, Vital substances to be transported
include:
• Oxygen
• Carbon dioxide
• Nutrients
• Waste products
• Hormones
• Disease fighters
, Body size
• Small organisms rely more on diffusion &
therefore do not require a circulatory
system
• Larger organisms cannot survive on
diffusion alone & require circulatory
systems in order to survive
, What about animals with no
transport system?
nutrients
oxygen
Waste
products DIFFUSION Carbon
dioxide
CONCENTRATION GRADIENTS