Lecture Notes: The Respiratory System & Fluid Dynamics
Understanding Fluid Types
- Types of Fluids
- Liquids: e.g., Blood (Cardiovascular System)
- Gases: e.g., Oxygen, Carbon Dioxide (Respiratory System)
The Cardiovascular System
- Composed of the heart and blood vessels
- When blood is added to this system, it is referred to as the Circulatory System
- Heart + Blood Vessels + Blood = Circulatory System
Respiratory System Functions
- Gas Exchange: Oxygen intake & Carbon Dioxide removal
- Carbon Dioxide as Metabolic Waste
- Increases blood acidity (carbonic acid formation)
Blood pH and Homeostasis
- Normal pH Range: 7.35 to 7.45
- Acidosis: pH < 7.35
- Alkalosis: pH > 7.45
Acidosis in Athletes
- Causes:
- Increased CO2 from intense metabolic activity (e.g., marathon running)
- Increased acidity due to high carbonic acid
- Response:
- Hyperventilation to expel CO2 and restore pH
Alkalosis
- Causes: Low CO2 levels in the blood
- Response:
- Hypoventilation to retain CO2 and decrease pH
Types of Respiration
- External Respiration:
- Exchange of gases between the environment and lungs
- Oxygen enters lungs; CO2 exits to the air
- Internal Respiration:
- Exchange of gases between blood and tissues
- Oxygen delivered to tissues; CO2 removed from tissues
Principles of Diffusion & Pressure Gradients
- Diffusion: Movement from high to low concentration (applies to gases, heat, etc.)
- Pressure Gradient in Respiratory System:
- Air (highest pressure) → Lungs → Tissues (lowest pressure)
Gas Exchange Dynamics
- Oxygen:
- Highest partial pressure in atmosphere, lowest in tissues
- Carbon Dioxide:
- Highest partial pressure in tissues, lowest in atmosphere
Boyle's Law in Respiration
- Principle: At constant temperature, volume and pressure have an inverse relationship
- Inhalation: Lung volume increases, pressure decreases, air flows in
- Exhalation: Lung volume decreases, pressure increases, air flows out
Anatomy of the Respiratory System
- Trachea: Main airway leading to lungs, composed of cartilage
- Lungs:
- Right Lung: Divided into lobes by fissures
- Left Lung: Fewer lobes, distinguishable by fewer fissures
These notes summarize the key concepts discussed in the lecture on the respiratory system and its interaction with cardiovascular functions, focusing on the dynamics of fluid exchange, especially gases, and how various physiological processes maintain homeostasis in the body.