Name:______________________________        Hr:_____________        Date:__________

Lab: It’s in the Bag

Define Exocytosis:

Define Endocytosis:

Purpose:

A cell is a membrane filled with liquid, much like a water balloon. Food or large particles can be taken into and released from the cell without bursting. We will demonstrate how a cell is able to perform this function without bursting.

Materials:

• Fun sized candy bar
• Plastic bag
• String
• Scissors

Directions:

1. The plastic bag represents the cell.
2. The candy bar sitting on the table top represents food needed by the cell to carry out respiration and produce the ATP energy needed by the cell to survive.
3. Your objective is to bring the candy into the plastic bag without making a hole in the bag.
4. Your hands must be kept inside the bag at all times.
5. Carefully place a pair of scissors and string inside of the bag.
6. Insert your hands inside the plastic bag and keep them in the bag from this point forward.
7. Cut a small length of strong into two pieces. With your hand still inside the bag, close your hand around the piece of candy. (This should form a pouch enclosing the candy within the bag.)
8. Tightly tie off the neck of the pouch with one string.
9. Using the second piece of string, tie off the neck of the pouch about 2 cm away from the first string.
10. Use the scissors to cut the bag between the two strings you have tied in place.

Questions:

1. What is the process that you just demonstrated called?

2. Why does the cell use this process?

3. Explain the difference between endocytosis and exocytosis.