Anatomy Lecture Notes

MC102-PM-LP-Unit 1-Topic 4  WEEK 4 The Epithelial Tissues The Connective tissues The bones and cartilages Classification and functions of glands _______________________________________ Prepared by Giovanni Clyde E. Rebadulla  INTRODUCTION ___________...

MC102-PM-LP-Unit 1-Topic 4  WEEK 4 The Epithelial Tissues The Connective tissues The bones and cartilages Classification and functions of glands _______________________________________ Prepared by Giovanni Clyde E. Rebadulla  INTRODUCTION _________________________________ This lesson module will serve as the basis for the students understanding on the different types of tissues in the human body. This also includes the glands , its classification and functions.  This Lesson Module 4 will cover the following : 1. Identify the body’s four major tissue types and describe their roles 2. Describe the relationship between form and function for each epithelial tissues. 3. Compare the structures and functions of the various types of connective tissues. 4. Describe the three types of muscle tissue and the special structural features of each. 5. Describe how aging affects the tissues of the body LEARNING OBJECTIVES: At the end of the module the student will be able to: 1. Identify the body’s four major tissue types and describe their roles 2. Describe the relationship between form and function for each epithelial tissues. 3. Compare the structures and functions of the various types of connective tissues. 4. Describe the three types of muscle tissue and the special structural features of each. 5. Describe how aging affects the tissues of the body Short Answer Assignment 1. What is a tissue and give examples 2. What is the difference between fertilization and implantation? 3. Specify the three germ layers and give examples 4. Summarize the different characteristics of Epithelial tissues 5. Make a list of the different characteristics of connective tissues. 6. What is a goblet cell? 7. What are the three main classification of glands? 8. Describe the three types of cartilages TISSUE, GLANDS AND MEMBRANES Tissue: are collection of similar cells and the substances surrounding them.  Extracellular matrix : Substances surrounding the cells.  Histology : Microscopic study of tissues.  BIOPSY : is the process of removing tissue sample from a patient surgically or with a needle for diagnostic purposes.  FERTILIZATION – Union of the ovum & spermatozoa. – Usually occurs in the ampulla of the fallopian tube. – Resulting structure is called a zygote.  FERTILIZATION  FERTILIZATION  IMPLANTATION ◦ Once fertilization is complete, the zygote migrates toward the body of the uterus. ◦ During this time, mitotic cell division begins. ◦ The implantation point is usually high in the uterus, on the posterior surface. ◦ Once implanted, the zygote is now called an embryo.  IMPLANTATION  EMBRYONIC TISSUES :  FERTILIZATION :  Endoderm (inner layer) Digestive tracts and related structures)  Ectoderm (outer layer) GERM LAYER (outer most layer of the skin) NEUROECTODERM : Nervous system Beak away cells: NEURAL CREST: > Peripheral Nerves, Skin pigments, Medulla and adrenal glands.  Mesoderm (middle) ( tissues: Bones, Muscles, blood vessels)  Germ Layer : Gives rise to all tissues in the body.  EPITHELIAL TISSUE : - Protective covering of external and internal surfaces of the body. Characteristics : 1. Covers the surfaces of the body and forms glands that are derived from the body surfaces. EX: Outside surface of the body, lining of cavities of intestine, respiratory tract and blood vessels. Epithelial cells of esophagus 2. Consist of entirely of cells with very little extracellular matrix between them. 3. Most epithelial cells have one free or apical surface not attached to each other cells: Lateral surface: Basal Surface : Attached to Basement Membrane 4. Epithelium does not contain blood vessels.  Functions of the epithelium 1. Protecting underlying structures 2. Acting as a barriers 3. Permitting the passage of substances ( Lungs) 4. Secreting substances 5. Absorbing Substances. Skin Esophagus  Classification of Epithelium By Number of cell layers 1. Simple Epithelium: Single layer of cells -For movement of materials ( lungs, glands, intestines) 2.Stratified Epithelium More then one layer of epithelial cells with some cells sitting on top of the other. - for protective functions - skin, throat, esophagus, vagina  By shapes of the cells 1. Squamous ( Flat and thin ) 2. Cuboidal ( Cube like) 3. Columnar ( Tall and Thin )  Simple Squamous Epithelium - Single layer of flat thin cells. - Where diffusion takes place - Secretes slippery fluid that prevents abrasions between organs.  SIMPLE CUBOIDAL Epithelium - Single layer of cuboidal cells that carry active transport, facilitated diffusion or secretions. - Greater volume with more organelles. - Active transport ( ATP) - Secretes waste products into the tubules and reabsorb products into the tubules. - (+) Some have cilia SIMPLE COLUMNAR EPITHELIUM - Is a single layer of tall thin cells - Produce and secretes mucous and digestive enzymes in the small intestines.  PSEUDOSTRATIFIED Columnar Epithelium - False stratified - Just one layer of cells attached to the basement membrane. - Respiratory :Nasal cavity, pharynx, trachea - Secretes Mucous STRATIFIED SQUAMOUS EPITHELIUM - Consist of several layers ( Thick ) - Cuboidal and columnar in layers that are capable of dividing and pushing the new cells to the surface. - Classification : a. NON- Keratinized ( Moist) - Mouth, esophagus, rectum, vagina, Deeper layer : living cells Outer layers : Dead cells wit keratins. b. Keratinized.  NON Keratinized  KERATINIZED  Stratified Cuboidal Epithelium - Two or more than one layer of cuboidal epithelial cells. - sweat glands , ovarian follicles and salivary glands. - for absorption, secretions ,and protection.  Stratified Columnar Epithelium - more than one layer of epithelial cells but only the but only the surface are epithelial in shape. The deeper layers are irregularly cuboidal. - larynx, male urethra and trachea. - Protection, secretions and absorption  GOBLET CELLS : - Columnar cells which secretes a clear and viscous materials called mucous. - - protects the layers of intestines against the digestive enzymes and acids produces by the stomach.  TRANSITIONAL EPITHELIUM - can be greatly stretched. - urinary bladder. ureter, kidney, pelvis and calyces - also protects the bladder from the caustic effects of urine  CELL Connections - TIGHT JUNCTION : bind cells together and form permeability barriers. - prevent the passage of materials between the epithelial cells. - found in small intestine  DESMOSOMES : - Are mechanical bodies that bind cells together Hemi desmosomes: - anchor the cells to the basement membranes. GAP JUNCTIONS : - Small proteins channels that allows small molecules and ions to pass from one epithelial cells to adjacent one. - Acts as communication signals to coordinate the activities of the cells.  CONNECTIVE TISSUE : - it consist of cells separated from each other by abundant extracellular matrix. Functions : 1.Enclosing and separating : capsules around organs Separates muscles, arteries and veins and nerves 2.Connecting Tissues to one another. Tendons : cable of bands of connective tissues that attach muscles to bones Ligaments : are connective tissue bands that holds the bones together. 3. Supporting and moving : -skeletons provide support for the body - cartilage: semi rigid structure that supports joint surfaces, ears and nose. - Joints : between bones allow one part of the body to move relative to other parts. 4. Storing : Adipose tissue stores fats Bones stores minerals, calcium and phosphates. 5. Cushion and insulation : Adipose tissue protects the tissue that surrounds it - means to conserve heat. 6. Transportation : Blood transports hormones, enzymes, nutrients to different parts of the body. 7. Protecting : Blood and immune system provide protection against toxins and tissue injury and microorganisms. CELLS AND EXTRACELLULAR MATRIX Blasts : germ cells that produce he cell matrix Ex. Fibroblasts: cells that forms fibers and ground substances in the fibrous connective tissue. Osteoblasts : form the bones Cyte : (cells) Cells maintain it Fibrocytes: cells that maintain the connective tissues Osteocytes: maintain the bones Clasts : ( clasts)Cells break it down for remodeling purposes. Osteoclasts : breakdown the bones. Cells in the immune System that are found in the connective tissue. Macrophages : ingest foreign substances, microorganism and connective tissue. Mast Cells : Release histamine that promotes inflammation.  Three major components of Extracellular Matrix : 1. PROTEIN FIBERS: A. COLLAGEN fibers : are like ropes, flexible but resists stretching B. RETICULAR FIBERS : - fine, short collagen fibers that branch to form supporting network. C. ELASTIC FIBERS : have a structure similar to the coiled metal bed springs.. If stretched, they can recoil to back to the original shapes. 2. GROUND SUBSTANCE - shapeless background seen in light microscopes but its molecules are highly structured.. 3.PROTEOGLYCANS: - holds large quantities of water. FREE CELL SURFACES : Smooth surface : reduce friction as blood flows in the blood vessels Microvilli : cylindrical extension of cell membranes that increases the cell surface area. CILIA : Propel materials along the surface of the cells. - in the nasal cavity and trachea. CLASSIFICATION OF CONNECTIVE TISSUE Mesenchyme : the origin of the connective tissue. Major Categories of Connective tissue A. Loose or Areolar Connective tissue - consist of elastin and Collagen fibers. Fibroblast: most common cell in the ACT. - fills the spaces between muscles, glands and nerves 2.DENSE CONNECTIVE TISSUE - Densely packed fibers produced by fibroblasts. Types: 1. DENSE regular Connective tissue. - Protein fibers in the extracellular matrix are oriented in one directions. - Dense Regular collagenous Connective tissue: - has abundant collagen fibers, resist stretching and give strength ( Ligaments ) - Dense regular Elastic Connective Tissue. - consist of Parallel bundles of collagen and elastic fibers. ( vocal cords and ligaments in the vertebrae) DENSE IRREGULAR CONNECTIVE TISSUE - Random orientation of protein fibers ( meshwork) DENSE IRREGULAR COLLAGENOUS CONNECTIVE TISSUE - found in the dermis of the skin, and in capsules in the kidney and spleen. DENSE IRREGULAR ELASTIC CONNECTIVE TISSUE - In the walls of elastic arteries. Connective Tissue with special Properties ADIPOSE TISSUE : - Adipocytes( Fat cells ) are filled with lipids, large and closely packed together. - store energy - acts as pads and protects parts of the body. - acts as Thermal insulators. - Yellow Bone marrow: Adipose tissue within the cavities of the bones. RETICULAR TISSUE : - Reticular fibers are produced by Reticular cells. - forms the framework of lymphatic tissue - present in spleen and lymph node, bone marrow and liver. CARTILAGE : - Chondrocytes: cartilage cells ; located in space >> Lacunae. - has Collagen and proteoglycans - provides support. - resumes back to its original shape if compressed. - heals slowly. Types of Cartilage: 1.Hyaline cartilage - Most abundant - covers the bones to form joints - Ex: Cartilage rings of respiratory tracts, 2. FIBROCARTILAGE: - with bundles of collagen fibers - Resist pulling and tearing forces. - Ex: Disk within vertebra 3. Elastic cartilage : - (+) Elastic fibers plus collagen and proteoglycans. BONE : hard connective tissue that consist of a living cells and a mineralized matrix. - Osteocytes: Bone cells. Lacunae: spaces where the cells are embedded Types of Bones: 1. Compact Bones : has more bones than spaces. Lamellae : thin layers of bones organized to become a bone matrix. 2. Cancellous or Spongy Bones - Resembles a sponge. - Has spaces between trabeculae GLANDS - secretory structure: secretes hormones - classification: a. Unicellular : Goblet cells b. Multicellular : Endocrine : ( Inside)Do not have ducts Exocrone: (Outside) release the secretions into cavities. Ex : Sweat gland and mammary glands  Classification based on the number of ducts: 1. Simple : One duct 2. Compound: glands with ducts that branch repeatedly  Classification based on the ends of the ducts: a. Tubular : ends in tubules ( straight or Coiled) b. Acini : ends in sac like structures c. Alveoli : ends in a hollow sacs.  Classification based on how the cells leave the cell 1. Merocrine glands : Water producing sweat glands 2. Apocrine glands : milk in mammary glands 3. Holocrine glands : Sebaceous glands on the skin. SUMMARY You have just learned: 1. The description and functions of the epithelial tissues 2. The description and functions of the connective tissues 3. The different types of glands 4. The main difference between a bone and a cartilage. REFERENCES Peate,I and Nair,M,2016.Fundamentals of Anatomy and Physiology: For Nursing and Healthcare Students Retrieved from: https://www.pdfdrive.com/fundamentals-of-anatomy-and-physiology- for-nursing-and-healthcare-students-e176005292.html Waugh,A and Grant,A,2016. ROSS AND WILSON ANATOMY AND PHYSIOLOGY IN HEALTH AND ILLNESS,11th Edition Retrieved from: https://www.pdfdrive.com/ross-and-wilson-anatomy-and-physiology-in- health-and-illness-eleventh-edition-anne-e128005641.html Thank you