Respiratory 1 PDF

Respiratory 1 Dr Greg Davis Martini Chapter 23 Copyright notice  Objectives 1. Describe the primary functions of the respiratory system and explain how delicate respiratory exchange surfaces are protected from pathogens, debris and other hazards 2....

Respiratory 1 Dr Greg Davis Martini Chapter 23 Copyright notice  Objectives 1. Describe the primary functions of the respiratory system and explain how delicate respiratory exchange surfaces are protected from pathogens, debris and other hazards 2. Identify the organs of the upper respiratory system and describe their functions 3. Describe the structure of the larynx and discuss its role in normal breathing and sound production 4. Describe the structures of the extra-pulmonary airways 5. Describe the superficial anatomy of the lungs, including pulmonary lobules and alveoli  Function of the respiratory system Provide large area for gas exchange Move air to and from lungs Protect respiratory surfaces Produce sounds: speaking, singing, communication Detection of odours in superior section Overall view  Organisation Upper – Nose, nasal cavity, paranasal sinuses and pharynx Lower – Larynx, trachea, bronchi, bronchioles, alveoli Epithelium  Respiratory mucosa Respiratory mucosa contains – Superficial epithelia tissue with cilia and mucous cells – Deeper areolar tissue for support Defence – Mucous traps particles – In the nose particles > 10 µm are trapped – In the upper tract 1 – 5 µm are trapped – Cilia ‘beat’ upwards – muco-ciliary elevator to be swallowed Epithelial closer views  Nose and nasal cavity Provides: – an airway that humidifies, warms, cleans inhaled air – Structures that resonate for speech – location for olfactory receptors Nose breathing – Inhalation warms and humidifies air – Air mixed via conchae or turbines – exhalation removes moisture and heat  Pharynx Shared structure of respiratory and digestive systems superior portion extends from nose to mouth Middle portion Inferior portion extends to larynx Nose and nasal cavity Larynx  Larynx and glottis Larynx is structure that protects the glottis Glottis is the opening into the trachea – Normally closed to prevent inhalation of liquids etc – Production of sounds (see opera video) Glottis  Trachea Also known as windpipe Tracheal cartilage to support and keep tubing open Sits anterior to oesophagus (digestive tract) Branches into smaller structures (tubes) – Bronchi (right and left) – Bronchioles – Respiratory bronchioles (where air exchange takes place) The trachea Bronchial tree and lungs Tracheal branching  Respiratory portion (action site) Respiratory bronchioles Alveolar ducts Aveoli (150 million in each lung) Blood air barrier – Diffusion occurs rapidly across short distance – Diagram shows air and blood passageways Pulmonary lobule  Lungs as organs Two lungs that are different Left lung has 2 lobes, right lung 3 lobes Limited by other organs in the chest cavity Gas exchange is effected via pulmonary circuit Blood supply for lung tissue needs from systemic cirucit Another view  Summary 1. Describe the primary functions of the respiratory system and explain how delicate respiratory exchange surfaces are protected from pathogens, debris and other hazards 2. Identify the organs of the upper respiratory system and describe their functions 3. Describe the structure of the larynx and discuss its role in normal breathing and sound production 4. Describe the structures of the extra-pulmonary airways 5. Describe the superficial anatomy of the lungs, including pulmonary lobules and alveoli