RESPIRATORY SYSTEM BASIC STRUCTURE ANDFUNCTION

OVERVIEW  BASIC STRUCTURE –NOSE, MOUTH & PHARYNX –LARYNX, VOCAL CHORDS –TRACHEA –BRONCHI AND BRONCHIOLE TREE –ALVEOLI  BASIC FUNCTION –GAS EXCHANGE  External Respiration – breathing; ventilation  Internal Respiration – gas exchange at alveoli  Cellular Respiration – exchange at tissue capillary beds –Other Functions:  Clean and moisten air  Excretory  Regulate blood pH ORG. OF RESP. SYSTEM GAS EX

Organs of Respiratory System: Upper Respiratory  Nasal and oral cavities –Incoming air  moisten and warm –1 st line of defense – nose hairs  Filter  External nares –2 nd line of defense – mucus  Goblet cells  Sticky glycoprotein  Sinuses  Pharynx – muscular, mucus producing connecting tube –Nasophayrnx, oropharynx, laryngopharynx –Common to both respiratory and digestive systems PHARYNX

Organs of Respiratory System: Upper Respiratory  Larynx –Opening to respiratory only passage  Glottis –Epiglottis – prevents solid/liquid particles from entering –Major cartilages: thyroid, cricoid, epiglottic, arytenoid, corniculate, cuneiform –Vocal Cords – produce sound  False – upper; help with swallowing/ close trachea  True – flaps of vibrating tissue –Pitch – frequency; tautness –Intensity – amplitude; loudness LARYNX STRCT LARYNX PHOTO

Organs of Respiratory System: Lower Respiratory  Lower Respiratory – in thorax  Trachea – windpipe –Anterior to esophagus –C-Shaped rings  About 20  Flexible in back for peristalsis  Mucus –Cilia  Beating toward larynx  Trapped micros swallowed + digested

Organs of Respiratory System: Lower Respiratory  Bronchial Tree –Bronchus – L & R  1 o, 2 o, 3 o –Bronchioles  Intralobular, terminal, respiratory –Alveolar ducts  Alveolar sacs  ALVEOLI  Microscopic air sacs surrounded by capillaries  Gas Exchange – diffusion –Trends  Less cartilage, smaller diamers, less mucus  Psuedostratified Columnar  simple squamous ALVEOLAR GAS EX DIAGRAM

LUNGS  Encases bronchiole tree  Right – 3 Lobes; Left – 2 Lobes  Hilus – indented opening –Medial side –Blood vessels, nerves and Bronchi  Membranes –Visceral Pleura –Parietal Pleura –Pleural Cavity  Potential space  Serous fluid  Surface Tension

Organs of Respiratory System

Gas Exchange

PHARYNX

LARYNX STRUCTURE

LARYNX

BRONCHIOLE TREE

Gas Exchange at Alveoli