Observing Osmosis

It is difficult to see osmosis occurring in cells because of the small size of the cell. However, there are a few cells that can be seen without the aid of a microscope. Try this activity to see how osmosis occurs in a large cell.

Problem: How does osmosis occur in an egg cell?

Materials

• Raw egg
• 500 ml beaker
• 250 ml vinegar
• 250 ml corn syrup
• 250 or larger graduated cylinder
• parafilm (or saran wrap)
• water

Day 1

____ Place the egg into the 500 ml beaker. Pour 250 ml of vinegar over the egg. Cover the beaker

____ After 30 minutes, record your observations in the data table

____ Let stand for two days

Day 2

____ Record the appearance of the egg in the data table.

____ Carefully pour the vinegar into a graduated cylinder, record the amount you now have in the data table.

____ Rinse the egg off and pour 250 ml of the corn syrup over the egg and cover. Let stand for two days.

Day 5

____ Record the appearance of the egg in the data table.

____ Carefully pour the corn syrup into a graduated cylinder. Record the amount in the data table.

____ Rinse off the egg and pour 250 ml of water over the egg. Cover and let stand for two days.

Day 7

____ Record the appearance of the egg in the data table

____ Carefully pour the water into a graduated cylinder and record the amount in the data table.

____ Dispose of your egg.

Data Table