Title: Alexandra Whitaker, Ms.Dayton, 12/23/16, 2.03 lab permeability Objective(s): The main purpose is to find out if plastic bags are permeable to starch and, or, iodine. Also, to find out wither potatoes are hypotonic, hypertonic, or isotonic by testing the different amounts of sucrose solutions Introduction: The necessary background information needed for this lab is the definition of osmosis, diffusion, active transports, passive transports, permeability, concentration, tonicity, and to now the scientific concepts of hypotonic, isotonic, and hypertonic. Hypothesis: For part 1 my hypothesis is: That the starch will diffuse across the plastic bag and react with the iodine and will have a color change to the water to imply the reaction…
Tetrahymena contractions with different solutions Purpose: How fast will the Tetrahymena contractile vacuole contract in different solutions? Introduction: In this experiment, the organism that is used are the Tetrahymena.…
State the optimum pH for sucrase activity and describe how sucrase activity changes at more acidic and more alkaline pH values. Table 2: Effect of Temperature on Sucrase Activity Optical Density 10 °CC (50 °F) 20 °C (68 °F) 30 °C (86 °F) 40 °C (104 °F) 50 °C (122 °F) 60 °C (140 °F) 70 °C (158 °F) 1 0.006 0.273 0.791 0.940 0.927 0.807 0.613 2 0.010 0.285 0.761 0.954 0.934 0.846 0.604 3 0.009 0.255 0.773 0.941 0.907 0.845 0.642 average 0.008 0.271 0.775 0.945 0.923 0.833 0.620 Effect of Temperature on Sucrase Activity 2. Was the rate of increase of sucrase activity higher at a pH of 8.5 or a pH of 5.5?…
Discussions Bag A stimulates cell whose contents are hypotonic to its environment. The situation is because the concentration of the dissolved substances in the cell is less than the surrounding media. In this case, the cell contents contain 1% sucrose solution that is less concentrated than the 50% surrounding media. Therefore, a large concentration gradient develops between the two media. Consequently, because of the high concentration gradient, the bag loses water faster and this leads to its reduction in volume.…
It requires energy. 5. Cells would use too much energy just for transporting molecules. This might cause the organism/animal to spend most of its time taking in energy by eating. Cells would require vast amounts of energy to perform even simple functions.…
This process showed how each solution affected the egg’s rate and direction. Osmosis is the diffusion of water across a differentially permeable membrane. Moving across a semi-permeable membrane, the water diffuses from a range of high concentration to a range of low concentration. This is made possible by the presence of a concentration gradient. For this experiment, the eggs were examined due to the shifting of the solution across the membrane.…
This lab provided a good perspective of the movement of molecules diffusing and going through osmosis into a cell. The ability of the cell membrane to be selective was illustrated by it not allowing all the molecules through (starch). This shows how in a real cell it can differ between essential and nonessential or invading molecules. Lastly, It gave a good example of hypertonic solutions and how the concentration gradient…
Osmosis is the net movement of water towards higher concentration. In osmosis experiment, water likes to diffuse from an area of low-solute concentration to an area of high-solute concentration. The purpose of the osmosis experiment was to observe the diffusion of solutes and the osmosis of water through a semipermeable membrane, which was dialysis tubing. This experiment was done to examine, if the solution is hypertonic, hypotonic or isotonic.…
Observing the Effects of Osmosis on Model Cells of Different Sucrose Concentrations Cells are the building block of life. But these cells aren’t a closed system. There is a constant movement of various molecules in and out of the cell that brings nutrients in and brings waste out. This movement of particles in and out of cells is based around osmosis.…
Method: In this experiment each group received 2 chicken eggs whose shells have been dissolved off. This gave us a differentially permeable membrane so that we can observe osmosis and what happens when the membrane is presented with different solutions. Since we did not know the concentration of the egg, we had to assume that it equaled the concentration of the membrane. We then had the ability to determine the concentration based off the assumption and the rate of osmosis.…
Observing Osmosis INTRODUCTION Osmosis is the “diffusion of water across a selectively permeable membrane” (Raven et al. G-16). In this experiment, dialysis tubing was used to mimic the selectively permeable membrane to show what osmosis does when placed in different solutes. We filled dialysis tubes fill with different percentages of solute and placed them in beakers full of a different solute. Through this experiment, I saw what happens when the solution becomes hypertonic, hypotonic, and isotonic. My hypothesis was that bag A would shrink because the water would leave the bag to go to the higher concentration.…
The purpose of this EEI is to create and analyse an experiment that relates to and supports the theory of osmosis in biological cells. Cells are the biological building block for all life; all living organisms have cells also. Cells provide structure, absorb nutrients from food and convert those nutrients into energy so that the cell can carry out specialized functions. There are two main categories with most organisms and their cells; prokaryotes and eukaryotes. The distinctive difference between prokaryotes and eukaryotes is that eukaryotic cells contain membrane-bound organelles, such as the nucleus, while as prokaryotic cells do not.…
We were interested in this experiment because we were recently studying the layers of the earth and we thought it would be interesting to learn soil porosity. Porosity or pore space is the amount of air spaces between soil particles. During our experiment we found out that the more volume of water there was the faster it moved. The more volume of water that can go through the soil the faster it moves, resulting in more porous soil!…
After the experiment, the concentrations of the unknown solution was found through reviewing the mass change and water potential found. The lowest…
PURPOSE/QUESTION The question that we will answer using this laboratory report is, “How is the rate of dissolving sugar affected by changing the temperature of the water, changing the rate of stirring, and changing the size of the crystal?” The independent variable of each laboratory experiment is different, however they are all being changed to get consistent and effective results for one dependent variable. The three independent variables are the temperature of water, rate of stirring and size of the crystal and the dependent variable of the all the experiments is the rate of sugar dissolving. HYPOTHESES Below are the laboratory experiment hypotheses that we have formed as a group to figure out what will happen to the rate of dissolving under…