Presentation on theme: "ST120 Concorde Career College, Portland. Objectives Define the term respiration. Describe the functions of the respiratory system."— Presentation transcript:
ST120 Concorde Career College, Portland
Objectives Define the term respiration. Describe the functions of the respiratory system.
Objectives List and identify the structures of the respiratory system and describe the function of each.
Objectives Describe the process of respiration. Describe the mechanism by which the respiratory system helps to maintain homeostasis.
Objectives Describe common diseases, disorders, and conditions of the respiratory system including signs and symptoms, diagnosis, and available treatment options. Demonstrate knowledge of medical terminology related to the respiratory system verbally and in the written form.
Respiration More than breathing in and out. Process by which oxygen is obtained from the environment, delivered to the cells, and waste products such as carbon dioxide are removed from the body.
Terms Respiration- Inhaling and exhaling facilitate the process of taking in oxygen and getting rid of waste CO2. Internal respiration- exchange of O2 and CO2 between the blood and body cells. External respiration- exchange of O2 and CO2 between the lungs and the circulatory system. Cellular respiration- the use of O2 by the cells of the body & production of CO2. Ventilation- movement of air in & out of the lungs (breathing)
Functions of the Respiratory System Pulmonary ventilation Inhalation Exhalation Diffusion of gases Into and out of the blood Transport to and from the cells (cellular respiration) Oxygen Carbon dioxide
Primary Structures of the Respiratory System Nasal cavities Pharynx Larynx Trachea Lungs Diaphragm
Upper Respiratory Tract Nose- Covered by skin and supported by bone and cartilage. Air enters through the external nares and coarse hairs line the internal part of the nares to act as filters. Nasal Cavities Separated by nasal septum. Lining is made of ciliated epithelium (nasal mucosa). Highly vascularized, which warms inhaled air. Nasal conchae Curved scroll-like bones Superior, middle, and inferior turbinates
Lower Respiratory Tract Larynx “voice box” contains vocal cords (2 short fibrous bands that stretch across the interior of the larynx) The space between the vocal cords is called the glottis Connects pharynx to trachea Serves as part of the air passageway Lined with mucous membrane Composed of cartilaginous rings: ○ Thyroid Adam’s apple = thyroid cartilage ○ Cricoid Sellick’s maneuver
Lower Respiratory Tract Larynx During swallowing, larynx elevates & epiglottis closes over opening to prevent food from entering Vocal cords-located on either side of glottis ○ Breathing- cords close over glottis. ○ Speaking- cords are stretched & exhaled air vibrates cords causing speech.
Lower Respiratory Tract Trachea “wind pipe” Extends from layrnx to carina Composed of 20 C-shaped rings of hyaline cartilage. ○ Flexible, keep trachea continuously open. Primary bronchi = right and left bronchus Mediastinal space Lined w/ resp. epithelium Enter lung & continue to divide ○ AKA “bronchial tree”
Trachea & Bronchi
Respiratory System Bronchi Trachea divides (bifurcates) into two primary bronchi Secondary bronchi Tertiary bronchi Bronchioles
Lower Respiratory Tract Bronchioles Simple epithelium Lack cilia, goblet cells, & cartilage Contain smooth muscle bundles-regulate diameter of lumen Exchange of gases Divide into alveolar ducts w/ alveoli surrounding each duct = alveolar ducts
Pleural Cavity Pleura = covers the outer surface of lungs and the lining of the inner surface of the rib cage Parietal pleura lines the walls of the thoracic cavity Visceral pleura covers the lungs Contains: Lungs Pleural membranes ○ divided into parietal pleura and visceral pleura ○ Pleural space- space between parietal & visceral pleura, contains serous fluid,
Respiratory System Alveoli Located at the end of the terminal bronchioles Tiny sacs surrounded by vascular capillaries Gas (O 2 and CO 2 ) occurs in the alveoli
Pleural Cavity Alveoli Primary functioning unit Responsible for gas exchange Alveolar walls Squamous epithelial cells-type 1 pneumocytes Each alveolus is surrounded by pulmonary capillaries ○ Consist of a single layer of endothelial cells ○ A thin, filmy layer of fluid that covers the alveoli to reduce surface tension forces and aid in the expansion of alveoli is called Pulmonary Surfactant
Cluster of Alveoli at the Terminal Bronchiole
Pleural Cavity Alveolar-capillary barrier 3 layers ○ Between air in alveoli & blood in pulmonary capillaries Pneumocytes Type 2 ○ round in shape ○ Contain large nucleus Lamellar bodies-contain phospholipids that release surfactant One alveolar sac is made up of numerous alveoli pg. 293 A&P
Microscopic View of Alveolar Sac
Pleural Cavity Diaphragm Separates thoracic & abdominal cavity Divided into: ○ Crura ○ Central tendon Subdivided into 3 divisions-leaflets Major openings ○ Aortic ○ Esophageal ○ Inferior vena cava The diaphragm muscle flattens out when it contracts during inspiration The diaphragm muscle returns to upward position during expiration
Pleural Cavity Diaphragm Blood supply ○ Branches of internal thoracic arteries Thoracic aorta Inferior phrenic arteries Lymph nodes ○ Located on superior surface ○ Receive drainage from liver & esophagogastric junction
Pleural Cavity Intercostal muscles Located between ribs Divided: ○ External intercostal muscles covered by intercostal fascia Intercostal nerves innervate muscles ○ Primary structures responsible for movement during respiration.
Pulmonary and Systemic Circuits Pulmonary circuit From the heart to the lungs and back to the heart Systemic circuit From the heart to the tissues and back to the heart
External Respiration O2 diffuses from alveoli into blood CO2 diffuses from blood to alveoli Blood high in O2 returns to heart, pumped out by left ventricle through the aorta to the body Exchange of gasses between the blood and the lungs by diffusion
Internal Respiration O2 diffuses from blood to body cells CO2 diffuses from body cells to blood Venous blood is low in O2 returns to right ventricle to lungs for reoxygenation.
Regulation of Respiratory System Nervous system Medulla ○ Responsible for inspiration & expiration Pons ○ Regulates normal rhythm of breathing Centers -apneustic center -Pneumotaxic center
Regulation of Respiratory System Nervous System Chemoreceptors ○ Located in medulla, aortic bodies & carotid bodies ○ Detect changes in pH & blood gas levels Phrenic nerve stimulates the diaphragm
Respiratory Monitors Pulmonary volumes Tidal volume Minute ventilation Inspiratory reserve volume Expiratory reserve volume – amount of air that can be forcibly exhaled after expiring the total volume Vital capacity – largest amount of air we can breathe out in one expiration Residual volume Total lung capacity Forced expiratory volume
Conditions Pulmonary edema-abnormal accumulation of fluid in extravascular spaces or alveoli Pneumothorax-abnormal accumulation of air between the parietal & visceral pleura Pneumonia- acute infection of lungs Chronic Obstructive Pulmonary Disease (COPD)-chronic airway obstruction Emphysema-abnormal, irreversible enlargement of the alveoli due to destruction of alveolar walls Pleurisy-Inflammation of the pleura that causes pain when the membranes rub together
Why is a tracheotomy done? - Gain access to airway before blockage - Create an open airway for breathing
Pulmonary Lobectomy Excision of one or more lobes Performed to excise benign lesions, malignant and metastatic malignant lesions