Laboratory Investigation:

Gummy Candy Osmosis Lab

Background:(Use the words in the word bank to complete the paragraphs below)

water
membrane
lower / cells
selectively permeable / inside
outside / osmosis
higher

Organisms are made up of tiny living units called ______. Each cell is surrounded by a ______that protects the cell by keeping the cell parts inside and keeping other things outside. While it stops most things, ______can pass through it. We call the membrane ______, because it decides what comes in and out.

______is the diffusion of water. When osmosis occurs, water molecules move from a ______concentration of water towards a ______concentration of water. If the water outside the cell is LESS concentrated than inside, water will move from the ______of the cell to the ______.

Objectives:

  • Use the concept of diffusion/osmosis to increase or decrease the size of a gummy candy.
  • Given a list of materials, design an experimental set up that will be used to increase or decrease the size of a gummy candy.

Materials Available:

Gummy candiesRulers Tap Water

Plastic cupsTriple Beam Balance Salt Water

Paper towels Distilled water

Your Task:

There are three different tasks your group may choose from. In the space below, state the task your group has chosen. Then predict how you can accomplish it using the concept of osmosis and the materials above (this is your hypothesis).

Designing Your Experiment:

Identify the variables of your experiment.

  • Independent Variable: ______
  • Dependent Variable: ______
  • How will you measure this? Be Specific!

In the space below, write a step by step procedure your group will use to set up your experiment. Be detailed! Another person should be able to read this procedure and carry out this experiment exactly as your group will.

When you feel your procedure is complete, raise your hand and have it checked by your teacher. If your teacher approves your directions and initials the box at the bottom of this paper you may gather your materials and carry out your procedure for day 1.

Day 1 – Set up

Day 2 – Observations

Results:

In the space below create a data table where you will record your before and after measurements.

Analysis:

  1. Did your group accomplish your task? Use data from your results to support your answer.
  1. Find another group that carried out the same task. Did they have similar results? If yes, did you use a similar set up? If no, why do you think your results were different?

Regents Questions:

  1. Which percentage would explain the net movement of water into a cell through the process of osmosis?

A) water was 90% inside the cell and 95% outsideC) water was 95% inside the cell and 90% outside

B) protein was 30% inside the cell and 35% outside D) water and protein was equal inside and outside

  1. Food is often treated to lower the risk of disease and spoilage, as shown in the chart below.

Explain why high salt concentrations can kill organisms.