Eastern Intermediate High School
Honors Biology
Name:___________________________
Mod:___________ Date:____________
Unit 7 – The Plasma Membrane, Transport and Homeostasis
Lab – Observing Osmosis in Carrots
Objective: To observe osmosis on a macroscopic level.
Materials:
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2 Baby Carrots
String
Scissors
Salt Water Solution
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2 beakers
1 digital scale
Paper Towels
Procedure:
1. Download and save a copy of this file into the correct folder on the shared drive. Data will be recorded directly on
this document. The file name should read – “Your Last Names . Carrot Lab . Class Period.doc”
2. Label two beakers as #1 and #2. Be sure to write your group name or number on the beakers as well.
3. Obtain two baby carrots from the back of the room and measure the mass of each carrot and record the data.
4. Measure the length of each carrot to the nearest millimeter and record these measurements in your data table.
5. Tie a piece of string firmly around each baby carrot.
6. Fill Beaker #1 halfway with distilled water and then fill Beaker #2 halfway with salt water.
7. Place one carrot in Beaker #1, the other in a Beaker #2.
8. Observe the carrots and record qualitative observations in your data table.
9. After a few days, observe the carrots and record your final qualitative and quantitative observations in your data
tables.
Data:
Beaker #1
Contents:
dH2O
Initial Quantitative Observations
Mass:
Initial Qualitative Observations
Carrot:
String:
Length:
Water:
Final Quantitative Observations
Mass:
Final Qualitative Observations
Carrot:
String:
Length:
Water:
1
Beaker #2
Contents:
Salt H2O
Initial Quantitative Observations
Mass:
Length:
Initial Qualitative Observations
Carrot:
String:
Water:
Final Quantitative Observations
Mass:
Final Qualitative Observations
Carrot:
String:
Length:
Water:
Analysis Questions: Answer should be in Complete Sentences where needed. Submit your final
answers via the Google Student Response Sheet.
1. Compare the change in the masses of the carrots in each beaker. (Did their masses both increase,
decrease, stay the same, explain)
2. Compare the change in the length of the carrots in each beaker. (Did their lengths both increase,
decrease, stay the same, explain)
3. Compared to your initial observations, what qualitative changes did you observe in your final
observation of the strings?
4. What does the string tell us about the changes in the size and shapes of the carrot cells?
5. What is osmosis?
6. Why did the size and shape of the carrot cells change in each beaker? Describe both beakers and use the
terms isotonic, hypotonic, or hypertonic in your answer.
7. Based on what you have learned so far, why can gargling salt water help people suffering from a sore
throat? Use the terms isotonic, hypotonic, or hypertonic in your answer.
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