Regents Biology 3BCD
Osmosis and Plasmolysis
Problem: What is the effect of Osmosis on a chicken egg? What is the effect of different solutions with various concentrations on plant cells?
Hypothesis: 1. In an animal cell in a hypertonic solution the egg will swell, in a hypotonic solution the egg will swell. 2. In a plant cell in a hypertonic solution it will shrink, and in a hypotonic solution it will swell.
Methodology: Part 1. A chicken egg is consecutively over time placed in each of 3 jars, each containing vinegar, syrup and water. The eggs appearance was observed and recorded. Part 11. An elodea leaf cell is observed with salt solution, and without salt water but with distilled water. Observations on appearance and changes were recorded.
Results: Part 1. The Mass of the egg increased and the volume of the egg decreased in both Vinegar and Water solutions. The mass of the egg decreased and the volume increased in the syrup solution. Part 11. The elodea leaf cell gets larger when distilled water was added compared to when salt solution was added to the cell.
Discussion: Part 1. In part 1 of this lab it was proved that in a hypertonic solution animal cells shrink and that in a hypotonic solution an animal cell swells. The water molecules moved into the egg when the egg was placed in vinegar. If the eggs mass increased, the volume of the egg decreased. The liquid from the egg moved out into the beaker when the egg was removed from the syrup. When the egg was placed in water after the syrup, the water moved into the egg. Part 11. In part 2 of this lab it was proved that in a hypertonic solution plant cells shrink and in a hypotonic solution plant cells swell. When salt solution was added to the cell the cell shrinks and when the distilled water was added to the cell, the cell shrinks stating the results.
Errors in this lab included not having