Respiratory System
Topic Outline: Structure Function Control of breathing Pathologies
Structure of the
Mucous secreting cells
“Goblet Cells”
Look closely at the cells of the alveolus.
Surfactant water tension in the alveolus
Water tension
Diseases & gas exchange:
Emphysema
Fibrotic Lung
Pulmonary edema
Asthma
Compliance (easy to stretch) versus elastance
Pressure and Ventilation
1
2
Helps us understand how air gets in and out of the lungs.
Important Functions of Respiratory System
Oxygen (O2) and Carbon Dioxide (CO2) Transport and Exchange
To the board!
One more time!
Breathing and Control of Respiration
Why does air move in and out of our lungs?
Lung volumes change with muscle contraction
Multiple Muscles of the Thoracic cavityassist us in breathing.
What happens if you puncture your lung?
Lung Volumes Measurement
The amount of air we breathe can be measured
How much air we breathe depends on many factors…
For example: Oxygen binding to Hb
A well studied curve
Oxygen Affinity Decreases for Hb as
Body temperature increases
pH decreases
CO2 increases
DPG increases
Now look at the curves!
Regulation of Ventilation
The mid-brain gets messages from
Aortic bodies
Carotid bodies
Peripheral chemo-receptors
Both of these are
Sensitive to O2, CO2 and pH
Hypothetical Peripheral receptor
Peripheral chemo-receptors talk to central neurons
Central Pattern Generator(medulla oblongata)
Dorsal Regulatory Group Ventral Regulatory Group
Inspiratory neurons Active inspiratory neurons &Active Expiratory neurons
The brain also has its own chemoreceptors also in the medulla.
Summary of ventilation control
Oh, no!
Normal and Diseased LungEmphysema
Pneumonia
Lung CancerLung cancer is responsible for the most cancer deaths in both men and women throughout the world. The American Cancer Society estimates that 173,770 new cases of lung cancer in the U.S. will be diagnosed and 160,440 deaths due to lung cancer will occur in 2004.
Normal Lungs Lung Cancer
Risk Factors
Air pollutionHigh risk occupations
Asbestos Radon Gas
Types of Lung Cancer
Small Cell Lung Cancer
Non-Small Cell Lung Cancer
Adenocarcinomas Squamous cell carinomas Large cell carcinoma
Treatment & Prevention
Prevention is the key decreasing the number of lung cancer patients.
Treatment may include: (not all types of lung cancer respond equally to treatment regimes)
Radiation therapy Surgery Chemotherapy
Treatment is often difficult and may not be successful.