Post on 31-Mar-2015
transcript
EGG-SPERIMENTWe are starting a new experiment today!
• When we look at eggs placed in vinegar…• The vinegar produced gas bubbles
dissolved egg shell• All that we’re left with is a membrane!
EGG-SPERIMENT Prelab1. What does the cell membrane do?Controls what moves in and out of the cell2. What are 2 vocabulary words you should
associate with the cell membrane?Selectively permeable Homeostasis
EGG-SPERIMENT
This experiment will let you see how
the cell membrane can be selectively
permeable to different solutions (corn
syrup, water) to maintain homeostasis!
EGG-SPERIMENT
Scientific Question:
How does the weight of the egg
change when it is placed in different
solutions (corn syrup, distilled water)?
HYPOTHESIS: (IF… THEN…)1. If the egg is placed in water then….
2. If the egg is placed in corn syrup then…Hypothesis: Three things could happen when the egg is in corn syrup or distilled water:- Weight increases - Weight decreases- Weight stays the same What do you think is going to happen?Weight decrease in corn syrupWeight of the egg will increase in distilled waterWeight will stay the same in both corn syrup or waterWeight of the egg will increase in distilled water
EGG-SPERIMENT DO NOT WRITE YET!!
Listen to what you’ll be doing…
Variables and Procedures
1) Today we are going to take the INITIAL weight of the egg BEFORE we put it in any type of solution
EGG-SPERIMENT
Variables and Procedures
2) Today we are going to put our eggs in different solutions:
- corn syrup - distilled water
EGG-SPERIMENT DO NOT WRITE YET!!
Listen to what you’ll be doing…
EGG-SPERIMENT
Variables and Procedures3) Tomorrow we are going to take the
eggs out. We’re going to take the FINAL weight in corn syrup and distilled water.
EGG-SPERIMENT DO NOT WRITE YET!!
Listen to what you’ll be doing…
EGG-SPERIMENT
Variables and Procedures
3) Tomorrow we are going to write a lab report about what we did and look at our results.
EGG-SPERIMENT DO NOT WRITE YET!!
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Cells in ActionEGG-SPERIMENT
• Pay attention as we go over the details of what we are going to be doing!
EGG-SPERIMENT DO NOT WRITE YET!!
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EGG-SPERIMENT
SAFETY!!
Wear gloves
No horse play.
Please handle your eggs VERY GENTLY!
REMINDER… Headphones/electronics in lab = 0 on your lab report. You will have to make up that grade in coach class.
EGG-SPERIMENT DO NOT WRITE YET!!
Listen to what you’ll be doing…
EGG-SPERIMENT
PROCEDURES
Summarize what was just explained to you.
SAFETY!!
How will you be safe in the lab?
NOW YOU MAY WRITE OUT YOUR PROCEDURES
1st Period DATAMass of Egg (Corn Syrup) Mass of Egg (Distilled Water) Mass of Egg #3 (Air)
CONTROL!!!!!
Group Members Names
INTIAL FINAL INITIAL FINAL INITIAL FINAL
1 *Mrs. Doney will do this.Write the mass she tells you here:
*Mrs. Doney will do this. Write the mass she tells you here:
2
3
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5
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8
2nd Period DATAMass of Egg (Corn Syrup) Mass of Egg (Distilled Water) Mass of Egg #3 (Air)
CONTROL!!!!!
Group Members Names
INTIAL FINAL INITIAL FINAL INITIAL FINAL
1 *Mrs. Doney will do this.Write the mass she tells you here:
*Mrs. Doney will do this. Write the mass she tells you here:
2
3
4
5
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8
WHAT’S GOING ON?To understand what’s going on in the egg-
speriment, we have to learn about 3 types of solutions and remember what we learned about diffusion
EXIT SLIPIn this picture, the small black dots are the SOLUTE. The SOLVENT is water. Assume that the cell membrane is selectively permeable to WATER ONLY!
QUESTIONS: 1) Is there a greater amount of solute inside the cell or outside the cell?2) Is there a greater amount of solvent inside the cell or outside the cell?
3) Will water move into the cell or out of the cell?4) Will the cell shrink in mass, increase in mass, or have no change in mass?5) BONUS Is this cell in a hypertonic, hypotonic, or isotonic type of solution?