical) Have a basement membrane Are avascular Cells readily divide Cells tightly packed Cells often have desmosomes Function in protection, secretion, absorption, and excretion Classified according to cell shape and number of cell layers

Epithelial Tissue Simple squamous: Simple cuboidal: Single layer of flat cells Substances pass easily through Line air sacs Line blood vessels Line lymphatic vessels Simple cuboidal: Single layer of cube-shaped cells Line kidney tubules Cover ovaries Line ducts of some glands Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Free surface of tissue Lumen Simple squamous epithelium Nucleus Basement membrane Basement Free surface of tissue Nucleus Simple cuboidal epithelium Connective tissue Connective tissue (a) (b) (a) (b) b,d: © Ed Reschke b: © The McGraw-Hill Companies, Inc./Al Telser, photographer

b: © The McGraw-Hill Companies, Inc./Al Telser, photographer. Epithelial Tissue Simple columnar: Single layer of elongated cells Nuclei usually near the basement membrane at same level Sometimes possess cilia Sometimes possess microvilli Often have goblet cells (secrete mucus) Line uterus, stomach, intestines Pseudostratified columnar: Single layer of elongated cells Nuclei at two or more levels Appear striated Often have cilia Often have goblet cells Line respiratory passageways Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cilia (free surface of tissue) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cytoplasm Mucus Nucleus Goblet cell Cytoplasm Nucleus Microvilli (free surface of tissue) Basement membrane Connective tissue Goblet cell (a) (b) Basement membrane b: © The McGraw-Hill Companies, Inc./Dennis Strete, photographer Connective tissue (a) (b) b: © The McGraw-Hill Companies, Inc./Al Telser, photographer.

Epithelial Tissue Stratified squamous: Stratified cuboidal: Many cell layers Top cells are flat Outer layer of skin Line oral cavity, vagina, and anal canal Stratified cuboidal: 2-3 layers Cube-shaped cells Line ducts of mammary glands, sweat glands, salivary glands, and the pancreas Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Free surface of tissue Stratified cuboidal epithelium cells Squamous Nucleus Lumen Free surface of tissue Basement membrane Connective tissue (a) (b) Layer of cells dividing Basement membrane b: © The McGraw-Hill Companies, Inc./Al Telser, photographer. Connective tissue (a) (b) b: © The McGraw-Hill Companies, Inc./Al Telser, photographer

b: © The McGraw-Hill Companies, Inc./Al Telser, photographer Epithelial Tissue Transitional: Many cell layers Cube-shaped and elongated cells Line urinary bladder, ureters, and part of urethra Stratified columnar: Top layer of elongated cells Cube-shaped cells in deeper layers Line part of male urethra and part of pharynx for stretching Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Free surface of tissue Unstretched transitional epithelium Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lumen Basement membrane Free surface of tissue Stratified columnar epithelium Underlying connective tissue (a) (b) Basement membrane Free surface of tissue Connective tissue Stretched transitional epithelium (a) (b) Basement membrane Underlying connective tissue b: © The McGraw-Hill Companies, Inc./Al Telser, photographer (c) (d) b,d: © Ed Reschke

Glandular Epithelium Composed of cells that are specialized to produce and secrete substances There are two (2) types: Endocrine glands are ductless (key word: hormone) Exocrine glands have ducts Unicellular exocrine gland: Composed of one cell Goblet cell Multicellular exocrine gland: Composed of many cells Sweat glands, salivary glands, etc. Simple and compound

Structural Types of Exocrine Glands Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Tissue surface Duct Secretory portion Simple tubular Simple branched tubular Simple coiled tubular Simple branched alveolar Compound tubular Compound alveolar

Types of Glandular Secretions Merocrine Glands Fluid product Salivary glands Pancreas gland Sweat glands Apocrine Glands Portions of cells Mammary glands Ceruminous glands (earwax) Holocrine Glands Whole cells Sebaceous glands (oil) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pinched off portion of cell (secretion) Disintegrating cell and its contents (secretion) Intact cell Secretion New cell forming by mitosis and cytokinesis (a) Merocrine gland (b) Apocrine gland (c) Holocrine gland

Quiz! Gap junctions are found between cells 1.That form linings 2. In the skin 3. In the heart

Cell that line blood vessels, air sacs, and lymph vessels must allow substances to easily pass through them. These epithelial cells are typically Simple squamous Psuedostratified columnar Stratified cuboidal

Which type of gland secretes sweat? Epithelial Endocrine Exocrine

5.3: Connective Tissues General characteristics: Most abundant tissue type Many functions: Bind structures Provide support and protection Serve as frameworks Fill spaces Store fat Produce blood cells Protect against infections Help repair tissue damage Have a matrix In between cells – fibrin, collagen, etc Have varying degrees of vascularity Have cells that usually divide

Connective Tissue Major Cell Types Present Fibroblasts Fixed cell Most common cell Large, star-shaped Produce fibers Macrophages Wandering cell Phagocytic Important in injury or infection Mast cells Fixed cell Release heparin Release histamine

Connective Tissue Fiber Types Present Collagenous fibers Thick Composed of collagen Great tensile strength Abundant in dense CT Hold structures together Tendons, ligaments Elastic fibers Bundles of microfibrils embedded in elastin Fibers branch Elastic Vocal cords, air passages Reticular fibers Very thin collagenous fibers Highly branched Form supportive networks

Connective Tissues Connective Tissue Proper: Loose connective tissue Adipose tissue Reticular connective tissue Dense connective tissue Elastic connective tissue Specialized Connective Tissue: Cartilage Bone Blood

Connective Tissue Types Loose Connective Tissue Mainly fibroblasts Fluid to gel-like matrix Collagenous fibers Elastic fibers Bind skin to structures Beneath most epithelia Blood vessels nourish nearby epithelial cells Between muscles Adipose Tissue Adipocytes Cushions Insulates Store fats Beneath skin Behind eyeballs Around kidneys and heart Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cytsol Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Fat droplet Collagenous fiber Cell membrane Fibroblast Nucleus Ground substance (a) (b) Elastic fiber b: © The McGraw-Hill Companies, Inc./Dennis Strete, photographer (a) (b) b: © The McGraw-Hill Companies, Inc./Dennis Strete, photographer

Loose connective tissue Adipose tissue

Connective Tissue Types Reticular Connective Tissue Composed of reticular fibers Supports internal organ walls Walls of liver, spleen, lymphatic organs Dense Connective Tissue Packed collagenous fibers Elastic fibers Few fibroblasts Bind body parts together Tendons, ligaments, dermis Poor blood supply Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Fibroblasts Collagenous fibers Collagenous fibers White blood cell (a) (b) Fibroblast (a) (b) b: © The McGraw-Hill Companies, Inc./Dennis Strete, photographer b: © The McGraw-Hill Companies, Inc./Al Telser, photographer

Reticular connective tissue Dense connective tissue

Connective Tissue Types Bone (Osseous Tissue) Solid matrix Supports Protects Forms blood cells Attachment for muscles Skeleton Osteocytes in lacunae Elastic Connective Tissue Abundant in elastic fibers Some collagenous fibers Fibroblasts Attachments between bones Walls of large arteries, airways, heart Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display Collagenous fibers Osteon Lamella Fibroblast Central canal Elastic fibers Osteocyte in lacuna (a) (b) Canaliculi b: © The McGraw-Hill Companies, Inc./Al Telser, photographer (a) (b) Osteocyte Nucleus Cell process in canaliculus 21 b: © The McGraw-Hill Companies, Inc./Dennis Strete, photographer

Elastic connective tissue Osseous / Bone tissue

Connective Tissue Types Hyaline cartilage Most abundant Ends of bones Nose, respiratory passages Embryonic skeleton Cartilage Rigid matrix Chondrocytes in lacunae Poor blood supply Three (3) types: Hyaline Cartilage Elastic Cartilage Fibrocartilage Elastic cartilage Flexible External ear, larynx Fibrocartilage Very tough Shock absorber Intervertebral discs Pads of knee and pelvic girdle

Connective Tissue Types Three (3) types of cartilage: Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Elastic fibers Nucleus Nucleus Lacuna Lacuna Chondrocyte Chondrocyte Extracellular matrix Extracellular matrix (a) (b) (a) (b) b: © The McGraw-Hill Companies, Inc./Al Telser, photographer b: © The McGraw-Hill Companies, Inc./Al Telser, photographer Hyaline Cartilage Elastic Cartilage Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lacuna Chondrocyte Nucleus Collagenous fiber Extracellular matrix (a) (b) b: © The McGraw-Hill Companies, Inc./Al Telser, photographer Fibrocartilage

Connective Tissue Types Blood Fluid matrix called plasma Red blood cells White blood cells Platelets Transports Defends Involved in clotting Throughout body in blood vessels Heart Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. White blood cell Red blood cells Plasma (extracellular matrix of blood) Platelets (a) (b) b: © The McGraw-Hill Companies, Inc./Al Telser, photographer

Quiz! Tissue that stores fat is called ______ tissue. Epithelial Adipose 3. Reticular

Tendons and ligaments are what type of connective tissue? Dense connective tissue Osseous tissue Cartilage tissue

What type of tissue forms blood cells? Adipose Reticular connective tissue Osseous tissue

5.4: Types of Membranes There are four (4) types of epithelial membranes: 2. Mucous Membranes Line tubes and organs that open to outside world Lining of mouth, nose, throat, etc. Secrete mucus 1. Serous Membranes Line body cavities that do not open to the outside Reduce friction Inner lining of thorax and abdomen Cover organs of thorax and abdomen Secrete serous fluid 3. Cutaneous Membranes Covers body Skin 4. Synovial Membranes Composed entirely of connective tissue Lines joints

5.5: Muscle Tissues Skeletal muscle General characteristics: Attached to bones Striated Voluntary General characteristics: Muscle cells also called muscle fibers Contractile Three (3) types: Skeletal muscle Smooth muscle Cardiac muscle Smooth muscle Walls of organs Skin Walls of blood vessels Involuntary Non-striated Cardiac muscle Heart wall Involuntary Striated Intercalated discs

Muscle Tissue Skeletal Muscle Smooth Muscle Cardiac Muscle Striations Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Striations Cytoplasm Nuclei Nucleus Portion of a muscle fiber (a) (b) (a) (b) b: © The McGraw-Hill Companies, Inc./Dennis Strete, photographer b: © The McGraw-Hill Companies, Inc./Al Telser, photographer Skeletal Muscle Smooth Muscle Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Striations Nucleus Intercalated disc (a) (b) b: © The McGraw-Hill Companies, Inc./Al Telser, photographer Cardiac Muscle

5.6: Nervous Tissue Found in brain, spinal cord, and peripheral nerves Functional cells are neurons Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cellular process Neuroglial cells support and bind nervous tissue components Cytoplasm Nucleus Cell membrane Neuroglial cells (a) (b) Sensory reception b: © Ed Reschke. Conduction of nerve impulses

Quiz! Which type of membrane lines body cavities but does not open to the outside? Serous Mucous Synovial

What words describe skeletal muscle? Voluntary and nonstriated Voluntary and striated Involuntary and nonstriated