Basic Tissue PDF

Basic tissue: grp of cells with similar structure that work tgt to perform a specific func. 1st learning outcome: define basic tissues & their types The 4 main tissue types: 1. Epithelial tissue - Covers body surface, lines body cavities, forms glands 2. Con...

Basic tissue: grp of cells with similar structure that work tgt to perform a specific func. 1st learning outcome: define basic tissues & their types The 4 main tissue types: 1. Epithelial tissue - Covers body surface, lines body cavities, forms glands 2. Connective tissue - Supports the other basic tissue 3. Muscle tissue - Responsible for movements 4. Nervous tissues - Receives, transmits, integrates info to control activities of the body 2nd learning outcome: describe the classification of epithelium & their func. Characteristics of epithelial tissue: C- cellularity (lots of cells, no space between cells) R- rapid regeneration A-Avascular (meaning it lacks blood vessels, they rely on diffusion of nutrients & O2) P- polarity (apical sides faces free space- lumen; basal layer faces basement membrane) Func. : Protection Absorption Sensory reception Ion transport Secretion Filtration Formation of slippery surfaces (for movement) The classification of epithelial tissue is based on 2 main criteria: means it's 'square' A. The shape of the cells Squamous- wider than tall Cuboidal- as tall as wide Stall= widel Columnar- taller than wide B. Thickness of the cell layers Simple- 1 cell layer Stratified- more than 1 cell layer Pseudostratified- appear stratified [ for understanding only: Actlly it’s a single layer of cell, ‘pseudostratified’ means ‘falsely stratified’ where all the cells are in contact with the basement membrane but not all cells reach the surface]  The classification of the epithelium: the 8 cell types of epithelium layer 1 Cells 1. 1 Simple squamous wide than fall Description Location Func. A single layer of flattened cells Kidney glomeruli & Allw material to pass thru epithelium with disc-shaped central nuclei corpuscles (small by diffusion & filtration, & sparse cytoplasm cells), air sacs of lungs, secretes lubricating clittle) lining of heart, blood substances in serosae vessels, lymphatic vessels & lining of ventral body cavity (serosae) 2. Simple cuboidal epithelium A single layer of cube-like cells In ducts, secretory Secretion & absorption -thinkof rete a secretions with large, spherical central nuclei portions of small glands, kidney tubules, ovary surface 3. Simple columnar A single layer of tall cells with Non-ciliated type: Absorption, secretion of epithelium round/oval nuclei, some cells lines most of the digestive tract, mucus & enzymes, hv cilia, may contain mucus- gallbladder & excretory ducts of ciliated type propels secreting unicellular glands some glands (push) mucus by ciliary (goblet cells) Ciliated type: action Lines small bronchi, uterine tubes & some of uterus 4. Stratified squamous Thick membrane composed of Non-keratinised type: Protects underlying epithelium several cell layers, basal cells lining of oesophagus, tissues against abrasion (scrap are cuboidal/columnar & mouth & vagina Idead & tough metabolically active, surface Keratinised: epidermis cells are flattened of skin which is a dry In the keratinized type: surface membrane cells are full of keratin & dead, basal cells ative in mitosis, I producing cells of more superficial layers I thsa,meansSachedmoveupwardbeenare - in the 5. Stratified cuboidal 2 layers of cube-like cells Largest ducts of sweat Protection epithelium glands, mammary glands, salivary glands ISMS) 6. Stratified columnar Basal cells are cuboidal & Small amt in male Protection & secretion epithelium superficial cells (cells of the urethra & in large ducts outermost layer) are elongated of some glands & columnar 7. Transitional epithelium Resembles both stratified Lines the bladder, Capable of stretching & squamous & stratified ureters & part of permits distension cuboidal, basal cells cuboidal urethra (swelling/expansion) of or columnar, surface cells urinary organ due to dome-shaped or squamous- presence of urine like (dpn on degree of organ stretch)  ~diffusion & serosal ~secretion ~cicia-cliatedthetype ~Keratinizedener ② cuboidal epithelium ③ Simple columnar epithelium ④ Stratified squamous epithelium ① Simple squamous epithelium Simple disc shaped central nuclei - round central nuclei -round /oval central nuclei description: surface cells:flattened (squamous · - - · Simple:1 layer -func: secretion & absorption -func: absorption, secretion of - basal cells: cuboidal or columnar tall & cilia ↳ active Squamous: wider than -location: In ducts, secretory portion mucus, enzymes upwards · in mitosis, move to the surface cell, becomes keratinized diffusion & filtration propels Func: allws of small duct, kidney tubule mucus via ciliary action · keratinized type: Idead & tough of materials & secrete lubricating & surface ·description:cells hu gobletcell: unicellular gland epidermis of the skin ovary mucus secreting · location: forms the fluid in the serosae -cells hu cillia may -Non-keratinized type: of B. bud lymphatic vessels, location: type: Linesdigestisacanall lining ·Location: Non-ciliated location:lines mouth, oesophagus, vagina · lining ventral body cavity (serosae), -lines excretory ducts of some glands ·func: protects underlying tissue against air sacs of lung, kidney glomeruli, gallbladder abrasion - ciliated type: corpuscles -lines the bronchi - lines the uterus tube -lines of the uterus some region cilia & goblet all ⑥ stratified Cuba, epithelium ⑥ Stratified columnar ⑦ -urinary organ ~ epithelium Transitional epithelium ⑧ Pseudostratified columnar epithelium -description: layer (superficial layer outermost -resembles both stratified squamous & stratified cuboidal hu gobletcells cillia - - ↳ columnar - basal cell:cuboidal/columnar -func:secretion of mucus & -basal layer:cuboidal - outermost layer: squamous cilia propels mucus by Func:protection & secretion action -funciprotection func:stretches & allws distension of cillary - - -location:urethra ducts of some - location:SMS & large glands urinary organ by contained urine Location: - ciliated:lines the trachead upper respiratory tract - sweat glands -location:ureter, bladder, urethra -nonciliated:lines the male sperm -Salivary glands urinary carrying ducts & ducts Mammary glands - of large glands 8. Pseudostratified columnar Single layer of cells of diff Non-ciliated: Secrete mucus, epithelium heights, nuclei seen at diff lvls, In male’s sperm-carrying ducts & propulsion of mucus by may contain goblet cells & cilia ducts of large glands ciliary action Ciliated: Lines trachea, most of upper respiratory tract 3rd learning outcome: describe the glandular epithelium & classification Glandular epithelium - Specialised to produce & secrete substances Classification of glandular epithelium: Classification by secretion type 1. Exocrine glands: - Release secretion via a duct onto body surfaces (skin) - Composed of highly specialised epithelial cells: glandular epithelia 2. Endocrine glands: - ‘ductless gland’ secrete hormone (messenger molecules), carried by blood to target organs Classification by nature of secretion 1. Serous gland: watery secretion 2. Mucous gland: slimy. Chemically inert (stable) mucous secretion 3. Mixed: mixed discharge Classification by mechanism of secretion 1. Merocrine: cells remain intact Be 2. Apocrine: apical portion (outermost part) of the cells are detached, along with the secretion 3. Holocrine: entire cell is discharged during secretion Classification by shape of the terminal ends of 1. Tubular: elongated grp of secretory cells with tube-shaped lumen secretory units 2. Acinar/ Alveolar: small grapelike/ sac-like grp of secretory cells arranged ard a small lumen 3. Tubule alveolar: combination of 1 & 2 Classification by arrangement (branched or not) & 1. Simple glands: unbranched duct occurrence of duct system 2. Branched gland: several secretory units empty into an unbranched duct 3. Compound gland: secretory portions empty into a branched duct system, draining into larger ducts  4th learning outcome: describe the connective tissues proper & discuss their func. Connective tissues - Refers to a grp of tissues which originates from mesenchymal cells - Main func: provides structural support to the organs of the body Composition: Cells: - are cells that make up connective tissue, these cells are responsible for producing the components of the extracellular matrix Extracellular matrix: - connective tissue cells make proteins fibres & ground substances, releasing them into the intercellular space by exocytosis4. Once released by exocytosis, protein & ground substance forms the extracellular matrix [matrix: protein fibres + ground substance] ➔ R Protein fibres: collagen fibres, elastic fibres, reticular fibres ➔ Ground substance: proteoglycans, multi-adhesive glycoprotein & glycosaminoglycans Connective tissue proper cells: 1. Mesenchymal cell (undifferentiated stem cells in connective tissue that can develop into various cell types) 2. Fibroblast/fibrocyte - make protein fibres & ground substance 3. Macrophage 4. Leukocyte/ WBC 5. Plasma cell (produce antibodies) 6. Mast cells (release histamine) 7. Fat cells/ adipocyte - store energy in the form of fat 8. Pigment cell/ chromatophore (involved in coloration: skin pigmentation) Connective tissue fibres 1. Collagen- white fibres - Unbranched fibrils - Runs in wavy parallel courses - Provide tensile strength to tissues (resist tissue being stretched/ pull apart), flexibility & resistance 2. Elastic fibres- yellow fibres - Thinner than collagen fibres - Fibres branch & anastomose (cross-link), forming an irregular network - Can stretch to 1.5x of its length - Consist of protein elastin - Able to stretch & return to its original form 3. Reticular fibres - Extremely fine fibres - Short fibres branch & anastomose - Consist protein reticulin - Abundant in haemopoietic tissue- forms new blood cells - Forms supportive framework of soft tissue organs - Mainly found in lymphatic tissues -Paste pic from notion the connective tissue diagram And also paste the drawing of the connective tissue form notion -  Connective tissues: Embryonic connective tissues Adult connective tissues 1. Mesenchyme: - Connective tissue proper: loose & dense - differentiates to all other connective tissue types - specialised connective tissue: cartilage, bone, blood - location: primarily in embryo 2. Mucous (Wharton’s jelly) - (found in umbilical cord during fetal development) Adult connective tissues: connective tissue proper Loose connective tissue - Loose arrangement of protein fibres Types of loose Func. Description Location connective tissues 1. Areolar - Cushion organs, areolar tissue - Gel-like matrix - Under all epithelia tissue contains macrophage that containing of all 3 tissue of skin, phagocyte bacteria, essential fibres type: packages in inflammation, holds & fibroblast, (surrounds) organs coveys (transport) tissue fluid macrophages & & wall of blood mast cells vessels 2. Adipose - Reserve food fuels, insulates - It’s a modified - Under skin, ard tissue against heat loss, supports & areolar tissue, kidneys & eyeballs, protects organs matrix contains within abdomen & large nmb adipose in breast cells with fibrocytes & macrophages 3. Reticular - The reticular fibres forms - Network of reticular - Lymphoid organs tissue supportive framework fibres surrounded (lymph nodes, bone (stroma) that supports other by loose ground marrow & spleen) cell types (WBC, mast cells & substances macrophages) Dense connective tissue - Protein fibres are densely packed Types of dense connective Func. Description Location tissues 1. Dense irregular - Provides structural - Primarily collagen - Dermis of the strength, withstands fibres, some skin, submucosa tension exerted in many elastic fibres, of digestive tract, direction major cell type is fibrous capsules the fibroblast of organs & joints 2. Dense regular - Attaches muscle to - Primarily parallel - Tendons, most bones/ muscles to collagen fibres, ligaments, muscles/ bones to few elastic fibres, aponeuroses bones, withstand great major cell type is tensile stress when the fibroblast pulling force is applied in 1 direction  Specialized connective tissues (this table is only for understanding purpose) Chondrocytes secrete fine collagen Absorb compressive shock Provides shape & structural support with fibres, giving the matrix a smooth, glassy high degree of flexibility, can stretch & translucent look. Provides smooth return to ori shape surfaces for joint movement & support Paste pg33 bone 5th learning outcome: describe the types of muscle tissues 1. Skeletal muscle - Fibres: striated (having alternating dark & light bands), tubular & multi-nucleated - Voluntary - Uslly attached to skeleton 2. Smooth muscle - Fibres: non-striated, spindle-shaped & uninucleated - Involuntary - Uslly covering wall of internal organs 3. Cardiac muscle - Fibres: striated, branched & uninucleated - Involuntary - Only covering walls of the heart Paste pic pg35 6th learning outcome: describe the components of nervous tissue Nervous tissue - Nervous tissue composed of: glial cells (provides support) & neurones The 4 types of glial cells: Microglia A 1. Microfilm: - macrophages of the CNS M 2. Oligodendrocytes: Myelinate the axons within the CNS 0 3. Schwann cells: Myelinate the axons within the PNS S 4. Astrocytes: Supportive cells in the CNS