Week 12

Key Concepts and Terms

Chapter 42.1: The Respiratory and Circulatory Systems

• Ventilation: The process of moving air in and out of the lungs.

• Gas Exchange: The process of obtaining oxygen and eliminating carbon dioxide.

• Circulation: The movement of blood through the heart and around the body.

• Cellular Respiration: The metabolic process where cells convert glucose and oxygen into energy, producing CO2 as a byproduct.

• Respiratory System: The organ system responsible for gas exchange.

Topics and Units Overview

Units Overview

• Weeks 9-12: Focus on cellular interactions, genetics, reproduction, and gas exchange.

• Week 12: Intensively covers gas exchange and circulation from April 14-18.

• Exams: Exam 3 scheduled for April 21-24, covering Chapter 42.

Chapter 42.2: Air and Water as Respiratory Media

• Partial Pressures of Gases: Understanding Dalton’s Law is crucial for gas exchange comprehension.

• Factors Influencing Gas Exchange:

  • Solubility of gases in air and water.

  • Oxygen levels in aquatic vs. terrestrial environments (greater challenge for aquatic organisms).

• Learning Outcomes:

  • Calculate partial pressure and explain gas diffusion at different altitudes.

  • Discuss how physical factors impact gas solubility in water.

Chapter 42.3: Organs of Gas Exchange

• Surface Area-to-Volume Ratio: Larger organisms require specialized structures (e.g., lungs) for efficient gas exchange.

• Fick’s Law of Diffusion: Understand the relationship between variables affecting gas diffusion.

• Gas Exchange Organs: Gills, tracheae (insects), and lungs described in detail.

• Ventilation Types:

  • Positive Pressure Ventilation

  • Negative Pressure Ventilation

• Learning Outcomes:

  • Discuss metabolic impacts on gas exchange efficiency based on Fick’s law.

  • Diagram the countercurrent exchange system for enhanced gas exchange.

  • Compare respiratory methods across gills, tracheae, and lungs.

Chapter 42.4: Gas Transportation in Blood

• Blood Composition:

  • Plasma: Liquid component.

  • Formed Elements: Platelets, white blood cells, red blood cells (RBCs).

• Hemoglobin: Structure and function in oxygen transport.

  • Cooperative Binding: How it influences oxygen saturation.

  • Bohr Shift: Significance for homeostasis under varying pH conditions.

• Learning Outcomes:

  • Explain hemoglobin's role in oxygen transport and how it responds to physiological demands.

  • Compare and contrast oxygen loading/unloading mechanisms in different conditions.

Chapter 42.5: Circulation

• Types of Circulatory Systems:

  • Open vs. Closed Circulatory Systems: Key differences in structure and function.

  • Heart Anatomy: Description of atria and ventricles, specifics of pulmonary and systemic circulation.

• Hydrostatic vs. Osmotic Pressure: Understanding fluid movement in capillary beds.

• Learning Outcomes:

  • Describe basic blood circulation pathways and changes in oxygen and carbon dioxide partial pressures.

  • Detail the factors affecting blood pressure and its implications on circulation efficiency.

Ideas for Consideration

• Interactions between respiratory and circulatory systems for gas transport.

• Environmental effects and cellular metabolism variations impacting gas exchange.

• Advantages of circulatory system adaptations in terrestrial vertebrates versus aquatic organisms.

• Dynamic control of blood flow and the importance of muscle structures in circulation.

Study Figures

• Review figures 42.1 through 42.6 to visualize key concepts in gas exchange and circulation.

• Pay particular attention to diagrams illustrating Fick’s law, countercurrent exchange mechanisms, and the structure of hemoglobin.