Osmosis Lab Report
Osmosis
The purpose of this lab is to study how membranes of plant and animal cells react when exposed to different solutions. The first experiment involves purple onion skin and the second involves rat blood in various solutions.
I needed to understand certain terms before preforming this lab to be able to efficiently explain what is happening to the cells. Diffusion is the tendency of a substance to move down its concentration gradient from a more concentrated to a less concentrated area. Facilitated diffusion is the spontaneous passage of molecules and ions bound to a specific carrier protein across a biological membrane down their concentration gradient. Active transport is the movement of a substance across a biological membrane …show more content…
I then added two drops of rat blood to the first test tube and started the timer. I swirled the solution and placed an index card behind the test tube to see if I could observe the lines of the index card through the solution. If after two minutes I couldn’t see the lines, I moved on to the next test tube and added two drops of rat blood. The same protocol followed with the remaining solutions; if after two minutes the lines from the index card are not visible, move on to the next solution. I recorded the time it took to see the lines of the index card on the chart provided in the lab. If after 30 minutes and the lines of the index card were not visible, the records should state “no hemolysis”.
In the first experiment, I observed the onion membranes under a microscope when it was placed in different solutions. The first onion membrane I observed was placed in water. The cells looked swollen and tightly compacted. When I observed the onion skin in 0.3M sucrose, the cells were loosely compacted. I last observed the onion membrane in 2.0M sucrose and the cells looked very thin and far apart from each other in comparison to the other slides. Table 1 shows the data I
The purpose of this lab is to study how membranes of plant and animal cells react when exposed to different solutions. The first experiment involves purple onion skin and the second involves rat blood in various solutions.
I needed to understand certain terms before preforming this lab to be able to efficiently explain what is happening to the cells. Diffusion is the tendency of a substance to move down its concentration gradient from a more concentrated to a less concentrated area. Facilitated diffusion is the spontaneous passage of molecules and ions bound to a specific carrier protein across a biological membrane down their concentration gradient. Active transport is the movement of a substance across a biological membrane …show more content…
I then added two drops of rat blood to the first test tube and started the timer. I swirled the solution and placed an index card behind the test tube to see if I could observe the lines of the index card through the solution. If after two minutes I couldn’t see the lines, I moved on to the next test tube and added two drops of rat blood. The same protocol followed with the remaining solutions; if after two minutes the lines from the index card are not visible, move on to the next solution. I recorded the time it took to see the lines of the index card on the chart provided in the lab. If after 30 minutes and the lines of the index card were not visible, the records should state “no hemolysis”.
In the first experiment, I observed the onion membranes under a microscope when it was placed in different solutions. The first onion membrane I observed was placed in water. The cells looked swollen and tightly compacted. When I observed the onion skin in 0.3M sucrose, the cells were loosely compacted. I last observed the onion membrane in 2.0M sucrose and the cells looked very thin and far apart from each other in comparison to the other slides. Table 1 shows the data I