THE RESPIRATORY SYSTEMChapter 23
Functions
Area of gas exchange between air and circulating blood
Producing sounds for communication
Components of the Respiratory System
Respiratory Defense System Goblet cells and mucous glands
produce a thick mucous to bathe exposed surfaces
This traps foreign particles Cilia “sweep” the mucous and
trapped debris to the pharynx where it will be swallowed, this is called the “mucous elevator”
Mucous production stimulated by exposure to vapors, allergens, pathogens….
Organization of the Respiratory System
2 major divisions Upper
Nose, nasal cavity, paranasal sinuses and pharynx
LowerLarynx, trachea, bronchi, bronchioles and alveoli of lungs
The Upper Respiratory System The Nose and Nasal Cavity Primary entrance for air Enters the external nares or nostrils which
opens up to the nasal cavity Hairs: trap large airborne particles and
prevent from entering the cavity Nasal Septum separates the nasal cavity
into Right/Left halves Superior, Middle, Inferior Nasal Concha
separate into meatuses which cleanse, warm and filter air
Nasopharynx is the junction between the nasal cavity and the Pharynx
The Upper Respiratory System Pharynx Chamber shared by digestive and respiratory
tracts 3 divisions
Nasopharynx Superior portion Connects nasal cavity to the pharynx
Oropharynx Boundary between Nasopharynx and
Oropharynx Laryngopharynx
Entrance of larynx and esophagus
The Lower Respiratory System Larynx
Air leaves the Pharynx and enters the Larynx through the glottis
Made of 3 large pieces of cartilage1. Thyroid Cartilage2. Cricoid Cartilage3. Epiglottis
The Lower Respiratory System Larynx Thyroid Cartilage
Largest Known as the “Adam’s apple”
Cricoid Cartilage Ring shaped Protect the entrance to the trachea
Epiglottis Forms a lid or flap over the glottis of the
Larynx Closes during swallowing prevents food
from entering the lungs
Sound produced at the vocal folds
Trachea
The Lower Respiratory System Laryngeal Problems:
Aspiration: weakening of the epiglottisChoking on foodCommon with elderly
The Lower Respiratory System Trachea
Aka windpipe Starts at the end of the Larynx and
ends at the branching to form the Right and Left Primary Bronchi
Has several tracheal cartilage ringsStiffens to protect airway from collapse or overexpansion
The Lower Respiratory System The Bronchial Tree Primary Bronchi
First branching towards right or left lungs Secondary Bronchi
Branching entering each lung Right lung= 3 Left lung = 2
Tertiary Bronchi 10 additional branching segments in each lung
Bronchioles Multiple passageways connect to alveolar ducts
The lower Respiratory System Alveoli are the structures in which
gas exchange occurs About 150 million per lung Covered with capillaries
Vessels carrying deoxygenated blood transport it to the capillaries found on the alveoli where CO2 is exchanged with O2
Right Lung—3 lobesLeft Lung—2 lobes
Day 2
Pulmonary Ventilation
Physical movement of air into and out of the respiratory tract.
Air moves in and out due to pressure changes
Respiratory Tract
Divided into a conducting portion and a respiratory portion
Conducting portion=from the entrance down to the terminal bronchioles
Respiratory portion=respiratory bronchioles and alveoli
Inhalation (Inspiration)
1. Diaphragm contracts1. Moves down
2. Rib cage relaxes1. Moves out
3. Pressure decreases
4. Air rushes in
Exhalation (Expiration)
1. Diaphragm relaxes1. Moves up
2. Rib cage contracts
1. Moves in
3. Pressure increases
4. Air pushed out
Day 3
http://www.youtube.com/watch?v=mhtArz6fl10&feature=related
Respiration rate
Number of breaths you take each minute
Normal adult resting=12-18 breaths/minute
Children=18-20 breaths/minute
Tidal Volume
Air moves from an area of high pressure lower pressure
1 Respiration cycle: inspiration and expiration Tidal Volume: amount of air moving into
or out of lungs during 1 cycle
Inspiratory Reserve Volume
• Amount of air you can voluntarily inhale after you have completed a normal respiration cycle
Inspiratory Reserve Volume (IRV)
Expiratory Reserve Volume (ERV)
Amount of air you can voluntarily expel after you have completed a normal respiration cycle
Residual Volume
Amount of air that remains in your lungs even after a maximal exhalation
Typical =1200mL in males, 1100mL in females
Vital Capacity
Maximum amount of air you can move into or out of your lungs in 1 single respiration cycle
Total Lung Capacity
Total volume of your lungs Sum of tidal and residual
Typically 6000mL in males, 4200mL in females
Regulation of Breathing
Acidity of your blood increases as the amount of CO2 increases
When you work out your body increases the breathing rates to decrease the amount of acidity
Asthma
http://www.youtube.com/watch?v=S04dci7NTPk&NR=1
Pneumonia
http://www.youtube.com/watch?v=cWQ14x1URXo&feature=related