TISSUES.pdf

ANAPHY: ANATOMY AND PHYSIOLOGY TOPIC: Tissue Level of Organization 1st Semester / BSN 1-Y1-33: Prelims Transes By: Shann Mikaela J. Serrano TISSUES...

ANAPHY: ANATOMY AND PHYSIOLOGY TOPIC: Tissue Level of Organization 1st Semester / BSN 1-Y1-33: Prelims Transes By: Shann Mikaela J. Serrano TISSUES - Tissues must be carefully prepared for examination - Multiple factors influence the appearance of a tissu - Are group of cells that function together in the body Stained used during preparation - A group of cells that performs a specific function CUTTING TISSUES FOR EAMINATION - Four main types of tissue make up the human body. - special blade is used to cut tissues Cut into thin slides for examination Histology - Microscopic study of the appearance, function, and TISSUES PLACED ON SLIDES organization of tissues. - thin slices of tissue are placed on slides - Is the study of tissue structure, organization and function. TISSUES ARE STAINED FOR EXAMINATION Pathology - many tissues are stained prior to examination - Study of changes that occur with disease - Study of changes associated with disease of tissues. RESULTS OF VARIOUS STAINS - tissues may have different appearances and colors depending on TISSUE TYPES the stain used. - The four types of tissue in the body are: EPITHELIAL TISSUES 1. EPITHELIAL TISSUE - Form, coverings, linings, and glands CHARACTERISTICS OF EPITHELIA 2. CONNECTIVE TISSUE - Protection and support - form coverings, linings 3. MUSCLE TISSUE - basement membrane anchors epithelia to ECM - Provides movement Two Surfaces of Epithelia: 4. NERVOUS TISSUE Basal Surface – attached to basement membrane - Allows communication Apical Surface – exposed to external environment or internal environment GENERAL FEATURES OF TISSUES - Avascular - Highly regenerative EXTRACELLULAR MATRIX (ECM) – material found outside of a tissue ANATOMY OF EPITHELIA Major Components: - Epithelia are: - Collagen – tough, protective proteins fibers - Proteoglycans - negatively charged protein, Highly cellular carbohydrate molecules Polar (apical and basal surface) Avascular Cellular Connections – attachments between cells Innervated Tight Junctions – allow no movement of substances Bound to basement membrane between cells Desmosomes – flexible connections that allow some THE EPITHELIAL CELL movement of substances between cells Gap Junctions – passageways that allow movement - Apical and basal membranes may have different functions of certain substances between the cells - Apical surface modifications Cilia – move materials across surface CELLULAR CONNECTIONS Microvilli – increase surface area - cells can be connected by; CELLS OF EPITHELIA Tight Junctions – fuse membranes of adjacent cells Desmosomes – provide strong, flexible connections - Epithelial tissue is named after its shape and number of layers of between cells cells on the apical surface. - Based on Shape: Hemidesmosomes connect cells to ECM Squamous – flat cells Gap Junctions – allows for intercellular passageways between cells Cuboidal – box-shaped cells Columnar – column-like cells TISSUES FOR EXAMINATION - Based on number of layers; Simple – one layer of cells PREPARING TISSUES FOR EXAMINATION Stratified – two or more layers of cells  GLANDS OF EPITHELIA Pseudostratified – one layer of cells that appears like more - Endocrine glands secrete hormones into the blood - are ductless EPITHELIA THAT DEFY NAMING CONVENTION Example: thymus, pituitary gland, adrenal glands - Exocrine glands secrete substances locally through a duct PSEUDOSTRATIFIED COLUMNAR EPITHELIUM - secrete mucus, sweat, saliva, and breastmilk - May appear stratified Example: sweat glands and glands of digestive system - All cells touch basement membrane because there is only a - single layer EXOCRINE GLAND STRUCTURE TRANSITIONAL EPITHELIUM - Tubular glands form tube s - stratified tissue - acinar glands form pockets - cells stretch and change shape - simple glands have one duct - compound glands combine formats GOBLET CELLS EXOCRINE SECRETIONS - Common feature of simple and pseudostratified epithelia - secretes mucus MEXCRINE SECRETION: accomplished by exocytosis APOCRINE SECRETION: material accumulates near apical surface of the gland STRATIFIED EPITHELIA HOLOCRINE SECRETION: involves rupture and destruction of - contain more than one layer of cells entire gland cell - Cells of basal layer are stem cells that regenerate cells into apical layers - basal layers cells may be different in shape from apical layer cells CONNECTIVE TISSUE - Tissue is named based on shape cells in apical layer ANATOMY OF CONNECTIVE TISSUE SIMPLE SQUAMOUS EPITHELIUM - connective tissue consists of cells and the extracellular matrix - consists of a single layer of flat cells (ECM) - found in the air sacs of lungs, the lining of the heart, blood vessels, - cells rarely touch each other and lymphatic vessels. - ECM consists of ground substances and fibers - Allows materials to pass through by diffusion and filtration - ground substances is between fibers - secretes lubricating substances - vascularized SIMPLE CUBOIDAL, SIMPLE COLUMNAR, PSEUDOSTRATIFIED CLASSIFICATION OF CONNECTIVE TISSUE COLUMNAR EPITHELIA - Twelve types of connective tissue are separated into three SIMPLE CUBOIDAL EPITHELIUM categories: - lines kidney tubules CONNECTIVE TISSUE PROPER - secretes and absorbs substances (Na+, K+, glucose, etc.) - Areolar, adipose, reticular, dense regular, and dense irregular connective tissue SIMPLE COLUMNAR EPITHELIUM SUPPORTIVE CONNECTIVE TISSUE - lines digestive and reproductive tracts - Hyaline cartilage, fibrocartilage. Elastic - secretes and absorbs various materials cartilage, compact bone, spongy bone FLUID CONNECTIVE TISSUE PSEUDOSTRATIFIED COLUMNAR EPITHELIUM - blood and lymph - lines trachea and respiratory tract - secretes and moves mucus CELLS AND FIBERS OF CONNECTIVE TISSUES STRATIFIED AQUAMOUS, STRATIFIED CUBOIDAL, AND STRATIFIED Fibroblasts produce fibers in the ECM COLUMNAR EPITHELIA Collagen – strongest fiber Elastic – provide elasticity STRATIFIED SQUAMOUS EPITHELIUM Reticular – branching fibers that support internal Organs - lines esophagus, mouth, vagina Adipocytes – store energy and provide cushioning - protects against abrasion WBC – provide immune function Red Blood Cells – carry gases such as oxygen and carbon dioxide STARTIFIED CUBOIDAL EPITHELIUM - found in sweat glands, salivary glands CONNECTIVE TISSUE TYPES - secretes and protects CONNECTIVE TISSUE PROPER STRATIFIED COLUMNAR EPITHELIUM Loose Connective Tissue - found in male urethra - Areolar - secretes and protects - Reticular SIMPLE SQUAMOUS EPITHELIUM SUPPORTIVE CONNECTIVE TISSUE - Lines bladder, urethra, and ureters Hyaline Cartilage - allows urinary organs to expand and stretch - located within joints, ribs - most abundant cartilage  Fibrocartilage Contains Striations – alternating light and dark - located din intervertebral discs bands under light microscope - strongest cartilage - voluntarily controlled Elastic Cartilage Involuntary Muscle – unconscious control - located in external ear Cardiac Muscle - most flexible type or cartilage - Found within internal organs - associated with digestive, respiratory, urinary, FLUID CONNECTIVE TISSUE and reproductive systems Blood and lymph - lack striations - transport molecules and cells throughout the body - involuntary controlled - blood contains cells: Erythrocytes, leukocytes, and platelets NERVOUS TISSUE - lymph is primarily acellular - lymph is a fluid connective tissue - unlike blood, lymph is mainly acellular ANATOMY OF NERVOUS TISSUE LOOSE CONNECTIVE TISSUES - nervous tissue make sup the brain, spinal cord, and peripheral nerves AREOLAR CONNECTIVE TISSUE - neurons conduct action potentials to communicate with other cells Subcutaneous layer - Glial cells support neural functioning Supports nearby tissues NEURONS AND NERVOUS TISSUE ADIPOSE TISSUE Subcutaneous layer - Neurons generate action potentials Energy, store, cushioning Anatomical Structure of Neurons: RETICULAR CONNECTIVE TISSUE Dendrites – short branches that receive signals Framework of internal organs Cell body – houses nucleus and organelles Lymphatic tissues, spleen, liver Axon – long projection used to send action potentials - Synapses is a gap between neuron and its target cell DENSE CONNECTIVE TISSUES GLIAL CELLS DENSE REGULAR CONNECTIVE TISSUE - there are various types of glial cells associated with nervous tissue Tendons, ligaments - many perform support functions for neurons DENSE IRREGULAR CONNECTIVE TISSUE - some form myelin that insulates axons Skin Allows for faster movement of action potentials Application: The Ribcage - The ribcage merges two supporting connective tissue MEMBRANES - bone makes up most of the ribcage - protects lungs and heart TISSUE MEMBRANES - cartilage allows for expansion during breathing BONE MUCOUS MEMBRANE - Mucous membranes line body cavities that are open to the - the most rigid of the connective tissues outside - provides protection and support internal organs - Line body cavities that are exposed to the external Compact Bone: - solid with greater strength than spongy bone environment Spongy Bone - Usually contain goblet cells that secrete mucus Associated with: - empty spaces contain red bone marrow 1. Digestive tract 2. Respiratory tract MUSCLE TISSUE 3. Urinary tract 4. Reproductive tract ANATOMY OF MUSCLE TISSUE SEROUS MEMBRANES - Muscle tissue is responsible for movement - Serous membranes line body cavities and surrounds some organs - cells are tightly packed - Cover and line internal organs - differs in location and manner of control - Reduce friction created as organs move - skeletal muscle, cardiac muscle, smooth muscle Examples include: Characteristics of Muscle Tissue: Pericardium of the heart - the major function of muscle is movement Pleura of the lungs Voluntary Muscle – conscious control Peritoneum of the abdominal cavity Skeletal muscle - attached to bone CUTANEOUS MEMBRANE - allows body movement and maintains posture - Cutaneous membrane is the skin and covers the body - Essentially the skin  - Protects body from desiccation and pathogens - Made of stratified squamous epithelium and connective tissue - Keratin provides a thick barrier for protection against pathogens SYNOVIAL MEMBRANE - Synovial membranes line joints - Found inside freely moveable joints like the elbow, hip, and knee - Cells secrete synovial fluid - Helps lubricate and nourish the cartilage at the joint - Reduces friction as bones move TISSUES GROWTH AND HEALING INFLAMMATION - The body’s initial response to injury - Limits extent of injury and begins the repair process - Acute inflammation is short-term - Chronic inflammation persists for long periods of time TISSUE HEALING - Begins with removal of debris and toxins - Clotting stops the bleeding - Granulation tissue forms to allow epithelial cells to regenerate lost tissue - Scar tissue may form due to rapid repair and replacement of collagen fibers TISSUE AND AGING - Tissue changes as the body ages - Rate of mitosis slows down Leads to slower tissue healing - Number of elastic fibers decreases Structures are less elastic Contributes to wrinkles, joint stiffness, and high blood pressure TISSUE AND CANCER - Mutation may alter the regulatory signals cell receives - Altered signals lead to uncontrolled replication of cells - Mass of cells is a tumor Malignant tumor – cancerous, cause diseases, and can spread to other areas of the body Benign tumor – do not cause disease in the body or metastasize (spread to other areas of the body)