Solved by a verified expert:Experiment 1: Tonicity and the Animal CellIn this experiment you will explore the effects of osmosis on eggs. An egg is surroundedby a permeable membrane and a hard shell. To observe the effects of osmosis the shellwill first need to be removed.MaterialsAcetic Acid (Vinegar)4 Pieces of Aluminum Foil (to coverbeakers)(4) 100 mL Beakers*Distilled water*4 Eggs10 mL Graduated Cylinder100 mL Graduated Cylinder100% Sugar Solution (Corn Syrup)Stirring Rod*You Must ProvideNote: This lab requires at least one day to prep and at least one day for observations. Forbest results, please use a medium or large sized egg. Jumbo or extra large eggs are toolarge for the experimental set-up.Procedure:1. Set out four beakers with one egg in each beaker.Note: Always wear gloves when handling raw eggs.2. Cover each egg with acetic acid (vinegar).3. Cover each beaker with a piece of foil and allow the eggs to sit for 24 hours.Keep foil for entire experiment. You will need itlater in the experiment.4. You will be placing eggs (cells) in differenttonicities and observing the results. Develop ahypothesis and record it in the data section forthis experiment.© 2013 eScience Labs, LLC.All Rights ReservedFigure 2: An egg that h as beensoaked in vinegar and rinsed withwater. Some white shell remains. 5. After 24 hours, check to see if the egg shell is dissolved by gently taking out eachegg and rinsing with a small amount of water. The eggs should have a yellow tintto them and you should be able to lightly squish the egg between your fingers(Figure 2). BE CAREFUL TO NOT BREAK THE EGG.6. If any of the eggs still have a hard shell after 24 hours allow the eggs to sit foranother 12 – 24 hours.7. Once the egg shells have been dissolved remove them from the vinegar. HANDLEEGGS CAREFULLY. THEY CAN EASILY BREAK.8. Rinse out and dry all four beakers.9. Label one beaker 100 % distilled water, one 100% corn syrup solution, one10% corn syrup/90% water solution and one control.10. In the beaker labeled 10% corn syrup/90% water solution, prepare a 10% sugarsolution by mixing 45 mL of distilled water with 5 mL of corn syrup. Mix well witha stirring rod. Record the initial volume in Table 1.11. In the beaker labeled distilled water, measure and pour 50 mL of distilledwater. Record the volume in Table 1. The egg should be covered. Add or reducethe amount of water if necessary. Record the initial volume in Table 1.12. In the beaker labeled 100% corn syrup solution, measure and pour 50 mL ofcorn syrup (100% sugar solution). The egg should be covered. Add more cornsyrup if necessary. Record the initial volume of the solution in Table 1.13. In the beaker labeled control, do not add any solution. Record the volume inTable 1.14. Add one egg to each beaker and cover with foil.15. Let the eggs sit for 24 hours. In the meantime, develop a hypothesis stating howyou believe each egg will be affected by the solution in the beaker over the 24hour period. Record your hypothesis in the Post-Lab Questions section.16. After 24 hours have passed, observe the eggs. If you do not see any noticeabledifference let the eggs sit for another 12 – 24 hours.17. After the eggs have rested for 24-48 hours in the solutions carefully remove themfrom the beakers. Make sure to note which eggs came from each beaker. Becareful to not spill the solutions.18. Record the final volume of each solution using a graduated cylinder and recordyour results in Table 1.© 2013 eScience Labs, LLC.All Rights Reserved 19. Observe the eggs. Draw your observations in the in Table 2 of data section.DataHypothesis:Table 1: Osmosis ResultsVolume (mL) BeforeOsmosisSolution TypeVolume (mL) AfterOsmosis100% distilled water100% corn syrup10% corn syrup/ 90% distilled watercontrolTable 2: Observations of Eggs After Osmosis100% Distilled Water100% Corn Syrup10% Corn syrup/ 90%Distilled WaterControlPost-Lab Questions1. Record your hypothesis from Step 15 here. Be sure to include scientific reasoningto support your predictions.2. How do each of the three eggs placed in solution compare to the control egg?© 2013 eScience Labs, LLC.All Rights Reserved 3. For each beaker, identify whether the solution inside was hypotonic, hypertonic,or isotonic in comparison to the control beaker.4. What was the direction of osmosis in the beaker labeled 100% distilled water?Did the egg in this beaker burst?5. Was there a volume in the control beaker after 24-48 hours? If so, why do youthink this is? If not, why do you think this is?6. Which solution contained a dehydrated cell? Think about someone having a highsugar diet. Hypothesize how their cells might be affected by osmosis?7. Osmosis is how excess salts that accumulate in cells are transferred to the bloodstream so they can be removed from the body. Explain how this process works interms of tonicity.© 2013 eScience Labs, LLC.All Rights Reserved
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