UNDERSTANDING THE CELL MEMBRANE Single Cell Egg Lab Day 2 UNDERSTANDING THE CELL MEMBRANE

Success Criteria Learning Targets Conduct an investigation to understand the structure and function of cell membranes Conduct the Naked Egg Lab and record data

Overall Guidelines The egg has soaked for 7 days in vinegar to dissolve the shell You will be testing an assigned chemical on your egg. The eggs are very fragile. Handle the egg as little as possible. Use the cup to move it around (not your hand) Wash your hands thoroughly when done handling the egg.

Which solution will have the greatest affect on an egg’s mass? GROUP A Red Drink GROUP B Water GROUP C Ammonia GROUP D Vinegar GROUP E Soapy Water GROUP F Run-off Water GROUP G Salt Water GROUP H Sugar Water GROUP I Motor Oil GROUP J Simple Green

IDENTIFY VARIABLES Treatments/liquids egg soaks in Size (mass) of egg Amt of treatment egg is soaked in, length of time soaking

MAKE A HYPOTHESIS (Choose One Below) The egg will lose mass The egg will gain mass The egg’s mass will stay the same

MATERIALS Deshelled egg Cup Gloves, Apron, Goggles Electronic Balance Ruler Sharpie Assigned Liquid Solution in 2 liter bottle with lid Tape/straw as needed

ACCURATE REPORTING Put your initials on the cup with the sharpie. Add the period number and group letter Add the date & time

PROCEDURES: Obtain a cup from the teacher & measure it’s mass in grams using a balance. Record the beginning cup measurement. 3. Place egg gently in the cup and measure it’s mass with the cup in grams using a balance. Record the total mass of egg plus cup. Subtract step 2 from step 4 and record (This is the egg’s beginning mass). Report the mass to your teacher and verify it is correct. Gently shake the assigned solution by rocking it back and forth in the sealed bottle. Quickly remove the cap and pour it over the top of the egg until completely covered. Use a sharpie to mark the beginning height of the egg. If floating only: Use a straw with tap to hold down the egg. Place the egg in the assigned location Wait for the assigned amount of time directed by your teacher Record observations and drawings (Make sure the data table is correct)

Units? Make before you put it in treatment: What does the egg look like? Feel Like? Do this before you add treatment…

Other ways to use an Electronic Balance Turn on, push the zero button. Place container on the balance. Hit RE- ZERO. This automatically subtracts the weight of the container. Add egg, record mass. Remove both container & egg.

24-48 hours later Locate your egg & record qualitative observations in your data table. Draw a image of your egg Record the date & time of measurement. Record how many hours the egg was in solution. Use a sharpie to record the egg’s new height. Use a ruler in millimeters to measure the difference and record on the data table. Carefully, pour remaining liquid into the sink without pouring out your egg. (Use the spoon to keep the egg from leaving the cup). Measure the mass of the egg in the cup. Subtract the original mass of the cup to determine the remaining mass of the egg. After Completing data collection, return the egg to the teacher. The class will POP the eggs together to inspect the inside Prepare to make qualitative observations of the opened egg. Calculate the percentage of change to determine what percent of the eggs new size represents how much it changed? (Follow math instructions on data table) Report the percentage of change to the teacher for the class data table