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

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

4. Cellular Respiration
O2 needed in conversion of glucose to cellular energy (ATP) in all body cells
Carbon dioxide (CO2) is produced as a waste product
The body’s cells die if either the respiratory or cardiovascular system fails = NO ATP!

5. Human Respiratory System
Figure 10.1

6. 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

7. Structures of Thoracic Cavity
Cartilage rings support
pressure
from breathing & maintain
open pathways of trachea
and bronchi
Pleural membranes(2) –fluid filled to reduce friction from movement
Smooth muscle
that relaxes
and contracts
(absence of cartilage)
Figure 10.3

10. Bronchial tree (Bronchi)
Right main bronchus
Each bronchus runs into a lung, behind pulmonary vessels (pulmonary artery/vein from heart)

11. Bronchial
“tree” and
associated
Pulmonary
arteries

12. p. 188 in your book!

13. Trachea and Bronchi lined with Respiratory Mucosa
Ciliated epithelium
Scattered goblet cells – produce mucin (mucus) and watery fluid
Macrophages - digestive enzymes, e.g. lysozyme
Together all these produce a quart/day
Dead junk is swallowed

15. smaller tubes, tubes smaller than 1 mm called bronchioles
Bronchi divide into
smaller tubes, tubes smaller
than 1 mm called bronchioles
Brochioles: tissue changes as becomes smaller
Cartilage disappears
No mucus or cilia in tissue of cells
Smooth muscle - relaxation (“bronchodilation”) and contraction (“bronchoconstriction”)

16. Alveoli End-point of respiratory tree
Structures that contain air-exchange chambers are called alveoli
Respiratory bronchioles lead into alveolar ducts: walls consist of alveoli
Ducts lead into terminal clusters called alveolar sacs – are microscopic chambers
There are 3 million alveoli!
Alveoli

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

19. Microscopic detail of alveoli
Single layer thick- diffusion
surrounded by fine elastic fibers
Alveolar macrophages – free floating “dust cells”

20. Respiratory Cycle
Figure 10.9

21. Smoking and Human Health
Threats:
Tar and carcinogens
Carbon monoxide
nicotine
Passive smoking (2nd hand smoke)- breathing someone else’s smoke
Atmospheric pollution and industrial emissions – lead to respiratory diseases

22. Chronic (long term) obstructive pulmonary diseases (COPD)
Asthma
Chronic bronchitis
Emphysema

23. SEM image of alveoli
normal
emphysema

24. Chronic bronchitis - Tar stimulates goblet cells
Destroys cilia; bacteria & viruses collect
Smoker’s cough; pneumonia

26. Emphysema
Inflammation of constantly infected lung causes phagocytes (white blood cells) to leave blood and line airways
Release elastase which destroys elastin walls of alveoli (can’t stretch/recoil)
Air is trapped, alveoli can burst
Reduces surface area for gas exchange – less O2 in blood
Wheezing, breathlessness,
Heart enlargement

28. Lung Capacity
Figure 10.10A

29. Collapsed Lung

30. Lung Cancer
Substances in tobacco smoke produce mutations in DNA of lung epithelial cells lose control of cell reproduction tumor
Tumor can spread through lymphatic system and other parts of body = metastasis
Coughing up blood = tissue damage

31. Smoker’s lung

32. 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 (macrophages attack and destroy elastin)
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

33. E-Cigarettes (vapes)