3 Osmosis in Celery Lab

Lab: Osmosis in Celery

Notice: Start this lab when you know you will be able to check on it every 30 minutes for 4 or 5 hours.

Problem: Do Celery Stalks Take In Water?

Hypothesis: If cut celery stalks are placed into water, then water will go into the celery by the process of osmosis.

To easily see whether or not water goes into the celery, this experiment uses colored water. If the color is visible in the celery then water has entered the plant’s cells.

Materials: 1 clear container (plastic water bottle works) Food coloring, red or blue 4 freshly cut stalks of celery (as close to the same size as possible) 1 kitchen knife Optional: Small magnifying lens if available Timer of clock Ruler or meter stick

Caution: Using sharp instrument;You may wish to have an adult assist you with the cuts.

Procedure:

1. Fill the container about 3/4th full. 2. Add about ½ tsp of food coloring to the water. 3. Carefully cut about one inch off of the bottom end of each stalk. 4. Quickly place celery stalks into the colored water. 5. Set the container in a place where it will receive indirect sunlight. 6. Check the stalks every 30 minutes and record observations. 7. Remove one stalk of celery after two hours. 8. Cut about one inch off the bottom of the stalk. 9. Look carefully at the freshly cut sides of the stalk. Use a magnifying lens if possible.

Data (Results) 10. Create a table in which to record your observations. 11. Answer the following questions in a Word document along with your table and upload to your dropbox.

Questions: 1. What is osmosis? 2. Celery is composed of millions of plant cells. Do these cells contain any water? 3. Did the cut celery in step 8 & 9 show any color change that would indicate that the water did enter the celery cells? 4. If you placed the celery into a bottle of colored water that was 35% sugar, would the colored water be seen in the celery? Why or why not?

Graded Assignment:

Submit your completed work to the dropbox labeled: “Osmosis in Celery”