2024_MSPC_112_BAHS_102_RESPIRATORY SYSTEM.pptx

RESPIRATORY SYSTEM NK3 OBJECTIVES At the end of this lecture, students should be able to:  Describe the organisation of the Respiratory System  Describe the respiratory epithelium  Name and describe the structure of the component parts and organs of...

RESPIRATORY SYSTEM NK3 OBJECTIVES At the end of this lecture, students should be able to:  Describe the organisation of the Respiratory System  Describe the respiratory epithelium  Name and describe the structure of the component parts and organs of the Respiratory System Resources  https://www.youtube.com/playlist?app=deskto p&list=PLF2PbpJOr9t1iyNEpVEowrlrHwu5_clMz Respiratory System  Provides means for gas exchange required by living cell. RS and CVS are inseparable. Whiles the RS exchanges gases between atmosphere and the blood the CVS transports those gases between the lungs and blood Function  Pulmonary ventilation (Breathing)  leads to gas exchange  Inhalation (inspiration)  Draws gases into the lungs  Exhalation (expiration)  Forces gases out of the lungs  Oxygen is drawn into the lungs by inhalation  Oxygen is transported to body cells through circulatory system  Carbon dioxide is by product from tissues  Carbon dioxide is added to atmosphere through exhalation Function  Sound production  Air forced through larynx, sound may be produced  Olfaction  Olfactory epithelium  Receptors for smell  Defense  Which structures?  Gas conditioning  warmed to body temperature  humidified (moistened)  cleansed of particulate matter through contact with respiratory matter and its sticky mucus covering. Respiratory System  Anatomically Upper respiratory tract Lower respiratory tract  Functionally Conducting portion= nose, nasal cavity, pharynx, larynx, trachea, primary bronchi to terminal bronchi Respiratory portion = respiratory bronchioles, alveolar ducts, alveoli (air sacs)  Organisation Structural Functional Divisions Divisions Upper Respiratory Tract Conducting Portion right Respiratory lung Portion Lower Respiratory Tract left lung Respiratory System  Components  Respiratory epithelium  becomes simple in bronchioles with cilia disappearing.  Read: Squamous Metaplasia  Mucosa  Cell types Ciliated columnar cells. Kartagener's syndrome Goblet cells Brush cells : many microvilli Basal cells: short stem cells giving rise to other cells  Lamina propria  Submucosa  Cartilage  Smooth muscle ©Regents of the University of Michigan Histological changes along the respiratory tree Assignment - Upper Respiratory Tract  Read on the Nose and Nasal cavity, Paranasal Sinuses, Pharynx.  Make sure you know all the Anatomical parts!!!!!!!  What constitute the Upper and Lower respiratory Tract?  Upper and Lower Respiratory Tract Structural Functional Divisions Divisions Upper Respiratory Tract Conducting Portion right Respiratory lung Portion Lower Respiratory Tract left lung Histological features of the nasal cavity Upper Respiratory Tract - Functions  Nose and Nasal  Pharynx: Passage Cavity; Filtration, between nasal cavity Conditioning, and larynx, passage Olfaction and Sound for swallowed food Production. and drink between  Paranasal Sinuses: oral cavity and decrease skull bone oesophagus weight, Cleanse air  Nasopharynx and serve as  Oropharynx chamber for sound  Laryngopharynx resonance  Frontal, ethmoidal, sphenoidal and maxillary sinuses  Lower Respiratory Tract  Larynx (Voice box)  Supported by a  Laryngopharynx - superior framework of 9  Esophagus – posterior pieces of cartilage (3  Trachea – inferior individual pieces and  Stratified squamous non – 3 pairs of cartilage), keratinizing and ligaments and pseudostratified ciliated skeletal muscles columnar epithelium  Thyroid cartilage  Functions  Cricoid cartilage  Prevents swallowed material from entering the lower  Epiglottis respiratory tract  Arytenoid  Conducts air into lower  Corniculate respiratory tract  Cuneiform  Produces sound Larynx – Cartilages  Trachea Main (10) Bronchi Lobar (20) Bronchi Segmental (30) Bronchi Bronchioles Trachea is Anterior to...... inferior to........ and superior to...... a. Esophagus, larynx, stomach b. Pharynx, bronchiole, primary bronchi c. Esophagus, larynx, primary bronchi Tracheobronchial Tree d. Rib cage, diaphragm, Trachea - Features Cartilage Rings Anular ligaments (elastic sheets) Epithelium Trachealis muscle Carina Question  In chronic smokers, the lining of the trachea and bronchi changes from pseudostratified ciliated columnar epithelium to a stratified squamous epithelium.  A. Why do you think this change occurs  B. What are some consequences of this epithelium in the trachea Bronchial Tree  Originate from Left and Right primary bronchus progressively branch into narrow tubes ending in terminal bronchioles.  Right primary bronchus is shorter wider and more vertically oriented.  Primary bronchi enter hilum of lung with Pulmonary vessel, lymphatic vessel and nerves.  Right Primary bronchi has 3 secondary bronchi  How many does the left have?  What is a bronchopulmonary segment?  Features Bronchi 10, 20, 30 Incomplete cartilage Rings Epithelium Smooth muscle Bronchioles  Diameter less than 1mm  Simple columnar or cubiodal epithelium  No cartilage  Thick layer of smooth muscle (bronchoconstriction and bronchodilation)  Terminal bronchioles are final segment of conducting pathway. Conduct air into respiratory portion Features Bronchioles No Cartilage Rings Epithelium Clara cells Termination  Respiratory Portion Function Site for gaseous exchange Thin epithelium Components Respiratory Bronchioles Alveolar Duct (S. Squamous) Alveoli Alveolar sac  Alveoli Wall consists of surface epithelium, supporting tissue and blood vessels Surface Epithelium Type I Pneumocytes (alveolar lining cells) – form gaseous diffusion barrier Type II Pneumocytes – Produce surfactant: fluid that coats the inner aveoli surface to reduce surface tension and prevent collapse of the aveoli Alveolar Macrophages (Dust cells)  Function To oxygenate Lungs blood House the bronchial tree and the respiratory portion of the respiratory system Location Within two pulmonary cavities separated by the mediastinu  Lungs Lined with serous membrane called Pleura Features Hilum / root Apex Fissures Lobes Left smaller than right Questions  Which statement is false about the trachea? A. It is not lined with nonkeratinized stratified squamous epithelium B. It is continuous superiorly with the larynx C. It bifurcates into left and right primary bronchi at the level of the sternal angle D. It contains C shaped cartilage rings E. None of the above Question Noted Anatomist David Morton  Which structure is the last smallest portion of the conducting pathway? A. nasopharynx B. terminal bronchiole C. respiratory bronchiole D. alveolus Sample Final Examination Question For each of the following questions answer: a. If only i, ii and iii are correct b. If only i and iii are correct c. If only ii and iv are correct d. If only iv are correct e. If all are correct 1. Which of the following statements is/are correct regarding epithelia? i. Stratified squamous epithelia lines surfaces that are subject to abrasion ii. Transitional epithelium is well adapted for absorptive functions iii. All cells of pseudostratified epithelium reach the basement membrane but not all of them reach the luminal surface iv. Epithelial cells usually receive nutritive substances from capillaries located in the intercellular spaces of the epithelium Sample Final Examination Question Cells that are actively involved in the phagocytosis of extracellular material would contain high levels of which of the following cellular organelles? a. Rough endoplasmic reticulum b. Golgi apparatus c. Lysosomes d. Smooth endoplasmic reticulum e. Ribosomes Sample Final Examination Question In the circulatory system which of these vessels is responsible for direct regulation of amount of blood flow into tissues of the body? a. Arteriole b. Capillaries c. Venule d. Arteries e. Large vein Sample Final Examination Question Which muscle type is needed for facial expressions and gestures? a. Skeletal b. Smooth c. Cardiac d. A and B e. None of the above Sample Final Examination Question Which supporting cells in the central nervous system produce myelin sheath? a. Protoplasmic Astrocytes b. Fibrous Astrocytes c. Ependymal cells d. Schwann cells e. Oligodendrocytes Sample Final Examination Question Why is the developing human most susceptible to teratogenic insults during the embryonic period of development? a. Cells produced in embryonic period being totipotential have receptors for all molecules and fail to distinguish good and harmful ligands. b. Deleterious factors in the embryonic period of development prevent the formation of a zygote, so an embryo does not come into being at all. c. Organogenesis in the embryonic period involves massive mitosis and migration of cells in a tightly ordered sequence of timing that is vulnerable to toxic interference. d. Pre-embryonic development involves no mitotic activity and morphogenetic movements. e. When disrupted by toxic insults, embryonic development fails to produce an embryo. Sample Final Examination Question In a hospital near your home, a 2-year-old girl was brought in with Retinoblastoma that has affected both eyes. Which of the following terms will you use to describe such presentation? a. Unilateral b. Contralateral c. Bilateral d. Ipsilateral e. Cephalic