respiratory system function

*        Primary Function

▪        Provide O₂ for tissue metabolism &remove CO₂

*        Secondary Functions

§   Sense of Smell

§   Speech Production

§   Fluid Balance

§   Acid Base Balance

§   Thermoregulation

Upper Respiratory Tract: structures

nose

Sinuses

Oral cavity

pharynx

larynx

trachea

mainstem bronchi

bronchioles

alveoli

vocal cords

contains the epiglottis 

closes during swallowing; preventing food entering the tracheobronchial tree

opens during breathing and coughing 

§   Enhances speech sounds

§   Eustachian tube connects nasopharynx with middle ear and opens during swallowing to equalize pressure within the middle ear

*        Mainstem Bronchi

§   Two main stem bronchi

ü  R slightly shorter, wider, and more vertical than L– aspiration more likely to occur in R bronchi

*        Alveoli

§   Total surface area for gas exchange size of tennis court

§   Thin walled air sacs surrounded by a network of capillaries

§   O₂ diffuses into the internal environment and CO₂ diffuses out

§   Composed of 2 types of alveolar cells

ü  Type I cells provide structure

ü  Type II cells secrete Surfactant – which reduces surface tension and contributes to the elastic properties of lungs.

Diaphragm

 External Intercostals

  Abdominal Muscles

Scalene

 Trapezius and Pectoralis Muscles

 Sternocleidomastoids