Chapter 4: Tissue - Student Notes PDF

Chapter 4: Tissue: The Living Fabric Introduction Unicellular (one-cell) organisms I - Operates independently...

Chapter 4: Tissue: The Living Fabric Introduction Unicellular (one-cell) organisms I - Operates independently Multicellular human body - Form cell communities that work together 2 Tissues - Cell groups that work together - Similar structure and function 3 Four primary tissue types 1. Nervous tissue 2. Muscle 4 3. Epithelial 4. Connective 4.1 Tissue samples are fixed, sliced, and stained for microscopy TEM List the steps involved in preparing animal tissue for microscopic viewing. Preserved Sliced Stained Light microscopy Colored synthetic dyes used to stain tissue. charged molecules bind within tissues. ⑦G ______________ Variations in cellular uptake of dyes. Transmission electron microscopy (TEM) - stained with heavy metal salts - color is a property of light, not of electron waves. - artificially colored Scanning electron microscopy (SEM), - three-dimensional - unsectioned tissue surface TEM SEM - artificially colored cilia 4.2 Epithelial tissue covers body surfaces, lines cavities, and forms glands. List several structural and functional characteristics of epithelial tissue. Covering Stratified squamous of epidermis ↳ Keratinized Epithelium - sheet of cells o covers a body surface o lines a body cavity Two forms occur in the body 1. Covering and lining of epithelium Covering - outer layer of skin - closed ventral body cavity o walls and organs Lining - open cavities of respiratory, digestive, and urogenital systems Lining of digestive system (stomach) Glandular epithelium of Thyroid Gland 2. Glandular epithelium - Glands Functions - protection - absorb and secrete - filtration and excretion - sensory reception Y Special Characteristics of Epithelium A. Polarity Apical surface Basal surface B. Supported by Connective Tissue Basement membrane Location - Between __________________ epithelium and _______________________ connective tissues Function - Defines epithelial boundary Apical - Resists stretching and tearing Layers of basement membrane 1. Basal lamina O - Noncellular, adhesive supporting sheet G - __________________ Glycoproteins and collagen fibers 2. Reticular lamina - layer of extracellular material. - network of collagen fibers + reticular Fibers Basal C. Regeneration Basal Why necessary? lamina Basement membrane. - Exposure to friction and hostile substances Reticular lamina D. Specialized Contacts - Tight junctions and desmosomes E. Avascular but innervated - No blood vessels - Contains nerve fibers 2 Classification of Epithelial Tissue Name, classify, and describe the various types of epithelia, and indicate their chief function(s) and location(s). Name Function Layer(s)/Shape Apical Simple Epithelia I Diffusion, absorption, secretin, and filtration I I Basal Stratified Epithelia 2 protection 2t Apical Squamous A Flattened and scale like 2 Cuboidal Boxlike B Columnar Tall and column shaped C Basal A B C simple squamous Function Diffusion and filtration Location Lungs * Alveoli > - gas exchange Kidney 2) Glomeuli- solutes (filtration) Simple cuboidal Function Absorption and secretion Location Kidney tubules ⑧ - solutes Glands - secretion (exocrine + endocrine) Simple columnar Function Absorption and secretion microvill ; Location Feature Function -D (sur face Area) Small intestine Microvilli ↑ SA-absorption Goblet cell Intestine and Goblet cells Secrete mucous (mucous) respiratory tract - trap substances Uterine tubes Cilia propulsion 3  pseudostratifiedColumnar Goblet Location Feature Function all Trachea Goblet Secrete mucous cells cilia Trachea propulsion cilia Stratified Squamous Location Feature Function Skin (Epidermis) Abrasion resistant Keratinized Mouth non- Abrasion resistant Esophagus Vagina Keratinized Transitional Function Stretch Location Ureters and urinary bladder Two simple squamous epithelia in the body have special names that reflect their location. Endothelium Function - Friction slick, _________________ -reducing lining Location - Cardiovascular System o All hollow organs o Capillaries exclusively endothelium - - Lymphatic System o Lymphatic vessels Mesothelium Endothelium - Serous membrane 4  Exocrine Endocrine Exocrine and Endocrine gland development lose duct duct Endocrine cells Exocrine gland cells Unicellular Exocrine glands: Goblet cell Glandular Epithelia microvilli Define gland. Differentiate between exocrine and endocrine glands and between multicellular and unicellular glands. Describe how multicellular exocrine glands are classified structurally and functionally. mucin Gland - Cells that produce a secretion Endocrine glands Golgi - “Internally secreting” - Ductless glands > capillaries - Rough ER - Produce hormones Exocrine glands - Secretions to body surface or into body cavities Includes Liver Bile - Multicellular Exocrine glands: Structural classification Pancreas & Digestive enzymes Salivary glands Simple ducts compound ducts Sweat and oil glands Many others Unicellular exocrine glands Tubular 8 - - One celled: Mucous and Goblet cells Location: Intestinal and Respiratory tracts L "Simple - Mucin production tubular compound ↑ tubular Multicellular exocrine glands Two basic parts 1. Epithelium-derived duct 2. Secretory unit Alveolar secretory G Structural classification structure 1. Ducts simple alveolar compound - Based on duct structure alveolar tubuloalveolar Simple glands: ___________________ unbranched duct Compound glands: ___________________ branched duct Multicellular Exocrine Glands: Modes of secretion 2. Secretory units (acinus) Tubular: secretory cells form _______________ tubes Alveolar: secretory cells form _______________. flask-like sacs Tubuloalveolar: have both types of secretory units. Modes of secretion product - Merocrine exocytosis J - released - Holocrine - cell ruptures merocrine holocrive 5  4.3 Connective tissue is the most abundant and widely distributed tissue in the body. Indicate common characteristics of connective tissue, and list and describe its structural elements. Describe the types of connective tissue found in the body and indicate their characteristic functions. Four main classes of connective tissue and several subclasses 1. Connective tissue proper - loose v dense. 2. Cartilage 3. Bone 4. Blood Common Characteristics of Connective Tissue Extracellular matrix Extracellular matrix Feature: separates the living cells of the tissue. GroundSubstance Function Fiber - bears weight and withstand tension collagena Reticular - endure abuses and physical trauma - abrasion Common origin: all connective tissue arises from ______________ mesenchyme Composed of Ground substance and fibers Structural Components of Connective Tissue Connective tissues have three main components - ground substance, fibers, and cells. _____________________________= Extracellular matrix ground substance and fibers 1. Ground Substance - unstructured material - fills the space between the cells and contains fibers. Extracellular matrix a. Interstitial fluid Features - large amounts of fluid Function - nutrient and solute _________ diffusion between capillaries and cells. - Fibers o reduce pliability o minimally ___________ hinder diffusion. b. Cell adhesion proteins Extracell a Function - connective tissue glue c. Proteoglycans - Glycosaminoglycans (GAGs) o chondroitin sulfate o hyaluronic acid - form aggregates o GAGs intertwine and _________ trap water - substance varies à fluid to a viscous gel o ­GAGs = ________ ↑ viscosity of the ground substance. - marixed cell adhesion proteins "Sticky" > - Proteoglycans - Entrcellular ↓ Meagan sobstne+ Fibers Extracellular floid erstitial Pluid = 6 ↳ nutrient + solute exchange (diffusion) 2. Connective Tissue Fibers a. Collagen Fibers Feature - Most abundant collagen Composition - thick Fibrous protein collagen forms ________________ collagen fibers Function - high tensile strength to the matrix. Location - Collagen secreted into the extracellular space > ligaments - tendons b. Elastic Fibers Feature - Form branching networks in the extracellular matrix. Composition - Contain a rubberlike protein, ______________________. elastin Function - Stretch and recoil Location - skin, lungs, and blood vessel walls. c. Reticular Fibers Feature - Short, fine fibers Composition - thinner Different type of collagen à _______________ collagen fibers. Function - Extensive branching à forms delicate _________________ network o surround small blood vessels o support the soft tissue of organs Location - Spleen, lymph nodes, bone marrow, kidney ↳ lymphoid organs 3. Connective tissue cells Resident cell types in connective tissue - immature (-blast) - mature (-cyte) Examples Connective tissue proper: Fibro ________ blasts à cytes Cartilage: chondro ___________ blast à cytes Bone: ______________ Osteo blasts à cytes J collagen Other cell types Fat cells: adipocytes White blood cells: leukocytes Mast cells - initiate local inflammatory response against microbes. - secretory granules with chemicals o Heparin anti-coagulant - o Histamine "Yeaky" capillaries - Macrophages Function - phagocytes Location - loose connective tissue, bone marrow, and lymphoid tissue. - Fixed or migratory 7 Types of Connective Tissue All mature connective tissues except for bone, cartilage, and blood are __________________________. Connective +issue proper Areolar ConnecRve Rssue proper subclasses Adipose Loose proper v. Dense proper Reticular Both types of connec[ve [ssue contain Regular - fibers and ground substance irregular elastic Subtypes Ground substance Fibers elastic Loose proper ↑ Hyaline ↓ Fibrocartilage Dense proper ↓ ↑ Loose-Connective Tissue proper subtypes Areolar Function Packs organs à wrap and cushion - Fibroblasts Immunity Elastic - Macrophages ~L Fibroblasts - Inflammation Location - Widely distributed - > lamina collagen propria Adipose Function - Insulation nuclei - Support and protect ~ - Fuel reserve triglycerides - Location - Hypodermis - Breasts - Abdomen - Eyes and kidneys Cells Adipocytes Reticular Function - Immunity - Stroma reticular - Location Oleukocyte J immunity - Spleen - Lymph nodes - Bone marrow Cells Leukocytes - > spleen > Filters - blood. 8 Dense – Connective tissue proper subtypes Dense regular Function Withstand __________ uni- directional tension Location Ligaments Tendons Cells Fibroblasts Dense irregular Function Withstand _______________ multi- directional tension Location Fibrous capsule of joints Dermis of skin -collagen Fibers Cells Fibroblasts ↳ Fibrous capsule Elastic Function Recoil Location - Elastic Aorta Fibers. 9 Cartilage Features of CarRlage - Lacks nerve fibers - Avascular - Receives nutrients via diffusion o perichondrium Ground substance - 80% water - contains GAGs and collagen fibers Cells - Chondroblasts à Chondrocytes o lacunae Hyaline CarRlage Significance - Most abundant car[lage Appearance Femr - lacuna e (Chondro- - Glassy (has collagen) Loca?on line cytes) - Ends of long bones PO - - Costal car[lage Respiratory structures /7 tibia o Nose o Trachea > - costal o larynx Cartilage Fibrocartilage Function - Absorb compressive forces Location - Meniscus - Intervertebral discs lawnae 000 - - Pubic symphysis > chondrocytes Elastic Cartilage - > more elastic fibers than hyaline cartilage. Function - Maintain shape and flexibility Location - Ears - Epiglottis 10  am &a i Bone Function - - - Support and protect Levers Calcium storage Location - Bones Features - Highly vascularized symphocyte Blood Function - -RBCS - Transport o Nutrients and wastes o Respiratory gases neutrophil o Ions o Leukocytes Location - Within blood vessels 4.4 Muscle tissue is responsible for body movement Compare and contrast the structures and body locations of the three types of muscle tissue. Muscle Type Structures Body Locations Functions Skeletal Muscle Long and cylindrical Attached to bones or ________________ voluntary movement and Striations occasionally to skin control ____________nucleate multi Skeletal Cardiac Muscle Branching Walls of the heart _________________ involuntary control Striations Blood propulsion Uninucleate cardiac Smooth Muscle Spindle shaped Walls of hollow organs Propel substances along internal _______ No striations passageways > GI tract - Uninucleate (central) blood vessels Smooth ↳ Arteries intercalated discs 11 4.5 Nervous Tissue is a specialized tissue of the nervous system. Indicate the general characteristics of nervous tissue. Nervous tissue cell nuclei Function Neuron processes body - Respond to stimuli Axon - Transmit electrical impulses over substantial distances within the body cell body Location - Brain Neuron processes - Spinal cord - Nerves 4.6 The cutaneous membrane is dry; mucous and serous membrane are wet. Describe the structure and function of cutaneous, mucous, and serous membranes. Body’s covering and lining membranes. Type of membrane Structure Function Cutaneous Skin; ____________________ Keratinized stratified squamous (epidermis) Protection from outside stimuli - attached to dermis Mucous Line all body cavities __________ open to the outside of the body Adapted for absorption and secretion - hollow organs of digestive, respiratory, and urogenital tracts. stratified squamous or simple columnar Serous closed Membranes found in ______________ ventral body cavities. _______________ lobrication for facing surfaces - consists of simple squamous epithelium > mesothelium - - thin layer of areolar connective tissue o mesothelial cells add slippery molecule hyaluronic acid. enclothelium - review Cutaneous Mucous pleura peritoneum 12  4.7 Tissue repair involves inflammation, organization, and regeneration Outline the process of tissue repair involved in normal healing of a superficial wound. Steps of Tissue Repair Repair occurs using same kind of tissue - Regeneration t replaced ↓ scar - Fibrosis J damaged tissue tissue Method used depends on - type of tissue damaged - severity of injury Example below platelets 1. InflammaRon Blood -> Q Clot - Trauma - Inflammatory chemicals o Leaky blood vessels o WBCs entry - Clotting o Prevents blood loss o Scab forms 2. Restore blood supply -leak - Organization o Granulation tissue inflammatory neutrophils capillaries ② chemicals - mitosis - Fibroblasts - Macrophages macrophages - Mitosis of epithelium Fibroblasts 3. Regeneration and Fibrosis budding Capillary - Margins get pulled together regenerated - Epithelium thickens and detaches epithelium - Scar tissue and epithelium regeneration ③ Fibrosed area Developmental aspect of tissue Primary germ layers include Ectoderm - Nervous tissue 16 old Mesoderm day embryo - Muscle and connective tissue mesoderm Endoderm - GI tract Epithelium from all three layers Ectoderm Endoderm 13