Egg Osmosis Lab Report

Eggmosis

Purpose

The purpose of this lab was to investigate osmosis effects on a real cell.

Hypothesis

If the egg is placed into corn syrup, then it will shrink.

If the egg is placed into distilled water, then it will swell.

Background Information

This lab demonstrates one type of molecular movement, passive transports, displays the effects solutions have on a cell, a chemical reaction, and how the cell membrane works.

Passive transports do not require any energy because the molecules move from an area of high concentration to low. Diffusion, a type of passive transport, is the net movement of the same kind of molecule that pass through the phospholipid bilayer. Osmosis, a type of diffusion, is the diffusion of specifically water through a selectively permeable membrane and as the concentration of water in a solution increases, the concentration of solutes will decrease.

There are three types of solutions that are used in this lab.

Isotonic solutions are when the solute concentration outside of the cell is the same as it is on the inside of the cell. Water moves both in and out of the cell, there is no net water movement, and this solution has no effect on the cell. Hypertonic solutions have a higher solute concentration outside of the cell than inside, will make a cell shrink, and the net movement of water is water moving out of the cell. Hypotonic solutions are the opposite of hypertonic solutions. This solution has a higher solute concentration on the outside of the cell than the inside, the net movement of water is into the cell, and causes cells to swell and possibly

burst.
Vinegar is an acetic acid and when chemically combined with calcium carbonate; it creates carbon dioxide. The cell membrane is a selectively permeable boundary, meaning it controls what enters and exits the cell. The cell membrane is made up of a phospholipid bilayer. This bilayer is composed of hydrophilic heads with two hydrophobic tails, cholesterol, transport proteins, and carbohydrate chains. These water-attracting heads, water-avoiding tails, and transport proteins control how molecules enter and leave the cell. Cholesterol helps to maintain the membrane flexibility and makes the membrane less permeable. Carbohydrate chains allow cells to recognize each other.

Materials

Egg
500 ml beaker
Vinegar
Corn syrup
Distilled water
Digital balance scale
Pencil
Paper

Procedure
Day 1
Obtain an egg.
Use the digital balance scale to measure the egg’s mass.
Record the mass.
Place egg in beaker.
Fill beaker with vinegar enough to cover egg.
Day 2
Record observations.
Gently remove egg from beaker.
Dispose of vinegar in beaker.
Place egg into beaker.
Repeat Step 5.
Repeat Step 6.
Day 3
Hypothesize the effect of caro syrup on the egg.
Hypothesize the effect of distilled water on the egg.
Remove the egg from the beaker.
Rinse out the beaker until vinegar is gone.
Record mass of egg.
Place egg into beaker.
Cover egg with corn syrup until it floats.
Record observations.
Day 4
Remove egg from beaker.
Rinse out beaker.
Record the mass of egg.
Record observations.
Place egg into beaker.
Fill beaker with distilled water until egg is covered.
Day 5
Remove egg from beaker.
Dispose of distilled water.
Wash beaker.
Record mass of egg.
Make observations.
Dispose of egg.
Data & Results
Egg Treatment Weights Equation ~ Final-InitialInitial 100
Treatment
Mass (grams)
% Change
Original Egg
59.21 grams

Vinegar
86.36 grams
45.85%
Caro Syrup
40.11 grams
-53.55%
Distilled Water
96.18 grams
139.79%
Table 1: Mass and percent of change after each treatment.

Conclusion
The purpose of this lab was to investigate the effects of osmosis on a cell. The hypotheses made stating that, “ if the egg is placed into corn syrup, then it will shrink” and, “if the egg is placed into distilled water, then it will swell” were accepted.