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tonicity on cell membrane lab report Essay

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Effects of Tonicity on Cell Membrane

Abstract The purpose of this experiment was to determine the effects of tonicity on a cell membrane using red blood cells, potato strips and three unknown solutions (A, B, C). First three slides were prepared containing RBC’s and unknown solutions A, B and C. A control slide was prepared only using RBC’s. After observing each slide under the microscope it was determined that unknown solution A was hypertonic because the RBC appeared to have shrunk. The RBC in unknown solution B appeared to be swollen, therefor, the tonicity of unknown solution B was hypotonic. Unknown solution C showed no change to the RBC shape, it was suggested that unknown solution C was isotonic. To confirm the tonicity …show more content…

Cells placed in a hypertonic solution will shrink as the solvent leaves the cells.
Plant cells react differently to osmosis than animal cells. When an animal cell is placed in a hypertonic solution, water will leave the cell causing it to shrink, this is known as crenation. When a plant cell is placed in a hypertonic solution the cell membrane will pull away from the cell wall, making the plant flaccid, this is known as plasmolysis. When an animal cell is placed in a hypotonic solution, water will rush in to the cell, causing it to swell and sometimes burst. A plant cell placed in a hypotonic solution will also swell due to water rushing in, but will resist rupturing due to the rigid cell wall. Plant cells become more rigid in a hypotonic solution.
In this activity we will be observing the effects of potato slices and red blood cells being placed in varying molar levels of NaCl.

Methods
The materials used for the first part of the experiment comprised of the following: a microscope, 4 slides, 4 slide covers, blood samples, lancet, a sheet of paper towel, 3 test tube droppers, Solutions A, Solutions B, and Solution C.
Blood samples from a volunteer within the group were used to conduct the experiment. The volunteer’s hands were thoroughly washed and an alcohol swab was applied to further sanitize the hands. To gather the blood samples needed, a lancet was properly placed on the forefinger and a firm pressure was applied, which activated the needle inside to

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