Chapter 5 Tissues - Hole's Essentials of Human Anatomy & Physiology PDF

Because learning changes everything.® Chapter 05 Tissues HOLE’S ESSENTIALS OF HUMAN ANATOMY & PHYSIOLOGY Fifteenth Edition Charles J. Welsh and Cynthia Prentice-Craver © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw...

Because learning changes everything.® Chapter 05 Tissues HOLE’S ESSENTIALS OF HUMAN ANATOMY & PHYSIOLOGY Fifteenth Edition Charles J. Welsh and Cynthia Prentice-Craver © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.  5.1: Introduction Similar cells are arranged in tissues that provide specific functions for the body Cells of different tissues are structured differently, which leads to their differences in function The tissues of the human body include 4 major types: Epithelial tissues: form protective coverings and function in secretion and absorption Connective tissues: support soft parts and bind structures together Muscular tissues: produce body movement Nervous tissue: conduct impulses to control and coordinate body activities © McGraw Hill, LLC 2  Tissues 1 TABLE 5.1 Tissues Type Function Location Distinguishing Characteristics Epithelial Protection, secretion, Cover body surface, Lack blood vessels, readily divide; cells absorption, excretion cover and line internal are tightly packed organs, compose glands Connective Bind, support, protect, Widely distributed Most have a rich supply of blood, with fill spaces, store fat, throughout body at least two distinct cell types; cells produce blood cells are farther apart than epithelial cells with extracellular matrix in between Muscle Movement Attached to bones, in Able to generate force in response to the walls of hollow specific stimuli internal organs, heart Nervous Conduct impulses for Brain, spinal cord, Cells communicate with each other coordination, nerves and other body parts by receiving and regulation, integration, sending stimuli and sensory reception © McGraw Hill, LLC 3  Tissues 2 Tissues are 3-dimensional structures Micrographs: photos of very thin sections of tissue specimens By observing micrographs, the microscopic structure of tissues can be studied Tubular body structures can be observed through micrographs: Circles or ovals indicate cross or oblique sections Rows of cells with an elongated space between them indicate longitudinal sections © McGraw Hill, LLC 4  Figure 5.1: Tissue Sections (a): Al Telser/McGraw Hill; (b): Victor P. Eroschenko Access the text alternative for these images © McGraw Hill, LLC 5  5.2: Epithelial Tissues General Characteristics of Epithelial Tissues: Widespread throughout the body Cover organs and the body surface, line cavities and hollow organs, and make up glands Have a free (apical) surface exposed to the outside or internally to an open space Anchored to underlying connective tissues by a basement membrane Made up of tightly packed cells containing little intercellular material Readily divide Lack blood vessels, but are nourished by cells in underlying connective tissues © McGraw Hill, LLC 6  Epithelial Tissues Epithelial tissues function in protection, secretion, absorption, and excretion Classified by cell shape and the number of cell layers: Cell shapes: squamous (thin and flattened), cuboidal (cube- shaped), or columnar (tall and elongated) Number of layers: simple (1 layer) and stratified (2 or more layers) Free surfaces can be modified to reflect specific functions, such as presence of cilia or microvilli © McGraw Hill, LLC 7  Simple Squamous Epithelium Simple squamous epithelium: Made up of a single layer of thin, flattened cells Cells are tightly packed together Cells have broad, thin nuclei Due to flattened structure of cells, this type is found in diffusion and filtration sites Because it is suited for diffusion, it functions in the exchange of gases in the alveoli of the lungs, and lines blood and lymph vessels, as well as body cavities It is very delicate, and can be damaged easily © McGraw Hill, LLC 8  Figure 5.2: Simple Squamous Epithelium (b): Al Telser/McGraw Hill; (c): Ed Reschke/Photolibrary/Stone/Getty Images Access the text alternative for these images © McGraw Hill, LLC 9  Simple Cuboidal Epithelium Consists of a single layer of cube-shaped cells with centrally located nuclei Lines most kidney tubules, covers ovaries, and lines ducts of some glands Functions in urine formation in the kidneys, and glandular secretion When it lines tubules or ducts, free surface faces lumen, a hollow channel © McGraw Hill, LLC 10  Figure 5.3: Simple Cuboidal Epithelium (b): Victor P. Eroschenko Access the text alternative for these images © McGraw Hill, LLC 11  Simple Columnar Epithelium 1 Simple columnar epithelium: Made up of one row of tall, elongated cells Nuclei are located near the basement membrane Cells may be ciliated or nonciliated Nonciliated cells line the uterus, stomach, and intestines, where they protect underlying tissues, secrete digestive fluids, and absorb nutrients © McGraw Hill, LLC 12  Simple Columnar Epithelium 2 Cilia are long extensions from the free surfaces of certain cells; they beat in a certain direction to move cells or mucus Ciliated cells are found in the uterine tubes, and help move egg cells toward the uterus Some cells contain tiny microvilli (smaller than cilia) to increase surface area for absorption Goblet cells are scattered among the cells; secrete mucus onto the free surface of the tissue for lubrication or protection © McGraw Hill, LLC 13  Figure 5.4: Simple Columnar Epithelium (b): Victor P. Eroschenko Access the text alternative for these images © McGraw Hill, LLC 14  Pseudostratified Columnar Epithelium Cells appear layered due to the varying positions of their nuclei within the row of cells, but are not truly layered Cells vary in shape All cells reach basement membrane, but not all reach free surface Most cells have cilia along their free surface Goblet cells are scattered among the epithelial cells; secrete mucus Found in the passageways of the respiratory system In the respiratory tract, the mucus traps microorganisms and dust, and the cilia sweep them away from the airways © McGraw Hill, LLC 15  Figure 5.5: Pseudostratified Columnar Epithelium (b): Dennis Strete/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 16  Stratified Squamous Epithelium Made up of many layers of flattened cells, designed to protect underlying layers Named for the shape of the outermost layers of cells, which are composed of squamous cells Cuboidal cells in the deeper layers divide, and push the older cells outward, where they begin to flatten Makes up the outer layer of skin (epidermis), and lines the mouth, esophagus, vagina, and anal canal In the skin, outer layers of cells undergo keratinization, producing a dry, water-proof, protective layer, in which outer cells are dead Keratinization does not occur in areas in which tissues remain moist and alive: oral cavity, esophagus, vagina, or anal canal © McGraw Hill, LLC 17  Figure 5.6: Stratified Squamous Epithelium (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 18  Stratified Cuboidal Epithelium Consists of 2 to 3 layers of cuboidal cells Forms lining of a lumen Provides greater protection than a single cell layer Lines ducts of the mammary glands, sweat glands, salivary glands, pancreas, ovarian follicles, and seminiferous tubules © McGraw Hill, LLC 19  Figure 5.7: Stratified Cuboidal Epithelium (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 20  Stratified Columnar Epithelium Consists of several layers of cells Has columnar cells on the surface and cuboidal cells in the basal layers A rare type od tissue Found in the male urethra and linings of large gland ducts © McGraw Hill, LLC 21  Figure 5.8: Stratified Columnar Epithelium (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 22  Transitional Epithelium Designed to distend (stretch) and return to its normal size, in response to changing tension Found in the linings of the urinary bladder, urethra, and ureters Upon contraction of a wall of one of these organs, the tissue is composed of several layers of cells of irregular shape Upon distension, the cells become elongated Functions as an expandable lining, and prevents urine from diffusing back into the internal environment © McGraw Hill, LLC 23  Figure 5.9: Transitional Epithelium (b, d): Ed Reschke Access the text alternative for these images © McGraw Hill, LLC 24  Types of Epithelial Tissues TABLE 5.2 Epithelial Tissues Type Function Location Simple squamous Filtration, diffusion, Air sacs of the lungs, walls of capillaries, linings of blood epithelium osmosis; covers surface and lymph vessels, part of the membranes lining body cavities and covering viscera Simple cuboidal Protection, secretion Surface of ovaries, linings of kidney tubules, and linings of epithelium ducts of certain glands Simple columnar Protection, secretion, Linings of uterus, stomach, and intestines epithelium absorption Pseudostratified Protection, secretion, Linings of respiratory passages columnar epithelium movement of mucus Stratified squamous Protection Superficial layer of skin, and linings of oral cavity, throat, epithelium vagina, and anal canal Stratified cuboidal Protection Linings of ducts of mammary glands, sweat glands, epithelium salivary glands, and pancreas Stratified columnar Protection, secretion Part of the male urethra and linings of larger ducts of epithelium excretory glands Transitional epithelium Stretchability, protection Inner lining of urinary bladder and linings of ureters and part of urethra © McGraw Hill, LLC 25  Glands Organs composed of epithelial tissues Made up of cuboidal or columnar cells Produce and secrete substances into ducts or into body fluids: Glands that secrete products into ducts that open to a body surface are exocrine glands Glands that secrete products into body fluids or blood are endocrine glands © McGraw Hill, LLC 26  Classification of Exocrine Glands Exocrine glands are classified by the ways the glands secrete their products: Merocrine (eccrine) glands are the most common type; release fluid products by exocytosis: Some are serous; produce a watery serous fluid, sometimes with high enzyme concentration Others are mucous; produce a thicker, protective substance (mucus) Examples: pancreas, salivary glands, and sweat glands Apocrine glands pinch off a portion of their cell bodies during secretion; example: mammary glands Holocrine glands release entire cells that disintegrate to release their secretions; example: sebaceous (oil) glands © McGraw Hill, LLC 27  Figure 5.10: Types of Exocrine Glands Access the text alternative for these images © McGraw Hill, LLC 28  Exocrine Gland Secretions TABLE 5.3 Exocrine Glandular Secretions Type of Gland Description of Secretion Example Merocrine glands A fluid product released Salivary glands, pancreatic through the cell membrane by glands, sweat glands of the exocytosis skin Apocrine glands Cellular product and portions Mammary glands, of the free ends of glandular ceruminous glands lining cells pinch off during secretion the external ear canal Holocrine glands Disintegrated entire cells filled Sebaceous glands of the with secretory products skin © McGraw Hill, LLC 29  5.3: Connective Tissues General characteristics of connective tissues: Functions: Bind, support, protect, serve as frameworks, fill spaces, store fat, produce blood cells, protect against infection, and help repair tissue damage Unlike epithelial tissues, connective tissue cells lie far apart from each other Have an abundance of extracellular matrix, or intercellular material, composed of protein fibers and ground substance Consistency varies from liquid to rigid, depending on the ground substance Most connective tissues can divide Most have a rich blood supply (except cartilage) © McGraw Hill, LLC 30  Figure 5A: The Extracellular Matrix of Connective Tissue Access the text alternative for these images © McGraw Hill, LLC 31  Major Cell Types of Connective Tissues Categories of connective tissue cells: Fixed: stay in a tissue for a long time Wandering: can move through tissues in response to infection or injury; stay in a tissue temporarily Major cell types: Fibroblasts: most common fixed cell type; large, star-shaped cells that secrete fibers Macrophages (histiocytes): function as phagocytes; defend against infection and foreign particles Mast cells: large, fixed cells, located near blood vessels; release heparin (anticoagulant) and histamine (promotes inflammation) © McGraw Hill, LLC 32  Figure 5.11: Fibroblasts Juergen Berger/Science Source © McGraw Hill, LLC 33  Figure 5.12: A Macrophage Engulfing a Bacterium Biology Pics/Science Source © McGraw Hill, LLC 34  Figure 5.13: A Mast Cell Steve Gschmeissner/Science Source © McGraw Hill, LLC 35  Connective Tissue Fibers Fibroblasts produce the 3 types of fibers found in connective tissues: Collagen (white) fibers: thick threads of collagen protein; found in long, parallel bundles; high tensile strength to hold structures together, but not very elastic; examples: tendons, ligaments Elastic (yellow) fibers: made of the protein elastin; occur in thin branching fibers arranged in a network; stretchy and add flexibility to certain types of connective tissues; example: vocal cords Reticular fibers: thin collagen fibers that form branching, supportive networks in a variety of tissues; example: spleen © McGraw Hill, LLC 36  Components of Connective Tissue TABLE 5.4 General Components of Connective Tissue Component Function Cellular Fibroblasts Produce fibers Macrophages Carry on phagocytosis Mast cells Secrete heparin and histamine Extracellular (matrix) Collagen fibers Hold structures together with great tensile strength Elastic fibers Stretch easily Reticular fibers Lend delicate support Ground substance Fills in spaces around cells and fibers © McGraw Hill, LLC 37  Categories of Connective Tissue Main categories of connective tissue: Connective tissue proper: Loose connective tissue Dense connective tissue Specialized connective tissue: Cartilage Bone Blood © McGraw Hill, LLC 38  Loose Connective Tissue 1 Types of loose connective tissues: Areolar tissue: Forms thin, delicate membranes Main cell type is fibroblasts Matrix consists of a gel-like ground substance containing collagen and reticular fibers Locations: binds skin to underlying tissues, under most epithelial layers, between muscles Adipose tissue (fat): Contains adipocytes, which store fat in cytoplasm Found under skin, between muscles, around kidneys, around abdominal membranes, behind eyeballs Functions: Cushions joints & organs, stores energy, insulates body © McGraw Hill, LLC 39  Loose Connective Tissue 2 Reticular connective tissue: Contains thin, reticular fibers Fibers form a 3-dimensional network Forms a framework for certain internal organs (liver, spleen) © McGraw Hill, LLC 40  Figure 5.14: Areolar Tissue (b): Dennis Strete/ McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 41  Figure 5.15: Adipose Tissue (b): Alvin Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 42  Dense Connective Tissue Consists of densely packed collagen fibers and a network of elastic fibers Contains few cells; most are fibroblasts Due to strength of collagen fibers, the tissue can withstand pulling forces Has a poor blood supply, so heals slowly Found in tendons, ligaments, deep layer of skin, and the white layer of the eyeball (sclera) © McGraw Hill, LLC 43  Figure 5.16: Dense Connective Tissue (b): Dennis Strete/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 44  Cartilage A rigid connective tissue Provides a supportive framework for various structures, protects underlying tissues, serves as models for developing bones Lacks a vascular system, so heals slowly, and cells do not divide often Abundant matrix, with collagen fibers in a gel-like ground substance Chondrocytes (cartilage cells) lie within lacunae (chambers) in the matrix Cartilaginous structures are enclosed within a connective tissue covering called the perichondrium The 3 types of cartilage differ by their type of matrix © McGraw Hill, LLC 45  Three Types of Cartilage Hyaline cartilage: The most common type of cartilage Contains fine collagen fibers in matrix; appears glassy Found on the ends of bones, supports respiratory structures and passages, also important in embryonic development of many bones and bone growth Elastic cartilage: Contains elastic fibers in dense network; flexible Provides framework for the external ears and parts of the larynx Fibrocartilage: Tough tissue containing many collagenous fibers Good shock absorber Found in intervertebral discs, knees and pelvic girdle © McGraw Hill, LLC 46  Figure 5.17: Hyaline Cartilage (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 47  Figure 5.18: Elastic Cartilage (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 48  Figure 5.19: Fibrocartilage (b): Victor P. Eroschenko Access the text alternative for these images © McGraw Hill, LLC 49  Bone (Osseous Tissue) 1 Bone: The most rigid connective tissue, due to presence of mineral salts (calcium salts) Collagen fibers within the matrix provide some flexibility Bone supports and protects many body structures in cranial & thoracic cavities Forms sites for muscle attachments Site of blood cell formation (red bone marrow) Stores and releases chemicals, such as calcium and phosphorus © McGraw Hill, LLC 50  Bone (Osseous Tissue) 2 2 types of bone tissue: compact and spongy Structure of compact bone: Bone cells, called osteocytes, lie within lacunae (chambers) Matrix is arranged in concentric circles (lamellae) around central or Haversian canals Cylindrical units are called osteons or Haversian systems Central canals contain blood vessels, and distribute blood to the cells through tiny tubes called canaliculi Bone has a good blood supply, enabling rapid recovery after an injury © McGraw Hill, LLC 51  Figure 5.20: Bone Tissue, Osteons, and Osteocytes (b): Dennis Strete/McGraw Hill; (c): Prof. P. Motta/ Department of Anatomy/University, “La Sapienza,” Rome/Science Source Access the text alternative for these images © McGraw Hill, LLC 52  Blood Functions to transport substances throughout the body Transports substances between interior cells and cells that exchange nutrients, gases, and wastes with the environment Composed of formed elements suspended in a liquid matrix called plasma. Formed elements include red blood cells to carry oxygen, white blood cells for protection against infection, and platelets for blood clotting Most blood cells are produced by the red bone marrow within certain long bones © McGraw Hill, LLC 53  Figure 5.21: Blood (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 54  Summary: Connective Tissues TABLE 5.5 Connective Tissues Type Function Location Loose connective tissue Areolar tissue Binds organs Beneath skin, between muscles, beneath epithelial tissues Adipose tissue Protects, insulates, stores fat Beneath skin, around kidneys, behind eyeballs, on surface of heart Reticular connective tissue Supports In walls of liver and spleen Dense connective tissue Binds body parts Tendons, ligaments, deep layer of skin Specialized connective tissue Hyaline cartilage Supports, protects, provides Ends of bones, nose, rings in the walls of respiratory framework passages Elastic cartilage Supports, protects, provides flexible Framework of external ear and parts of larynx framework Fibrocartilage Supports, protects, provides Between bony parts of spinal column, parts of pelvic framework girdle and knee Bone Supports, protects, absorbs shock Bones of skeleton Blood Transports substances, helps maintain Throughout body within a closed system of blood stable internal environment vessels and heart chambers © McGraw Hill, LLC 55  5.4: Types of Membranes There are 4 types of membranes in the body: 3 types of epithelial membranes and 1 type of connective tissue membrane Epithelial membranes are thin, sheet-like structures composed of epithelium and connective tissues, covering body surfaces and lining body cavities; there are 3 types: Serous membranes Mucous membranes Cutaneous membrane Connective tissue membranes: Synovial membranes Line joints and are composed entirely of connective tissue © McGraw Hill, LLC 56  Types of Epithelial Membranes 1 Serous membranes: Line cavities that do not open to the outside (thoracic and abdominal cavities) Consist of simple squamous epithelium and a layer of areolar connective tissue Examples: pleura, pericardium, and peritoneum Exist as double-layered membranes: Outer parietal portion lines the cavity wall Inner visceral portion covers the organs Contain a small amount of lubricating serous fluid between the 2 layers, which is secreted by cells of the membrane © McGraw Hill, LLC 57  Types of Epithelial Membranes 2 Mucous membranes: Line cavities and tubes that open to the outside of body Consist of some type of epithelium and a layer of areolar connective tissue Contain goblet cells that produce mucus Include oral and nasal cavities, and tubular organs of the digestive, respiratory, urinary, and reproductive systems Cutaneous membrane: The skin A dry membrane that is keratinized for protection and water- proofing © McGraw Hill, LLC 58  5.5: Muscle Tissues General characteristics of muscle tissues: Muscle cells, or muscle fibers, have ability to generate force, contract and shorten to provide movement 3 types of muscle tissue: skeletal, smooth and cardiac 40% of body weight is skeletal muscle, and 10% is smooth and cardiac muscle © McGraw Hill, LLC 59  Skeletal Muscle Tissue Makes up muscles that attach to bones Voluntary; can be controlled by conscious effort Cells (fibers) are long and cylindrical, striated (have a striped appearance), have many nuclei Cells contract only when stimulated by nerve cells (neurons) Skeletal muscles move head, trunk, and limbs © McGraw Hill, LLC 60  Figure 5.22: Skeletal Muscle Tissue (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 61  Smooth Muscle Tissue Smooth muscle tissue: Named because smooth muscle cells lack striations Cells are spindle-shaped, with 1 central nucleus Involuntary, since it cannot be stimulated to contract with conscious effort Found in the walls of hollow internal organs, such as in the digestive tract, blood vessels, and urinary bladder © McGraw Hill, LLC 62  Figure 5.23: Smooth Muscle Tissue (b): Al Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 63  Cardiac Muscle Tissue Found only in the heart Consists of branching cells (fibers), each with a single nucleus Cells form branching networks Cells are connected to each other by intercalated discs, containing special gap junctions that send impulses from cell to cell Involuntary; cannot be controlled by conscious effort Striated; has a striped appearance Makes up most of the heart Pumps blood through heart and into blood vessels © McGraw Hill, LLC 64  Figure 5.24: Cardiac Muscle Tissue (b): Al Telser/ McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 65  Summary: Types of Muscle Tissues TABLE 5.6 Muscle Tissues Type Function Location Skeletal muscle tissue Voluntary movements Muscles usually attached to (striated) of skeletal parts bones Smooth muscle Involuntary Walls of hollow internal organs tissue (lacks movements of striations) internal organs Cardiac muscle tissue Contraction for heart Heart muscle (striated) beats © McGraw Hill, LLC 66  5.6: Nervous Tissue Nervous tissue: Found in the brain, spinal cord, and nerves Neurons, or nerve cells: Cells that respond to certain types of environmental stimuli or changes, by conducting electrical impulses to other neurons, muscles, and glands Consist of a soma (cell body), and cellular processes (extensions), called dendrites (receive stimuli) and axons (send out signals) Coordinate and regulate body functions Neuroglia (nerve glue): Cells that support, nourish, and communicate with neurons, but do not conduct impulses Bind nervous tissue together, conduct phagocytosis © McGraw Hill, LLC 67  Figure 5.25: Neuron Structure and Nervous Tissue (b): Alvin Telser/McGraw Hill Access the text alternative for these images © McGraw Hill, LLC 68  Because learning changes everything. ® www.mheducation.com © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.