1.17 - Specialised Exchange Surfaces

• What is a specialised exchange surface?

  the parts of an organism over which they exchange substances with their environment
• What are common features of specialised exchange surfaces?

  • Large Surface Area

  lots of molecules can diffuse across at the same time

  higher rate of diffusion

  • Exchange surfaces are thin

  short distance to diffuse across

  • Exchange surfaces are permeable

  allow substances to diffuse

  • Good supply of blood (internal medium)
  • Good supply of external medium
• Name examples of specialised exchange surfaces in animals.

  Villi

  Alveoli
• Name examples of specialised exchange surfaces in plants.

  Root hair cells

  Leaves