gas exchange in animals

Subdecks (1)

Cards (9)

  • simple organisms do not require specialised gas exchange system

    Because they can exchange gases across the body surface
  • Skin
    • earthworms use their skin as a gas exchange surface
    • they have blood vessels very close to the surface of the skin
    • they ensure that their skin is moist to aid the diffusion of gases
  • tracheal system
    • insects use this system, as they have an exoskeleton that prevents them from being able to use their skin as a gas exchange surface
    • they have opening in their exoskeleton called spiracles
  • How spiracles work
    • oxygen enters the organism through the mouth or the spiracles and travels through the tracheoles to the cells.
    • carbon dioxide is also removed through the spiracles via diffusion
    • this is often aided by rhymical movements of the abdomen or thorax