BIOL 1110-API- Tissues-Fall 24.RZ (1)_compressed PDF

www.udst.edu.qa Chapter 5 The Human Tissues ANATOMY & PHYSIOLOGY The Unity of Form and Function TENTH EDITION KENNETH S. SALADIN © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC....

www.udst.edu.qa Chapter 5 The Human Tissues ANATOMY & PHYSIOLOGY The Unity of Form and Function TENTH EDITION KENNETH S. SALADIN © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 1. Explain how epithelial tissue is categorized by shape and arrangement of cells. 2. Explain glandular epithelia and moods of secretion. 3. List and briefly discuss the major types of connective tissue. 4. Define matrix (extracellular matrix) and discuss how it may affect the function of a tissue. 5. Compare and contrast the three major types of muscle tissue. 6. Describe the function of nervous tissue and list the three structural components of a neuron.  Introduction Figure 1 An Orientation to the Tissues of the Body  Introduction There are 50 trillion cells of 200 different cell types Four broad categories of tissues: Epithelial tissue Connective tissue Nervous tissue Muscular tissue Organ—structure with discrete boundaries that is composed of two or more tissue types Histology (microscopic anatomy)—the study of tissues and how they are arranged into organs 5  5.1 The Study of Tissues Expected Learning Outcomes: – Name the four primary classes into which all adult tissues are classified. – Name the three embryonic germ layers and some adult tissues derived from each. – Visualize the three-dimensional shape of a structure from a two- dimensional tissue section. 6  5.1a The Primary Tissue Classes Tissue—a group of similar cells and cell products working together to perform a specific role in an organ The four primary tissues (epithelial, connective, nervous, and muscular) differ from each other in: Types and functions of their cells Characteristics of the matrix (extracellular material) Relative amount of space occupied by cells and matrix Matrix (extracellular material) is composed of: Fibrous proteins Clear gel called ground substance » Also known as tissue fluid, extracellular fluid (ECF), or interstitial fluid » Contains water, gases, minerals, nutrients, wastes, hormones 7  5.1b Embryonic Tissues Human development begins with a fertilized egg, which divides and produces first tissue layers Three primary germ layers: – Ectoderm (outer) Gives rise to epidermis and nervous system – Endoderm (inner) Gives rise to mucous membrane lining digestive and respiratory tracts, digestive glands, among other things – Mesoderm (middle) becomes gelatinous tissue called mesenchyme Wispy collagen fibers and fibroblasts in gel matrix Gives rise to cartilage, bone, blood 8  5.1c Interpreting Tissue Sections 1 Understanding histology requires awareness of how specimens are prepared Histologists use histological sections—tissue sliced into thin sections one or two cells thick Fixative prevents decay (formalin) Stains color the tissue, bind to different cellular components Sectioning reduces three-dimensional structure to two- dimensional slice – Longitudinal section (l.s.)—tissue cut on its long axis – Cross section (c.s.) or transverse section (t.s.)—tissue cut perpendicular to long axis of organ – Oblique section—tissue cut at angle between cross and longitudinal sections 9 Three-Dimensional Interpretation of Two-Dimensional Images Figur Access the text alternative for slide images. e 5.1 10 Three Planes of Section Figur Access the text alternative for slide images. e 5.2 11  Interpreting Tissue Sections 2 Not all tissues are sectioned Smear—tissue is rubbed or spread across a slide Examples: Blood and soft tissues like the spinal cord Spread—tissues are laid out on a slide Examples: Membranes and “cobwebby” tissues like areolar tissue 12  5.2 Epithelial Tissue 1 Expected Learning Outcomes: – Describe the properties that distinguish epithelium from other tissue classes. – List and classify eight types of epithelium, distinguish them from each other, and state where each type can be found in the body. – Explain how the structural differences between epithelia relate to their functional differences. – Visually recognize each epithelial type from specimens or photographs. 13  Epithelial Tissue 2 Epithelial tissue—sheet of closely adhering cells, one or more cells thick, with upper surface exposed to environment or internal space Covers body surfaces and lines body cavities Constitutes most glands Avascular (does not have blood vessels) Usually nourished by underlying connective tissue 14  Epithelial Tissue 3 Functions of epithelial tissue: – Protection—protect deeper tissues from injury and infection – Secretion—produce and release mucus, sweat, enzymes, hormones, and other substances – Excretion—void wastes from the tissues – Absorption—absorb chemicals, such as nutrients – Filtration—all substances leaving the body are selectively filtered by an epithelium – Sensation—nerve endings in epithelia detect stimuli 15  Epithelial Tissue 4 General structure of epithelia: Cells close together, small amount of extracellular material Avascular—no blood vessels, nourished by underlying connective tissue High rate of mitosis in cells near connective tissue Rest on a basement membrane—layer between an epithelium and underlying connective tissue Collagen, glycoproteins, other protein–carbohydrate complexes Anchors the epithelium to the connective tissue below it 16  Epithelial Tissue 5 General structure of epithelia (continued): Surfaces of epithelial cells: – Basal surface—surface facing the basement membrane – Apical surface—surface that faces away from the basement membrane – Lateral surface—surface between the basal and apical surface, the “sidewall” Epithelia classified by number of cell layers – Simple epithelia have each cell anchored to basement membrane – Stratified epithelia have cells on top of others, so not all contact the basement membrane 17 Courtesy Barbara Cousins. Cell Shapes and Epithelial Types Access the text alternative for slide images. Figure 5.3 19  5.2a Simple Epithelia 1 A simple epithelium has a single layer of cells Three types named by the shapes of their cells Simple squamous (thin, scaly cells) Simple cuboidal (squarish or round cells) Simple columnar (tall, narrow cells) – In the fourth type, pseudostratified columnar, not all cells reach the surface but all reach the basement membrane Falsely appears stratified, as some cells taller than others Goblet cells—wineglass-shaped mucus-secreting cells in simple columnar and pseudostratified epithelia 20  Simple Squamous Epithelium a: Al Telser/McGraw-Hill Figure 5.4 – Single row of thin cells – Permits rapid diffusion or transport of substances – Secretes serous fluid – Locations: alveoli, glomeruli, endothelium, and serosa Access the text alternative for slide images. 21  Simple Cuboidal Epithelium a: Dennis Strete/McGraw-Hill Figure 5.5 – Single layer of square or round cells – Absorption and secretion, mucus production and movement – Locations: liver, thyroid, mammary and salivary glands, bronchioles, and Access the textkidney tubules alternative for slide images. 22  Simple Columnar Epithelium a: Ed Figure Reschke/Photolibrary/Stone/Getty Images 5.6 – Single row of tall, narrow cells – Oval nuclei in basal half of cell – Brush border of microvilli, sometimes ciliated, may possess goblet cells – Absorption and secretion; secretion of mucus – Locations: lining of GI tract, uterus, kidney, and uterine tubes Access the text alternative for slide images. 23  Ciliated Pseudostratified Columnar Epithelium a: Dennis Figure Strete/McGraw-Hill 5.7 – Looks multilayered, but all cells touch basement membrane – Nuclei at several layers – Has cilia and goblet cells – Secretes and propels mucus – Locations: respiratory tract and portions of male urethra Access the text alternative for slide images. 24  5.2b Stratified Epithelia 1 Stratified epithelia range from 2 to 20 or more layers of cells Some cells rest directly on others; only the deepest layer attaches to basement membrane Three stratified epithelia are named for the shapes of their surface cells Stratified squamous Stratified cuboidal Stratified columnar – A fourth type, the urothelium, is unique to the urinary tract Previously called transitional epithelium 25  Stratified Epithelia 2 Stratified columnar is rare, only in places where two other epithelial types meet Stratified squamous is most widespread – Deepest cells are cuboidal to columnar, include mitotically active stem cells » Daughter cells push toward the surface and become flatter as they migrate upward » Finally die and flake off—exfoliation (desquamation) – Two kinds of stratified squamous epithelia: » Keratinized (cornified)—found on skin surface, abrasion resistant » Nonkeratinized—found lining internal spaces, lacks surface layer of dead cells 26  Keratinized Stratified Squamous Epithelium a: Ed Reschke Figure 5.8 – Multiple cell layers; cells become flat and scaly toward surface – Resists abrasion; retards water loss through skin; resists penetration by pathogenic organisms – Locations: epidermis; palms Access andfor soles the text alternative images. slide heavily keratinized 27  Nonkeratinized Stratified Squamous Epithelium a: Ed Reschke/Stone/Getty Images Figure 5.9 – Same as keratinized epithelium without surface layer of dead cells – Resists abrasion and penetration of pathogens – Locations: tongue, oral mucosa, esophagus, and vagina Access the text alternative for slide images. 28  Stratified Cuboidal Epithelium a: Lester V. Bergman/Corbis NX/Getty Images Figure 5.10 – Two or more cell layers; surface cells square or round – Secretes sweat; produces sperm, produces ovarian hormones – Locations: sweat gland ducts; ovarian follicles and Access the text alternative for slide seminiferous tubules images. 29  Urothelium a: Johnny R. Figure Howze/McGraw-Hill 5.11 – Multilayered epithelium with surface cells that change from round to flat when stretched – Allows for filling of urinary tract – Locations: ureter and bladder Access the text alternative for slide images. 30 Transitional epithelium: Figure 3.5c Transitional Epithelia  5.5b Glands Gland—cell or organ that secretes substances for use elsewhere in the body or releases them for elimination from the body – Usually composed of epithelial tissue in a connective tissue framework and capsule – Secretion—product useful to the body – Excretion—waste product 32  Endocrine and Exocrine Glands 1 Glands are classified as exocrine or endocrine Exocrine glands—maintain their contact with surface of epithelium by way of a duct Surfaces can be external (e.g., sweat, tear glands) or internal (e.g., pancreas, salivary glands) Endocrine glands—have no ducts but do have many blood capillaries; secrete hormones directly into blood Hormones: chemical messengers that stimulate cells elsewhere in the body Examples: thyroid, adrenal, and pituitary glands 33  Endocrine and Exocrine Glands 2 Glands (continued): Unicellular glands—secretory cells found in an epithelium that is predominantly non-secretory Can be exocrine or endocrine Examples: mucus-secreting goblet cells in trachea or endocrine cells of stomach 34 Development of Exocrine and Endocrine Glands Access the text alternative for slide images. Figure 5.29 35  Exocrine Gland Structure 2 Exocrine glands are classified by the structure of their ducts and secretory portions – Duct shape: Simple—unbranched Compound—branched – Secretory portions: Tubular—narrow secretory portion, duct and secretory portion are of uniform diameter Acinar—secretory cells form dilated sac (acinus or alveolus) Tubuloacinar (tubuloalveolar)—secretory cells are in both tubular and acinar portions 36 Some Types of Exocrine Glands Access the text alternative for slide images. Figure 5.31 37  Glandular Epithelia Figure 3.8 A Structural Classification of Simple and Compound ExocrineGlands  Types of Secretions Glands are also classified by their secretions Serous glands—produce thin, watery secretions Perspiration, milk, tears, digestive juices Mucous glands—produce glycoprotein called mucin, which absorbs water to form mucus Goblet cells: unicellular mucous glands Mixed glands—contain both serous and mucous cell types and produce a mixture of the two types of secretions – Example: the two pairs of salivary glands in the chin 39  Glandular Epithelia Figure 3.7 Mucous and Mixed Glandular Epithelia  Modes of Secretion Exocrine glands classified according to how their secretions are released Eccrine (merocrine) glands—release their products by exocytosis Examples: tear glands, pancreas, gastric glands, and others Apocrine secretion—lipid droplet covered by membrane and cytoplasm buds from cell surface Mode of milk fat secretion by mammary gland cells Holocrine secretion—cells accumulate a product and entire cell disintegrates Secrete a mixture of cell fragments and synthesized substances Examples: oil glands of scalp and skin, and glands of eyelids 41 The Three Modes of Exocrine Secretion Access the text alternative for slide images. Figure 5.32 42 Glandular Epithelia: Modes of Secretion Figure 3.9 Mechanisms of Glandular Secretions Figure 3.10 A Classification of Connective Tissues  5.3a Connective Tissue Overview 1 Connective tissue—most abundant, widely distributed, and variable type of tissue in which cells occupy less space than matrix – Most cells are not in direct contact with each other Highly variable vascularity Loose connective tissues have many blood vessels Cartilage has no blood vessels 45  Connective Tissue Overview 2 Functions of connective tissues: – Binding of organs—connect one bone to another, muscles, to bones, skin to muscle, and hold organs in place – Support—support the body and its organs, form internal framework of organs – Physical protection—protect, cushion delicate organs – Immune protection—connective tissue cells attack foreign invaders 46  Connective Tissue Overview 3 Functions of connective tissues (continued): – Movement—bones provide lever system for body movement, cartilages involved in speech – Storage—maintain stores of fat, calcium, phosphorus – Heat production—metabolism of brown fat generates heat – Transport—blood transports gases, nutrients, wastes, hormones, blood cells 47  Connective Tissues All connective tissues (CT) have three main components: – Special cells – Extracellular protein fibers – Ground substance  Fibrous Connective Tissue 2 Components of fibrous connective tissue (continued): Fibers: Collagenous fibers made of collagen » Tough, flexible, and stretch-resistant » Called white fibers due to appearance in fresh tissue » Tendons, ligaments, and deep layer of the skin are mostly collagen » Less visible in the matrix of cartilage and bone Reticular fibers » Thin collagen fibers coated with glycoprotein » Form framework of spleen and lymph nodes; part of basement membranes under epithelia Elastic fibers » Thinner than collagenous fibers; made of protein elastin » Allows stretch and recoil like a rubber band 49  Matrix: Is the collective term for the extracellular component of any connective tissue that is made up of the protein fibers and the ground substance. Tissues differ in the amount and kind of fluid material between the cells Matrix is also called the extracellular matrix (ECM) The matrix varies in amount and composition among the various tissues Epithelial tissues have very little matrix because the cells are so closely connected Connective Tissue Proper: Cells Table 3.1 Cells of Connective Tissue Tendons and Ligament Rebecca Gray/McGraw-Hill Education Access the text alternative for slide images. Figure 5.13 52  Types of Fibrous Connective Tissue 1 Two broad categories: Loose and dense connective tissue Loose connective tissue—mostly ground substance in space surrounding cells Types: areolar and reticular Dense connective tissue—mostly fibers in space surrounding cells Types: dense regular and dense irregular 53  Areolar Tissue a: Dennis Strete/McGraw-Hill Figure 5.14 – Loosely organized fibers, abundant blood vessels – Possesses all six cell types and fiber types – Underlies epithelia, in serous membranes, between muscles, passageways for nerves and blood vessels Access the text alternative for slide images. 54  Reticular Tissue a: McGraw- Figure Hill/Al Telser 5.15 – Mesh of reticular fibers and fibroblasts – Forms supportive stroma (framework) for lymphatic organs – Found in lymph nodes, spleen, thymus, and bone Access the text alternative for slide images. marrow 55  Dense Regular Connective Tissue a: Dennis Strete/McGraw-Hill Figure Education 5.16 – Densely packed, parallel collagen fibers – Compressed fibroblast nuclei – Elastic tissue forms wavy sheets in some locations – Tendons attach muscles to bones and ligaments hold bones together Access the text alternative for slide images. 56  Dense Irregular Connective Tissue a: McGraw-Hill /Dennis Figure Strete 5.17 – Densely packed, randomly arranged, collagen fibers and few visible cells – Withstands unpredictable stresses – Locations: deeper layer of skin; capsules around Access the text alternative for slide organs6 images. 57  5.3c Adipose Tissue 1 Adipose tissue (fat)—tissue in which adipocytes are the dominant cell type Space between adipocytes is occupied by areolar tissue, reticular tissue, and blood capillaries Fat is the body’s primary energy reservoir The quantity of stored triglyceride and the number of adipocytes are quite stable in a person Fat is recycled continuously » New triglycerides synthesized while old molecules hydrolyzed and released to blood 58  Adipose Tissue 2 Two types in humans: white (or yellow) fat and brown fat White adipose tissue (WAT, or white fat) is the most abundant and significant type in adults Provides thermal insulation Cushions organs such as eyeballs, kidneys Contributes to body contours—female breasts and hips Secretes hormones that regulate metabolism Brown adipose tissue (BAT, or brown fat) is found mainly in fetuses, infants, children Adults have smaller deposits of it Color comes from blood vessels, mitochondria, and mitochondrial enzymes Functions as a heat-generating tissue 59  White Adipose Tissue a: Dennis Figure Strete/McGraw-Hill 5.18 – Empty-looking cells with thin margins; nucleus pressed against cell membrane – Energy storage, insulation, cushioning – Brown fat produces heat Access the text alternative for slide images. 60  5.3d Cartilage 1 Cartilage—stiff connective tissue with flexible, rubbery matrix Gives shape to ear, tip of nose, and larynx General features: – Chondroblasts—cartilage cells that produce the matrix – Chondrocytes—cartilage cells that are trapped in lacunae (cavities) – Perichondrium—sheath of dense irregular connective tissue that surrounds elastic and most hyaline cartilage (not articular cartilage) » Contains a reserve population of chondroblasts that contribute to cartilage growth throughout life 61  Cartilage 2 General features of cartilage (continued): No blood capillaries (avascular) Diffusion brings nutrients and removes wastes Heals slowly Types of cartilage vary with fiber composition Hyaline cartilage Fibrocartilage Elastic cartilage 62  Hyaline Cartilage a: ©Ed Figure Reschke/Stone/Getty Images 5.19 – Clear, glassy appearance because of fineness of collagen fibers – Eases joint movement, holds airway open, moves vocal cords, growth of juvenile long bones – Locations: articular cartilage, costal cartilage, trachea, larynx, fetal skeleton Access the text alternative for slide images. 63  Elastic Cartilage a: ©Ed Figure Reschke/Stone/Getty Images 5.20 – Cartilage containing abundance of elastic fibers – Covered with perichondrium – Provides flexible, elastic support – Locations: external ear and epiglottis Access the text alternative for slide images. 64  Fibrocartilage a: Dr. Figure Alvin Telser 5.21 – Cartilage containing large, coarse bundles of collagen fibers – Resists compression and absorbs shock – Locations: pubic symphysis, menisci, Access the text alternative images. for slide and intervertebral discs 65  5.3e Bone 1 Bone (osseous tissue) is a calcified connective tissue that composes the skeleton Two forms of osseous tissue: – Spongy bone—delicate slivers and plates give it a spongy appearance Found in heads of long bones and in middle of flat bones such as the sternum – Compact (dense) bone—denser calcified tissue with no visible spaces Forms external surfaces of all bones 66  Bone 2 Features of compact bone: Arranged in cylinders called osteons – Central (osteonic) canal—passage running longitudinally along bone shaft; contains blood vessels and nerves – Concentric lamellae—ringlike layers of bone surrounding central canal – Osteon—central canal and its surrounding lamellae – Osteocytes—mature bone cells within lacunae between lamellae – Canaliculi—delicate canals radiating from each lacuna to its neighbors, allowing osteocytes to contact each other Periosteum—tough fibrous connective tissue covering the whole bone 67 Supporting Connective Tissues: Bone Figure 3.18 Bone  Compact Bone a: Dennis Figure Strete/McGraw-Hill 5.22 Cylinders that surround central (osteonic) canals that run longitudinally through shafts of long bones – Blood vessels and nerves travel through central canal Bone matrix deposited in concentric lamellae Access the text alternative for slide images. 69  5.3f Blood Blood—fluid connective tissue that travels through tubular blood vessels Transports cells and dissolved matter from place to place – Contains formed elements suspended in a liquid ground substance called blood plasma – Formed elements include: Erythrocytes (red blood cells, RBCs)—transport O2 and CO2 Leukocytes (white blood cells, WBCs)—defend against infection and disease » Examples: neutrophils, eosinophils, basophils, lymphocytes, monocytes Platelets—cell fragments involved in clotting 70  Blood Smear a: ©Ed Reschke/Stone/Getty Figure Images 5.23 Erythrocytes appear as pale pink discs with light centers Leukocytes are slightly larger and have variously shaped nuclei Platelets are small cell fragments with no nuclei Access the text alternative for slide images. 71  Nervous and Muscular Tissues: Introduction Excitability—ability to respond to stimuli by changing membrane potential – Developed to highest degree in nervous and muscular tissues, so they are called excitable tissues Excitation founded in charge difference (voltage) across membrane called the membrane potential In nerve cells, changes in voltage result in rapid transmission of signals to other cells In muscle cells, changes in voltage result in contraction, shortening of the cell 72  5.4a Nervous Tissue Nervous tissue—specialized for communication by electrical and chemical signals – Consists of: Neurons (nerve cells) detect stimuli, respond quickly, and transmit coded information rapidly to other cells Neuroglia (glial cells) protect and assist neurons, are the “housekeepers” of nervous system – Parts of a neuron: Cell body—houses nucleus and other organelles; controls protein synthesis Dendrites—short, branched processes that receive signals from other cells and transmit messages to the cell body Axon (nerve fiber)—sends outgoing signals to other cells; can be more than a meter long 73 Neuron and Glial Cells a: ©Ed Reschke/Stone/Getty Images Access the text alternative for slide images. Figure 5.24 74  5.4b Muscular Tissue Muscular tissue—specialized to contract when stimulated, exerting a physical force on other tissues, organs, or fluids Also an important source of body heat Three types: – Skeletal – Cardiac – Smooth 75  Skeletal Muscle a: ©Ed Reschke/Photolibrary/Stone/Getty Figure Images 5.25 – Made of muscle fibers—long thin cells – Most skeletal muscles attach to bone – Contains multiple nuclei adjacent to plasma membrane – Striations—alternating dark and light bands – Voluntary—conscious control over skeletal muscles Access the text alternative for slide images. 76  Cardiac Muscle a: ©Ed Reschke/Stone/Getty Images Figure 5.26 – Limited to the heart wall – Cardiomyocytes are short and branched with one centrally located nucleus – Intercalated discs join cardiomyocytes end to end – Striated and involuntary (not under conscious control) Access the text alternative for slide images. 77  Smooth Muscle a: Dennis Figure Strete/McGraw-Hill 5.27 – Made of short, fusiform-shaped cells – Cells have one central nucleus, no striations – Involuntary function – Most is visceral muscle—making up parts of walls of hollow organs Access the text alternative for slide images. 78 Courtesy Dennis Streete. Resources This Power Point presentation includes slides & content taken from Mac Graw Hill power point slides & some Elsevier slides. Anatomy and Physiology, Saladin 10th edition" by Kenneth S. Saladin, published by Mac Graw Hill, ISBN- 10-1266046674 Patton, K.T., & Thibodeau, G.A. (2020). Structure and function of the body (16th ed.). St. Louis, Missouri: Elsevier  Thank you +974 4495 2222 [email protected] Location University of Doha for Science & Technology 68 Al Tarfa, Duhail North P.O. Box 24449 Doha, Qatar udst.edu.qa