Diffusion and Osmosis
1. For each of the following sentences, indicate whether the process involved is
diffusion or osmosis.
diffusion
osmosis
Oxygen crosses the alveoli of the lungs and enters the blood
Water enters the guard cells in leaves from surrounding cells
Water moves from the mouth to the drier atmosphere
Water enters blood capillaries from the surrounding body cells
Water in the soil crosses into the root hairs of plants
Water is absorbed out of the kidney tubules and back into the
bloodstream
In the blood vessels in the lungs, oxygen enters the red blood cells
Carbon dioxide enters the stomata (pores) in leaves for
photosynthesis
2. Kelly set up an experiment. She placed one prune in a beaker of distilled water
and another in a very strong sugar solution (syrup).
a) Kelly returned to her experiment 24 hours later.
b) Explain what you would expect to have happened to Prune A and Prune B.
3. Joseph’s mother showed him how she makes a fruit salad.
She cut fruit up and put the pieces into a bowl. She then
sprinkled sugar all over the fruit. She placed the bowl in
the fridge overnight. When she took the bowl out the
following day, Joseph noticed that the fruit had liquid all
around it.
His mother then placed a few drops of food colouring in the middle of the bowl
and again returned it to the fridge.
a) What is the liquid in the bowl and where did it come from?
b) By what process did the liquid appear in the bowl?
c) Later that day Joseph noticed that the food colouring had spread through
the liquid. What process had occurred?