What is diffusion?
The movement of particles from low concentration to high concentration.
The movement of particles from high concentration to low concentration.
Active movement of particles, requiring energy from respiration.
Which process is responsible for gas exchange in the lungs?
Diffusion
Osmosis
Active transport
What happens to the rate of diffusion as the temperature increases?
What happens to the rate of diffusion as the surface area increases?
What have multi-celled organisms developed in order to provide an increased surface area for gas exchange?
Why do large multicellular organisms need transport systems while simple unicellular organisms do not?
Large organisms have a much smaller surface area to volume ratio compared to smaller ones.
Diffusion does not work in large multicellular organisms.
Unicellular organisms have a much smaller surface area to volume ratio than multicellular organisms.