AnaPhy_Lecture-on-Tissues.pdf

HUMAN ANATOMY AND PHYSIOLOGY WITH PATHOPHYSIOLOGY Baltazar, J.N. [MLS 1-2] | ⋅˚₊‧ ଳ⋆.◌ೃ࿔*:･ Found in different areas such as body BASIC TYPES OF BODY TISSUE coverings (skin), body linings Epithelial...

HUMAN ANATOMY AND PHYSIOLOGY WITH PATHOPHYSIOLOGY Baltazar, J.N. [MLS 1-2] | ⋅˚₊‧ ଳ⋆.◌ೃ࿔*:･ Found in different areas such as body BASIC TYPES OF BODY TISSUE coverings (skin), body linings Epithelial Tissue (cardiovascular, digestive, and respiratory Connective Tissue Nervous Tissue systems), and glandular tissue (glands of Muscle Tissue the body) Its functions involve: TISSUE ® Protection ® Absorption – nutrient and water Groups of cells with similar structure and absorption function ® Filtration – seen in the kidneys; FOUR PRIMARY TYPES OF TISSUES: filters and regulates the exchange of materials ® Secretion (and Excretion) – form glands that produce & secrete various substances SPECIAL CHARACTERISTICS OF EPITHELIUM 1) CELLULARITY - Composed of closely packed cells with little extracellular 1) EPITHELIUM (epithelial) – serves as material between covering; acts as a protective barrier (ex: skin, 2) SPECIALIZED CONTACTS lining of intestine) - Adjacent epithelial cells are 2) CONNECTIVE – provides supports; binds bound together to form tissues together (ex: adipose tissue) continuous sheets by 3) NERVOUS – transmits electric signals all specialized contacts such as throughout the body (ex: neurons, glial cells) desmosomes (are formed to 4) MUSCLE – movement link between cells & provide connections between HISTOLOGY immediate filaments of the cell cytoskeleton) and tight Study of tissues junctions (a form of water that is tight-sealed and EPITHELIAL TISSUE prevents materials from passing between cells) 3) POLARITY - Exhibits polarity by having an apical surface and a lower attached basal surface - All epithelia exhibit polarity 4) SUPPORTED BY CONNECTIVE TISSUE Baltazar, J.N. | 1  -Supported by the underlying SHAPES OF CELLS connective tissue (reticular lamina) containing collagen SQUAMOUS fibers 5) INNERVATED BUT AVASCULAR - Nourished by substances diffusing from blood vessels in the underlying connective Flattened tissue Allow for diffusion and filtration 6) HAS A HIGH REGENERATION CAPACITY - Replace last cells rapidly by CUBOIDAL cell division - APICAL SURFACE BASAL SURFACE Cube-shaped Exposed to the side Attached to the Roughly equal in height and width that faces the body underlying Responsible for secretion and absorption surface connective tissue COLUMNAR NUMBER OF CELL LAYERS SIMPLE Column-like Tall & wide columns Often used for absorption and secretion (like cuboidal) and can be found in areas One layer where these processes are critical Typically involved in absorption, secretion, **Columnars are longer (sometimes wider) than and filtration cuboidal STRATIFIED SIMPLE EPITHELIUM Absorption, secretion, and filtration Single layer; usually very thin Protection is NOT one of their specialties Ex: alveoli in the lungs and lining of the blood vessels More than one layer Provides protection against mechanical and chemical stress Baltazar, J.N. | 2  SIMPLE SQUAMOUS PSEUDOSTRATIFIED COLUMNAR Single layer of flat cells Usually forms membranes Single layer, but some cells are shorter than Lines body cavities others Lines lungs and capillaries Often looks like a double cell layer Allows passage of materials by diffusion and 1) NON-CILIATED (male’s sperm-carrying filtration ducts and ducts of large glands) 2) CILIATED (line the trachea, most of the SIMPLE CUBOIDAL upper respiratory tract) STRATIFIED EPITHELIUM Contains two or more cell layers Main function is PROTECTION Regenerates from below: o The basal cells divide and push apically to replace the older surface cells Single layer of cube-like cells o Stratified squamous epithelium is Common in glands & their ducts composed of several layers Forms walls of kidney tubules & ducts o Transitional Epithelium Covers the ovaries Secretion and Absorption STRATIFIED SQUAMOUS SIMPLE COLUMNAR Single layer of tall cells Often includes goblet cells, which produce Thick membrane composed of several cell mucus layers (top-most layer is flat and scale-like) 1) NON-CILIATED (digestive tract, gallbladder, Surface cells are SQUAMOUS and basal cells etc.) are CUBOIDAL or COLUMNAR 2) CILIATED (small bronchi, uterine tubes, 1) KERATINIZED (epidermis of the skin; a dry regions of the uterus membrane) Absorption and secretion of mucus and 2) NON-KERATINIZED (moist linings of the enzymes esophagus, mouth, and vagina) Baltazar, J.N. | 3  Protects underlying tissues in areas subjected CHARACTERISTICS OF CONNECTIVE TISSUE to abrasion 1) COMMON ORIGIN - Originated from STRATIFIED CUBOIDAL mesenchyme 2) EXTRACELLULAR MATRIX - “ECM” - Non-living material that surrounds living cells - Most prominent feature of connective tissues - Composed of grouped Rare substances and fibers Generally, two layers of cells - Provides structural support Provides protection and contributes to secretion and mediates the exchange Mostly found in the ducts of some larger glands of materials between cells (sweat glands & mammary glands) and the environment TRANSITIONAL EMBRYONIC Resemble both stratified squamous and Gel-like ground substance containing FIBERS stratified cuboidal (star-shaped mesenchymal cells) Surface cells are DOME-SHAPED or Primarily in embryo SQUAMOUS-LIKE and basal cells are Gives rise to all other connective tissue CUBOIDAL or COLUMNAR Lines the ureters, bladders, and part of the THREE MAIN STRUCTURAL urethra ELEMENTS OF CONNECTIVE TISSUE Stretches readily and permits distension 1) Ground Substance – Extracellular CONNECTIVE TISSUE Matrix 2) Fibers – Extracellular Matrix; Found everywhere in the body classified into the following: Includes the most abundant and widely Collagen (strong, flexible) distributed primary tissues Elastic (allows tissue to Its functions involve: stretch) ® Binds body tissues together Reticular (thin-branching, forms support networks) ® Supports the body ® Provides protection 3) Cells Baltazar, J.N. | 4  LCT: ADIPOSE FOUR MAIN CLASSES OF CONNECTIVE TISSUE 1) CONNECTIVE TISSUE PROPER Loose CT Dense CT Areolar Dense Regular Adipose Dense Irregular Reticular Elastic Matrix as in areolar but very sparse Closely packed adipocytes (fat cells) Nucleus pushed to the side by the large fat 2) CARTILAGE droplet Hyaline Provides reserve food fuel Elastic Insulates against heat loss Fibrocartilage Supports and protects organs 3) BONE TISSUE Under skin, kidneys, and eyeballs Compact Within abdomen Spongy Breasts 4) BLOOD WBCs LCT: RETICULAR RBCs Platelets LCT: AREOLAR Network of reticular fibers in a typical loose ground substance Fibers form internal skeleton (stroma) that supports other cell types (WBC, mast cells, Gel-like matrix with all three fiber types, and macrophages) fibroblasts, microphages, mast cells, and Lymphoid organs some white blood cells Wraps and cushions organs DENSE CONNECTIVE TISSUE Its macrophages phagocytize bacteria Important role in inflammation One of the two subclasses of connective Holds and conveys tissue fluid tissue proper: Widely distributed under epithelia of the Dense Regular Connective Tissue body contains closely packed bundles of collagen fibers running in the same direction and makes up and tendons and ligaments Dense Irregular Connective Tissue contains thick bundles of collagen fibers Baltazar, J.N. | 5  arranged in an irregular fashion and is found in the dermis DCT: ELASTIC DCT: REGULAR Composed of collagen and elastin fibers Capable of stretching and recoiling with Primarily parallel collagen fibers strength in the direction of the fiber orientation Few elastic fibers Dorsal aspect of the neck, vocal cords, and Fibroblast: major cell type blood vessel walls Attaches muscle to bones or to muscles Attaches bone to bones CARTILAGE Withstand great tensile stress when pulling force is applied Stands up to both tension (stretching) and Tendons, most ligaments, aponeuroses compression Ground substance varies from a fluid to a DCT: IRREGULAR viscous gel Matrix contains an exceptional amount of tissue fluid (up to 80% water) Movement of tissue fluid in its matrix enables the cartilage to rebound after being compressed and also helps to nourish the cartilage cells THREE VARIETIES OF CARTILAGE: 1) HYALINE (gristle) Primarily irregularly arranged collagen fibers - Provides smooth surfaces for Provides strength and resists tension from movement multiple directions - Most abundant cartilage Some elastic fibers - CHONDROBLASTS produce the Fibroblast: major cell type matrix Able to withstand tension exerted in many - CHONDROCYTES lie in lacunae direction - Supports and reinforces Provides structural strength - Has resilient cushioning properties Dermis of the skin - Resists comprehensive stress Submucosa of digestive tract - Forms most of the embryonic Fibrous capsule of organs and of joints skeleton - Covers the ends of long bones in joint cavities - Forms costal cartilage of the ribs - Cartilage of the nose - Trachea and larynx Baltazar, J.N. | 6  2) ELASTIC Reside in the lacunae (cavity in bone or - Contains elastic fibers and provides cartilage) within the matrix they have made greater flexibility - Most abundant cartilage but more BLOOD elastic fibers in matrix - Provides elasticity - Maintains the shape of a structure while allowing great flexibility - External ear (pinna) - Epiglottis 3) FIBROCARTILAGE - Provides strong support and Fluid within blood vessels resisting compressions Can be RED or WHITE blood cells - Matrix similar to but less firm Most atypical connective tissue - Thick collagen fibers predominate Does not connect things or give support - Tensile strength with the ability to Classified as connective tissue because it absorb compressive shock develops from mesenchyme and consists of - Intervertebral discs, pubic blood cells, surrounded by a nonliving fluid symphysis, discs of knee join matrix called BLOOD PLASMA Transports nutrients, gases, waste products BONE Circulates all throughout the blood vessels Osseus Tissue Has an exceptional ability to support and NERVOUS TISSUE protect body structures due to its hardness, which is determined by the additional collagen fibers and calcium salts found in the extracellular matrix MATRIX is similar to that of cartilage but is harder and more rigid because, in addition to its more abundant collagen fibers, bone has an added matrix element – inorganic calcium salts (bone salts) Main component of the nervous system which Site for cell formation (HEMATOPOEISIS) regulates and controls body functions Have neurons as branching cells Cell processes that may be quite long extend from the nucleus containing cell body Composed of two types: 1) NEURONS – specialized cells that generate and conduct electrical impulses 2) SUPPORTING CELLS – nonconductive cells that support, insulate, and protect the BONE: OSTEOBLASTS neurons Transmits electrical signals from sensory Immature bone cells receptors and to effectors (muscles and glands) BONE: OSTEOCYTES Brain, spinal cord, nerve Mature bone cells Baltazar, J.N. | 7  MUSCLE TISSUE SMOOTH MUSCLE Crucial for contractions and movement Highly cellular, well-vascularized tissues Muscle cells (muscle fibers) possess MYOFILAMENTS which are elaborate versions of the actin and myosin filaments that bring out movement or contraction in all muscle cell types Has 3 types: Spindle-shaped cells with central nuclei 1) Skeletal No striations 2) Cardiac Cells arranged closely to form sheets 3) Smooth Propels substances or objects along internal passageways SKELETAL MUSCLE Involuntary controls Mostly in the walls of hollow organ REGENERATION OF TISSUE Tissues that regenerate easily [Epithelial Tissue, Fibrous connective tissues and bone] Long, cylindrical, multinucleate cells, Tissues that regenerate poorly obvious striations [Skeletal muscle, cartilage] Transmit electrical signals from sensory Tissues that are replaced largely with scar tissue receptors and to effectors [Cardiac muscle, nervous tissue within the brain Voluntary movement and spinal cord] Locomotion Facial Expression In skeletal muscles attached to bones and occasionally to skin CARDIAC MUSCLE Branching, striated, generally uninucleate cells that interdigitate at specialized junctions (intercalated discs) As it contracts, it propels blood into the circulation Involuntary control Walls of the heart Baltazar, J.N. | 8