Respiratory System Anatomy Copyright 1999, Stephen G. Davenport, No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form without prior written permission. 7/5/02 Mr. Davenport 1
Functions of the Respiratory System Provides surface area for gas exchange Moving air to and from exchange surfaces Protection of surfaces from dehydration Production of sounds (vocal apparatus) Providing olfactory sensations 7/5/02 Mr. Davenport 2
Chest x-ray 7/5/02 Mr. Davenport 3
Nose and Nasal Cavity Nose Functions include Provides an airway Moistens and warm air Filters Resonation for sound Houses olfactory receptors Primary passageway of skin covered bone and cartilage External nares (nostrils) 7/5/02 Mr. Davenport 4
Nasal Cavity External nares (nostrils) airway entrance Vestibule is inlet superior to nostrils Nasal septum divides right and left portions Conchae (pl, kong -ke; sing., concha, kong kah) are three bony projects into cavity Meatuses (pl, me-a -tus-es; sing. meatus, me-a -tus) are airway grooves formed by the conchae Internal nares (nar -ez) are posterior openings from nasal cavity into nasal pharynx (throat) 7/5/02 Mr. Davenport 5
Nasal Cavity Mucosa Lined with pseudostratified ciliated columnar epithelium Numerous goblet cells, with mucous and serous glands in underlying connective tissue 7/5/02 Mr. Davenport 6
Pharynx (FAR-inks) Pharynx is commonly called throat Nasopharynx (internal nares to soft palate) Auditory tubes (pharyngotympanic or eustachian) Pharyngeal tonsil (adenoid) Oropharynx (soft palate to hyoid bone) Uvula Laryngopharynx (hyoid bone to cricoid cartilage and esophagus) 7/5/02 Mr. Davenport 7
Larynx (LAR-inks) Commonly called the voice box Thyroid cartilage Cricoid cartilage Epiglottis Vocal folds (cords) Ventricular folds Glottis 7/5/02 Mr. Davenport 8
Trachea (TRĀ-kē-uh) Trachea extends from larynx to primary bronchi Three layers: mucosa: pseudostratified ciliated columnar epithelium submucosa: seromucous glands in connective tissue adventitia: hyaline cartilage C rings and dense connective tissue 7/5/02 Mr. Davenport 9
TRACHEA Cilia Goblet cell Mucosa Pseudostratified ciliated columnar epithelium Submucosa Seromucous glands Adventitia Hyaline cartilage 7/5/02 Mr. Davenport 10
TRACHEA 8 1 Mucosa 2 Submucosa 3 Adventitia 4 Ciliated pseudostratified columnar epithelium 5 Goblet cells 6 Seromucous glands 7 Hyaline cartilage 8 Cilia 7/5/02 Mr. Davenport 11 Photograph 2
Primary Bronchi (BRONG-kī) Primary bronchi are the two branches from trachea Right and left primary bronchi Right is larger in diameter and steeper angle 7/5/02 Mr. Davenport 12
Lungs Left lung - two lobes (superior, inferior) cardiac notch Right lung - three lobes (superior, middle, inferior) Apex of each lung is just inferior to each clavicle Base of each lung rests upon the diaphragm Costal surface rest near the ribs (anterior, lateral, and posterior) Root is where vascular and bronchial attachments enter the lung (the indentation called the hilus). 7/5/02 Mr. Davenport 13
Pleural Coverings Plumonary pleura is the serous membrane of the lung Parietal pleura is the region associated with the thoracic wall surrounding each lung Visceral pleura is the region associated with the surface of each lung Each lung has a potential space, the pleural cavity, which contains serous fluid. 7/5/02 Mr. Davenport 14
Bronchial tree The Conducting Zone Consists of primary bronchi and their branches primary bronchi secondary (lobar) bronchi tertiary (segmental) bronchi terminal bronchioles 7/5/02 Mr. Davenport 15
Bronchial tree Decrease in size results in decreased amounts of cartilage increased amounts of smooth muscle Bronchioles vary airway resistance Bronchodilation - sympathetic Bronchoconstriction parasympathetic Also chemical mediators such as histamine 7/5/02 Mr. Davenport 16
Respiratory Zone Respiratory bronchioles have alveoli (air sacs) associated with their wall Alveolar ducts originate from respiratory bronchioles and lead into groups of air sacs called alveolar sacs 7/5/02 Mr. Davenport 17
Alveoli Located individually (respiratory bronchioles) and grouped into alveolar sacs Sites of gas exchange Surrounded by capillaries and elastic tissue 7/5/02 Mr. Davenport 18
Alveolus Alveolar epithelium is simple squamous Alveolar macrophages roam epithelium Septal cells produce surfactant (sur-fac-tant) which reduces surface tension 7/5/02 Mr. Davenport 19
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Respiratory Membrane Site of gas exchange Consists of endothelium basement membranes alveolar epithelium (simple squamous) Fused basement membranes Red blood cell Endothelium Alveolar epithelium (simple squamous) 7/5/02 Mr. Davenport 21
Respiratory Membrane Driving force for gas exchange is diffusion Two reasons diffusion proceeds rapidly: Distance across membrane is small Oxygen and carbon dioxide are lipid soluble 7/5/02 Mr. Davenport 22