No energy required

Substances move against

the concentration

gradient

Requires carrier proteins

in the membrane

Movement of substances

Occurs over a membrane

Requires a partially

permeable membrane

Requires energy

Substances move down a

concentration gradient

Water moves down a

concentration gradient

No membrane required

Diffusion Osmosis

Active

Transport Comparing Diffusion, Osmosis,

and Active Transport

Stretch Task: Can you think of

anything else to put in the Venn

diagram?