Animal Transport Systems

• Why do organisms need transport systems?

  To accommodate larger size and higher metabolic rates
• What is a consequence of a smaller surface area to volume ratio in organisms?

  It necessitates the need for a transport system
• What are the features of a good transport system?

  A fluid, a pump, exchange surfaces, and tubes or vessels
• What type of circulation do insects and molluscs have?

  Open circulation
• How does open circulation function in certain animals?

  The heart promotes circulation of haemolymph within the body cavity
• What type of circulation do mammals, birds, and fish have?

  Closed circulation
• What is the role of tissue fluid in closed circulation?

  It bathes the cells while blood travels in closed vessels
• What is an advantage of closed circulation?

  It allows for quick pumping of fluid, oxygen, and nutrients
• What distinguishes single circulatory systems from double circulatory systems?

  Single systems pump blood to the exchange surface and then to the body, while double systems pump blood to the exchange surface and back to the heart
• In a single circulatory system, what limits blood pressure?

  The delicate nature of capillaries in the exchange surface
• How does a double circulatory system benefit an organism's activity level?

  It allows for higher blood pressure in the systemic circuit, enabling faster delivery to respiring tissues
• What are the key components of a good transport system?

  • A fluid to carry nutrients and oxygen
  • A pump to create pressure
  • Exchange surfaces for gas and nutrient exchange
  • Tubes or vessels for fluid movement
• What are the differences between single and double circulatory systems?

  Single Circulatory System:

  • Blood passes through the heart once per circuit
  • Example: Fish

  
  

  Double Circulatory System:

  • Blood passes through the heart twice per circuit
  • Includes pulmonary and systemic circuits
  • Example: Mammals and birds
• Compare open and closed circulatory systems.

  Open Circulation:

  • Fluid (haemolymph) not enclosed in vessels
  • Found in insects and molluscs

  
  

  Closed Circulation:

  • Blood enclosed in vessels
  • Found in mammals, birds, and fish
  • Allows for efficient nutrient and oxygen transport