Respiratory System PDF

RESPIRATORY SYSTEM Prepared by: Antoinette P. Dela Cruz Types of Respiration Direct Respiration – type of respiration of unicellular organisms. Since they are composed of single cell, respiration is direct through their cell membrane. Indirect Respiration – type of respiration of multic...

RESPIRATORY SYSTEM Prepared by: Antoinette P. Dela Cruz Types of Respiration Direct Respiration – type of respiration of unicellular organisms. Since they are composed of single cell, respiration is direct through their cell membrane. Indirect Respiration – type of respiration of multicellular organisms. Since these organisms are composed of many cell, a lot of cells are no longer in contact with the environment, so they used specialized organ for respiration and that is the respiratory system. Stages of Indirect Respiration External – exchange of gasses between the environment and the blood. Internal – exchange of gasses between the blood and the cells. Also known as cellular respiration. Function of the Respiratory System Oversees gas exchange between the blood and external environment Exchange of gasses takes place within the alveoli Passage ways to the lungs purify, warm, and humidify the incoming air. Acquire O2 which the body will use in aiding the digestion of food we take Eliminating CO2 which is the by-product of the digestion process The respiratory surface Surfaces where oxygen and carbon dioxide diffuses through the plasma membrane Must be wet and thin to allow diffusion Must be extensive to be able to supply enough oxygen Four Types of Animal Respiratory Organ Skin (earthworms, frogs, and amphibians) Gills (fishes) Tracheae (insects) Lungs (amphibians, reptiles, birds, and mammals) Organs of the Respiratory System 1. Nose 2. Pharynx 3. Larynx 4. Trachea 5. Bronchi 6. Lungs - alveoli  PARTS OF THE RESPIRATORY SYSTEM 1. Nose The only externally visible part of the respiratory system Air enters the nose through the external nares (nostrils) The interior of the nose consists of a nasal cavity divided by a nasal septum 2. Pharynx (Throat) Muscular passage from nasal cavity to larynx Three regions of the pharynx – Nasopharynx: superior regions behind nasal cavity – Oropharynx: middle region behind mouth – Laryngopharynx: inferior region attached to larynx The oropharynx and laryngopharynx are common passageways for air and food 3. Larynx Also known as the voice box Routes air and food into proper channels Plays a role in speech Made of eight rigid hyaline cartilages and a spoon-shaped flap of elastic cartilage (epiglottis) Vocal cords – vibrate with expelled air to create sound (speech) Structure of Larynx Thyroid Cartilage – Largest hyaline cartilage – Protrudes anteriorly (Adam’s Apple) Epiglottis – Superior opening of the larynx Glottis – Opening between vocal cords 4. Trachea Also known as the windpipe Lined with ciliated mucosa – Beat continuously in the opposite direction of incoming air – Expel mucus loaded with dust and other debris away from lungs Walls are reinforced with C- shaped hyaline cartilage 5. Primary Bronchi Formed by division of the trachea Enters the lung at the hilus (medial depression) Right bronchus is wider, shorter, and straighter than left Bronchi is subdivided into smaller and smaller branches 6. Lungs Occupy most of thoracic cavity – Apex is near the clavicle (superior portion) – Each lungs is divided into lobes by fissures Left Lung – two lobes Right Lung – three lobes 7. Bronchioles Smallest branches of the bronchi All but the smallest branches have reinforcing cartilage Terminal bronchioles end in alveoli 8. Alveoli Structure of Alveoli – Alveolar duct – Alveolar sac – alveolus Gas exchange takes place within the alveoli in the respiratory membrane Squamous epithelial lining alveolar walls Covered with pulmonary capillaries on external surfaces GAS EXCHANGE Gas crosses the respiratory membrane by diffusion – oxygen enters the blood – Carbon dioxide enters the alveoli Macrophages add protection Surfactant coats gas-exposed alveolar surfaces Air-Blood Barrier of the Respiratory Membrane Respiratory Disorders Emphysema – Alveoli enlarge as adjacent chambers break through; chronic inflammation promotes lung fibrosis; airways collapse during expiration; Cyanosis appears late in the disease Chronic Bronchitis – inflammation of the mucosa of the lower respiratory passages; mucus production increases; pooled mucus impairs ventilation and gas exchanges; risk of lung cancer increases; Hypoxia and cyanosis occur early Lung Cancer – increased incidence associated with smoking; three common types: (1) squamous cell carcinoma, (2) adenocarcinoma, and (3) small cell carcinoma Sudden Infant Death Syndrome (SIDS) – healthy infants stops breathing and dies during sleep; some cases are thought to be a problem of the neural respiratory control center. Asthma – chronic inflammation if the bronchiole passages; response to irritants with dyspnea, coughing, and wheezing  END I do not own the images, videos, and information in this presentation. Credits are to the owners