1. RESPIRATORY SYSTEM EXCHANGE OF GASES
PowerPoint® Lecture Slide Presentation by Robert J. Sullivan, Marist College
RESPIRATORY SYSTEM
EXCHANGE OF GASES
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings.

2. What is Human Respiration?
The human respiratory system allows one to obtain oxygen, eliminate carbon dioxide.
Breathing consists of two phases, inspiration and expiration
Inspiration- the process of taking in air
Expiration- the process of blowing out air

3. Human Respiratory System
Figure 10.1

4. Organs in the Respiratory System
STRUCTURE
FUNCTION
nose / nasal cavity
 warms, moistens, & filters air as it is inhaled
pharynx (throat)
 passageway for air, leads to trachea
larynx
 the voice box, where vocal chords are located
trachea (windpipe)
 keeps the windpipe "open"  trachea is lined with fine hairs called cilia which filter air before it reaches the lungs
bronchi
 two branches at the end of the trachea, each lead to a lung
bronchioles
 a network of smaller branches leading from the bronchi into the lung tissue & ultimately to air sacs
alveoli
 the functional respiratory units in the lung where gases are exchanged

5. Upper Respiratory Tract

6. Paranasal Sinuses
Four bones of the skull contain paired air spaces called the paranasal sinuses - frontal, ethmoidal, sphenoidal, maxillary
Decrease skull bone weight
Warm, moisten and filter incoming air
Add resonance to voice.
Communicate with the nasal cavity by ducts.
Lined by pseudostratified ciliated columnar epithelium.

7. Paranasal sinuses

8. Pharynx
Common space used by both the respiratory and digestive systems.
Commonly called the throat.
Originates posterior to the nasal and oral cavities and extends inferiorly near the level of the bifurcation of the larynx and esophagus.
Common pathway for both air and food.

9. Pharynx
Walls are lined by a mucosa and contain skeletal muscles that are primarily used for swallowing.
Flexible lateral walls are distensible in order to force swallowed food into the esophagus.
Partitioned into three adjoining regions:
nasopharynx
oropharynx
laryngopharynx

10. Upper Respiratory Tract Functions
Passageway for respiration
Receptors for smell
Filters incoming air to filter larger foreign material
Moistens and warms incoming air
Resonating chambers for voice

11. Components of the Lower Respiratory Tract
Figure 10.3

12. Lower Respiratory Tract
Functions:
Larynx: maintains an open airway, routes food and air appropriately, assists in sound production
Trachea: transports air to and from lungs
Bronchi: branch into lungs
Lungs: transport air to alveoli for gas exchange

13. Larynx Nine c-rings of cartilage form the framework of the larynx
thyroid cartilage – (1) Adam’s apple, hyaline, anterior attachment of vocal folds, testosterone increases size after puberty
cricoid cartilage – (1) ring-shaped, hyaline
arytenoid cartilages – (2) hyaline, posterior attachment of vocal folds, hyaline
cuneiform cartilages - (2) hyaline
corniculate cartlages - (2) hyaline
epiglottis – (1) elastic cartilage

14. Larynx
Muscular walls aid in voice production and the swallowing reflex
Glottis – the superior opening of the larynx
Epiglottis – prevents food and drink from entering airway when swallowing
pseudostratified ciliated columnar epithelium

15. Sound Production Inferior ligaments are called the vocal folds.
- are true vocal cordsﾓbecause they produce sound when air passes between them
Superior ligaments are called the vestibular folds.
- are false vocal cordsﾓbecause they have no function in sound production, but protect the vocal folds.
The tension, length, and position of the vocal folds determine the quality of the sound.

17. Trachea A flexible tube also called windpipe.
Extends through the mediastinum and lies anterior to the esophagus and inferior to the larynx.
Anterior and lateral walls of the trachea supported by 15 to 20 C-shaped tracheal cartilages.
Cartilage rings reinforce and provide rigidity to the tracheal wall to ensure that the trachea remains open at all times
Posterior part of tube lined by trachealis muscle
Lined by ciliated pseudostratified columnar epithelium.

18. Gas Exchange Between the Blood and Alveoli
Figure 10.8A

19. Respiratory Cycle
Figure 10.9

20. Muscles that ASSIST with respiration
The scalenes help increase thoracic cavity dimensions by elevating the first and second ribs during forced inhalation.
The ribs elevate upon contraction of the external intercostals, thereby increasing the transverse dimensions of the thoracic cavity during inhalation.
Contraction of the internal intercostals depresses the ribs, but this only occurs during forced exhalation.
Normal exhalation requires no active muscular effort.

21. Muscles that ASSIST with respiration
Other accessory muscles assist with respiratory activities.
The pectoralis minor, serratus anterior, and sternocleidomastoid help with forced inhalation,
while the abdominal muscles(external and internal obliques, transversus abdominis, and rectus abdominis) assist in active exhalation.

23. Respiratory Values
A normal adult averages 12 breathes per minute = respiratory rate(RR)
Respiratory volumes – determined by using a spirometer

24. LUNG VOLUMES
TIDAL VOLUME (TV): Volume inspired or expired with each normalﾊbreath. = 500 ml
INSPIRATORY RESERVE VOLUME (IRV): Maximum volume that can be inspired over the inspiration of a tidal volume/normal breath. Used during exercise/exertion.=3100 ml
EXPIRATRY RESERVE VOLUME (ERV): Maximal volume that can be expired after the expiration of a tidal volume/normal breath. = 1200 ml
RESIDUAL VOLUME (RV): Volume that remains in the lungs after a maximal expiration.ﾊ CANNOT be measured by spirometry.= 1200 ml

25. http://teachhealthk-12. uthscsa

26. Malfunctions & Diseases of the Respiratory System
asthma
severe allergic reaction characterized by the constriction of bronchioles
 bronchitis
inflammation of the lining of the bronchioles
emphysema
condition in which the alveoli deteriorate, causing the lungs to lose their elasticity
pneumonia
condition in which the alveoli become filled with fluid, preventing the exchange of gases
lung cancer
irregular & uncontrolled growth of tumors in the lung tissue

27. Four Respiration Processes
Breathing (ventilation): air in to and out of lungs
External respiration: gas exchange between air and blood
Internal respiration: gas exchange between blood and tissues
Cellular respiration: oxygen use to produce ATP, carbon dioxide as waste

29. Respiratory mucosa
A layer of pseudostratified ciliated columnar epithelial cells that secrete mucus
Found in nose, sinuses, pharynx, larynx and trachea
Mucus can trap contaminants
Cilia move mucus up towards mouth