NURSE-UP RESPIRATORY SYSTEM

NURSE-UP RESPIRATORY SYSTEM

FUNCTIONS OF THE RESPIRATORY SYSTEM Pulmonary Ventilation - Breathing Gas exchanger External Respiration between lungs and bloodstream Internal Respiration between bloodstream and tissues Filters, warms, and humidifies air Influences speech - phonation Allows for sense of smell

RESPIRATORY SYSTEM ANATOMY Structurally Upper respiratory system Nose, nasal cavity, sinuses, pharynx and part of the larynx Lower respiratory system Part of the larynx, trachea, bronchi and lungs Functionally Conducting zone conducts air to lungs Nose, pharynx, larynx, trachea, bronchi, bronchioles and terminal bronchioles Respiratory zone main site of gas exchange Respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli

UPPER RESPIRATORY TRACT Nose Nasal Cavity Sinuses Pharynx Larynx*

THE NOSE Provides an airway for respiration Moistens and warms air Filters inhaled air Resonating chamber for speech Houses olfactory receptors Skin is thin contains many sebaceous glands

THE NASAL CAVITY External nares nostrils Divided by nasal septum Vestibule - anterior opening Two types of mucous membrane Olfactory mucosa - Near roof of nasal cavity, houses olfactory (smell) receptors Respiratory mucosa - Lines nasal cavity Epithelium is pseudostratified ciliated columnar Goblet cells within epithelium Cilia move contaminated mucus posteriorly

NASAL CONCHAE 3 paired bony projections along the lateral walls of the nasal cavity Superior and middle nasal conchae - part of the ethmoid bone Inferior nasal conchae - separate bone Nasal conchae subdivide cavity into meatuses Increase surface area and prevents dehydration Function - Particulate matter deflected to mucus-coated surfaces

THE PARANASAL SINUSES Sinuses in bones that surround the nasal cavity Sinuses lighten the skull and help to warm and moisten the air

PHARYNX Starts at internal nares and extends to cricoid cartilage of larynx Contraction of skeletal muscles assists in deglutition (swallowing). Functions Passageway for air and food Resonating chamber Houses tonsils 3 anatomical regions Nasopharynx Oropharynx Laryngopharynx

NASOPHARYNX Behind nose to soft palate. Filters bacteria and foreign particles from inspired air Eustachian tube and auditory tube open into lateral surfaces, connect nasopharynx to middle ear, equalizes pressure of middle ear

OROPHARYNX Behind mouth, from soft palate to hyoid bone, From tip of uvula to epiglottis ensures that air travels through the windpipe while food and water travel through the esophagus Stratified squamous epithelium Gas conduction, filtering of air Defense mechanism: gag reflex

LARYNGOPHARYNX Hyoid bone to esophagus. Stratified squamous epithelium Gas conduction Connecting zone between upper and lower airway (vocal cords and below)

THE LARYNX Prevent food and drink from entering the trachea Passageway for air Produces Sound Connects laryngopharynx with trachea Epithelium of the larynx Stratified squamous superior portion Pseudostratified ciliated columnar inferior portion

CARTILAGES OF THE LARYNX Thyroid cartilage - shield-shaped, forms laryngeal prominence (Adam s apple) applies tension to vocal folds Three pairs of small cartilages support vocal folds Arytenoid cartilages Corniculate cartilages Cuneiform cartilages Epiglottis - tips inferiorly during swallowing covers opening to trachea.

THE LARYNX Vocal ligaments of the larynx Vestibular or Ventricular folds (false vocal cords) Superior pair No role in sound production Function in holding breath against pressure in thoracic cavity Vocal folds (true vocal cords) - act in sound production inferior pair Muscle contraction pulls elastic ligaments which stretch vocal folds out into airway vibrate and produce sound with air folds can move apart or together, elongate or shorten, tighter or looser Voice production Length of the vocal folds changes with pitch Loudness depends on the force of air across the vocal folds

VOCAL CORDS

LOWER RESPIRATORY TRACT Larynx Trachea Bronchi Lungs

THE TRACHEA Descends into the mediastinum C-shaped cartilage rings keep airway open Carina - marks where trachea divides into two primary bronchi Epithelium - pseudostratified ciliated columnar

BRONCHI Bronchial tree - extensively branching respiratory passageways Primary bronchi (main bronchi) Largest bronchi Right main bronchi - wider and shorter than the left Secondary (lobar) bronchi Three on the right Two on the left Tertiary (segmental) bronchi - branch into each lung segment Bronchioles - little bronchi, less than 1 mm in diameter Terminal bronchioles - less than 0.5 mm in diameter Lead to the structures of the respiratory zone, where gas exchange takes place.

THE LUNGS Extend from diaphragm to the clavicles Divided into lobes by fissures. Right lung has three lobes Left lung has two lobes Concavity on medial surface = cardiac notch Bronchi enter the lungs at the hilus

THE PLEURAE A double-layered sac surrounding each lung Parietal pleura - outer membrane Visceral pleura inner membrane - adheres to the lungs. Pleural cavity - potential space between the visceral and parietal pleurae Pleurae help divide the thoracic cavity Central mediastinum Two lateral pleural compartments

STRUCTURES OF THE RESPIRATORY ZONE Consists of air-exchanging structures Respiratory bronchioles branch from terminal bronchioles Lead to alveolar ducts Lead to alveolar sacs

THE DIAPHRAGM Contraction of Diaphragm inspiration Relaxation of Diaphragm - expiration

LUNG CAPACITY

Questions Complied by: D. Leonard Learning Specialist The Academic Support Center @ Daytona State College http://www.daytonastate.edu/asc/ascsciencehandouts.html