Part A: Osmosis practical task Aim: To observe the effects of osmosis in rhubarb cells. Hypothesis: Water will be extracted out of the cells in the salt solution causing the cells to look different to the cells in the freshwater solution. Materials: Rhubarb Distilled water in a dropping bottle Salt solution in a dropping bottle Microscope, slides, and coverslips Forceps and razor blades or scalpel Paper Towel Method: Clean and dry a slide and coverslip. Obtain a small sample of the red epidermal cells from the stalk of the rhubarb by carefully peeling away the layer with forceps. Prepare a wet mount slide of the rhubarb tissue in distilled water only. View your slide under low power on your microscope, and then switch to high power. Draw a diagram of the field of view, and label. Irrigate your slide with the salt solution. Leave for a few minutes. View one of your slides under low power on …show more content…
Additionally, it was difficult obtaining a piece of rhubarb that was thin and particularly red, therefore the effect could not be best observed in the cells. Part B: Design your own experiment Parts of this practical were taken and slightly altered from the following link http://www.markedbyteachers.com/gcse/science/investigate-the-effect-of-surface-area-on-osmosis-in-potato-tissue.html Aim: To observe the effect different surface area: volume ratios have on osmosis in potato tissue. Hypothesis: If the potato has a larger surface area: volume ratio, the quicker osmosis will take place and the larger the mass will be at the end of the experiment, therefore the difference in mass of the potatoes from the start of the experiment to the end of the experiment will be larger. Additionally, the potato pieces left in a saltwater solution will decrease in mass, whereas the pieces left in water will increase in mass. Materials and Equipment 2 Large potatoes Vegetable peeler Knife Chopping
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We then obsevered the two slides for number of cells as well as for food vacuoles inside a cell using a microscope at times of 0,5,10,20, and 30 minutes. Results The following graphs show the results of this experiment. The tetrahymena sample that was introduced to concentrated tobacco had a lower cell/vacuole ratio than the tetrahymena sample that was not exposed to
LABORATORY REPORT EXERCISE #5 INTRODUCTION TO THE COMPOUND LIGHT MICROSCOPE, PLANT AND ANIMAL CELLS Name_______________________________Section_____Teacher______________Date________ PRE-LAB QUESTIONS - answer the following questions using your textbook and valid internet sources. Be sure to cite your sources at the end of the prelab. You can type your answers to all questions except #1 and #9 directly into this document and then submit via Canvas. Type the answers for #1 and #9 at the end of the document. 1.
This was calculated using the C1V1=C2V2 formula. A photo spectrometer was used to measure, in arbitrary units, the change in membrane permeability of the B. Vulgaris cells. To begin, the B. Vulgaris samples were put into vials containing the distilled water, 40% and 70% Ethanol
This also shows how much water was transferred from the egg to the sugar solution. The higher the percentage of corn syrup was, the faster the rate of osmosis was. As a result, the egg placed in 75% corn syrup, 25% filtered water had the lightest weight (0.5 oz), while the egg placed in 25% corn syrup, 75% filtered water weighed 2 oz. Overall, the importance of this lab was to understand the process of osmosis and how it differs depending on the type of
Diffusion and Osmosis Lab Report By: Jettica Williams BIOL 1107 Lab September 21, 2016 Prepared for Mrs. Fulford Lab Course Page Break The cell membrane act as a roadblock for cells. The cell membrane has a very hectic job. It restricts the access to what comes in and what goes out. The bond the membrane shares with others is the idea of accountability.
First, it was hypothesized that test tube "A", the control, would not show any red concentration, test tube "B" which contains supernatant II would show the most red concentration and test tube "C" which contains sediment II would only show a little red concentration. The second hypothesis states that the raw corn kernels would have mitochondrial activity while the boiled corn kernels would not. The last hypothesis interprets that the "gunk" and sediment I will both contain starch granules. It was only expected to find mitochondrial activity in Supernatant II. Unfortunately, after performing this experiment, we were not able to support this hypothesis and come up with a conclusion.
Because carbon dioxide is absorbed by the plant during photosynthesis less carbon dioxide present in the chamber is a sign that photosynthesis is working. The four lights used for this experiment range across the light spectrum on both sides in order to test a wider variety of wavelengths. All lights will be placed directly on the spinach leaf at the same distance so as not to give any spinach leaf a different light intensity, which could affect the data. This experiment will be able to show which light, ranging across the light spectrum, will allow the Spinach to perform photosynthesis more efficiently.
The overall project goals and central questions that has to do with the project is mostly trying to determine the isotonic concentration of the salt in potato roots and the use of the ideal soil salt conditions for the potato plant growth. In part 2, we had to test the enzyme activity that is in the was involved in the potato, so we can also determine the ideal soil pH conditions for the potato plant growth. In part 3, we were able to test absorb the leaf pigment at various wavelengths that determine the optimum light absorption conditions and was able to make recommendations for the light conditions that would be used un greenhouses. The goal of the first project is to determine the ideal soil salt for potato roots and we can relate this to the project is to find out if Solution A or Solution B has more solute in it. The goal of this project is to determine the meaning of Osmosis.
Background Information: In this experiment I will be investigating the impact of light intensity on the rate of water uptake, due to transpiration, by attaching a shoot from a leafy plant in the capillary tube of a potometer, and then measuring how long it takes for a bubble to move a set distance. The faster the bubble moves, the greater the rate of transpiration. I will be placing one plant in an environment where it is exposed to high-light intensities, and another plant in an environment where it is exposed to low-light intensities. Transpiration is the process of the transport of water and nutrients up the the plant from the roots to the leaves.
For this lab I will be using water and sucrose to demonstrate the rate of osmosis. In this lab I will be exploring how temperature impacts the rate of osmosis by placing pieces of potato of equal size in solutions of different temperatures and observing the change in mass of potato after a given period of time. The change in mass will indicate the rate of osmosis.
Biology Design Practical Joshua Edwards What are effects of the volume of a potato and the amount of weight it loses when placed in salt solution? Introduction This design practical uses a potato’s surface area to volume ratio to see what affects it has on osmosis in different concentrations. Osmosis is the movement of water molecules through a cell membrane into an area of a higher solute concentration. The movement goes the way of the solvent with more solute because the lower solute concentration is drifting through balancing the ratio of solute per solvent (En.wikipedia.org, 2018).
By using the same mass of potato slices and putting them in different concentration of solutions for a specific amount of time will tell us how the concentration changes the mass of the potato slice. Therefore changing the rate of osmosis. Hypothesis: I predict that, if the piece of potato was put into a solution that has a high concretion of sucrose then the potato slice would lose mass as it would lose water from its cells because the water is moving out of the cell from a high concentration to a low concentration of water through a semi- permeable membrane. The cell is hypotonic and the solution is hypertonic.
Methanol, has a molecule containing CH3OH it being the smallest, ethanol having more carbons and hydrogens than Methanol comes second, CH3CH2OH, and propanol, CH3CH2CH2OH, is the largest of the three molecules. Aim: The aim of this experiment is to see the effects of different alcohols and concentrations on the biological membrane of the beetroot. Research Question: How do different alcohols and concentrations affect the biological membrane of a beetroot? Hypothesis: As the alcohols increase in toxicity and concentration, the damaging and breaking down of the membrane will increase leading to more red pigment being released into the solution causing the absorption of the solute to increase.
In this experiment, beets will be a replica to explore membrane using various extremely low and high temperatures. The roots of beet contain an immense quantity of a reddish color called betacyanin that is located inside the central vacuoles, which are surrounded by a vacuolar membrane called the tonoplast (Biology Lab Manual, 2011). The protein structure of beetroot is very important, because once its interrupted it could lose its purpose and would have to experience denaturation. Cell membranes defend and organize cells, they serve as a fence which means that a few particles can disperse across the lipid bilayer but others cannot. The structure of the cell membrane contains