ANATOMY & PHYSIOLOGY

Respiratory System

Functions of the Respiratory System

Gas Exchange

Organs of the Respiratory System

Upper Respiratory Tract Nose Pharynx Larynx

Lower Respiratory Tract Trachea Bronchi Lungs

Nose

framework composed of bone & cartilage2 nostrils called: external nares

where air enters the nasal cavity rt & lt separated by nasal septum

site of nose bleeds@ internal edge: internal nares

Pharynx

throat 3 divisions:1. Nasopharynx

begins @ internal nares end of soft palate

2. Oropharynx edge of soft palate hyoid bone

3. Laryngopharynx hyoid bone upper edge of esophagus

3 Parts of the Pharynx

Larynx

“voice box”CartilageParts:

Epiglottis Glottis Thyroid cartilage Cricoid cartilage

Larynx

moves upward when you swallow tips epiglottis over the glottis (opening of

trachea) allows food esophagus (--/ down trachea to

lungs) if not swallowing: glottis is open allowing air

lungs

http://www.linkstudio.info/images/portfolio/medani/Swallow.swf

Trachea

“windpipe”

Trachea

rings of cartilage maintain its shape to prevent it from closing

forks into 2 bronchi

Bronchus

each enters a lung where it branches into smaller & smaller bronchioles resembling an inverted tree

Bronchioles

fine tubes that allow passage of airsmooth muscle surrounds them when

contracts airways constrictepithelium covered with cilia & mucus

mucus traps dust, particulates cilia beat upward removing trapped particles

from airways (moves particles ~1-3 cm/hr)

Bronchioles

Gas Exchange in Lungs

Gas Exchange in Lungs

Pulmonary Function Tests

“PFTs”subject breathes into a closed system in

which air is trapped w/in a bell floating in water

bell moves up when patient exhales / down when they inhale

Pulmonary Function Tests

Tidal Volume: amt of air expired

Vital Capacity: max amt of air that

can forcefully exhaled after a max inhalation

Spirogram

Anatomical Dead Space

not all inspired air will get into lungs exhaling does not force all air out of the

body

Hemoglobin

helps transport oxygen, carbon dioxide, & buffer blood

as carbon dioxide leaves cells & diffuses thru interstial fluid then into capillary it combines with water to form carbonic acid

Hgb Loading & Unloading Oxygen

Respiratory pH Balance

Respiratory Acidosis

hypoventilation accumulation of CO2

in tissuespH decreasesplasma HCO3-

increases

Respiratory Alkalosis

hyperventilationexcessive loss of CO2pH increasesplasma HCO3-

decreasesCO2 in blood

increases