The hypothesis of this experiment goes as follows, If we place potato cells in a salt solution, then the cells will shrink. They will shrink because when the salt is added the water in the potato, where there is high concentration, will move to the outside of the potato where there is low concentration.
If we place the potato in a sucrose solution with a similar solute concentration as a potato, then the least amount of water will diffuse into or out of the potato cells. This occurs because this scenario will be initially closest to an isotonic solution, allowing us to determine the solute concentration of a potato. Materials: * Knife/ Cork Borer * Seven 30 cm pieces of Dialysis tubing * Thirteen 250 mL Beakers * 15% Glucose Solution * Glucose Test Strips * 1% Starch Solution * Distilled water * Lugol’s solution * 25 mL of: * .2 M sucrose * .4 M sucrose * .6 M sucrose * .8 M sucrose * 1 M sucrose * Paper Towels * Clock * Potatoes * Plastic
Effect of Surface Area to Volume Ratio on Diffusion Rate of Glucose from Potatoes Abstract: The experiment was conducted to determine if differences in surface area had a significant effect on diffusion rate of glucose from potatoes. Potato samples of three different lengths were collected through a process of coring along the middle of the vegetable. Cores were soaked in distilled water for a period before an o-dianisidine-enzyme solution was added. Glucose diffusion rates were determined by using a spectrometer after a period of incubation of the potato samples. Glucose levels were measured at 0.52, 0.57, and 0.67 showing that an increase in surface area corresponded with a non-significant (p=0.096) increase in the glucose diffusion rate.
If the area around a cell has a higher water concentration it will gain water by osmosis. This is because the water molecules surrounding the potato cell are able to pass freely across the cell membrane in both directions; therefore more water will enter the potato than will leave it so it will swell up. Furthermore, if the area around the potato’s cells has a lower concentration of water than the cell will loose water by osmosis due to more water diffusing out through the partially permeable membrane than entering the cell, this will lead to a reduction in the size of the cell. When the concentration of water molecules in the potato is near equal to that of the area around it, the rate of osmosis will decline and the cell will stay the same size, as there is an equal amount of water entering the cell than there is leaving it. Below is a drawn diagram showing the process of osmosis.
(Damon, )Since the movements of substances in passive transport take place from an area of high concentration to an area of lower concentration until both areas reach equilibrium, the water molecules will move from the potato strips to the sugar solution when there is less water concentration in the solution. Therefore, this means that as the sugar solution concentration increases, there will be more sugar molecules in the solution and less water molecules, therefore lowering the water concentration in the solution, causing the water molecules from the potato strips to move from the higher concentration area to the sugar solution with lower concentration. Vise versa, when there is lower concentration of sugar solution, there will be an increase of water concentration in the solution, therefore water molecules will move from the solution to the potato strips where there will be a relatively lower water concentration. IV) Variables: Independent- concentration of sugar solution (mol per dm³) Dependent- change in length of potato strip (cm) Control- initial length of potato strips (2cm); type of solution (sugar); type of potato b) Controlling Variables I) Independent: - The concentration of the sugar solution would be changed by using different volume of solvent to dilute the solute which would be measured by the
Biotechnology can be used to slow down the process of food spoilage. It can thus result in fruits and vegetables that have a greater shelf life. Genetic Modification to Produce New Foods Genetic engineering in food can be used to produce totally new substances such as proteins and other food
Reticulum: in here, food and cellulose is digested by microbes ------ microbes are bacteria/ single celled eukaryotes ------ cows don't have enzymes to break down cellulose, so microbes do it for them ------ huge amounts of saliva create a good environment to help microbes digest the food ------ the food then goes back up to the esophagus to be chewed again and to make nutrients available for both cows and microbes --3. Omasum: water re absorption ------ Regurgitated food comes back as "cud" into reticulum and then to the Omasum --4. Abomasums: acidic environment where whatever is remaining is digested. excess microorganisms are harvested and digested. - NUTRIENTS (that they get): -- Sugars and proteins from grass are directly absorbed -- absorbing microbial digested grass molecules (cellulose --> glucose) --actual microorganisms themselves (they leak out sugars, fatty acids, etc.
Cody Baycroft Mrs. Vance AP Biology pd.3/6 7 October 2011 Effect of Solute Concentration on Water Potential Research Question: Investigate the concept of water potential in relation to the movement of water into or out of a plant cell (potato). This will be researched by immersing potato cores in sucrose solutions (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1.0M) and determining the change in mass (in percent) of the cores. Hypothesis: If the solute concentration is increased, then the water potential of solution will have increasingly more negative values. In other words as the concentration of the sucrose solutions becomes more hypertonic than the potato core (the solution has greater solute concentration and lower water potential) the potato will begin to loose mass since water will leave the hypotonic potato core (the core has less solute concentration hence higher water potential) to the hypertonic solution in order to dissolve the sucrose solution. Water potential is the concept used to combine the differences in solute concentration and pressure to predict the direction in which water will diffuse through the living plant tissue and states that the net movement of water will always be from an area of higher water potential to and area of lower water potential.
Cheese Lab Conclusion The purpose of the cheese lab was to determine which curdling agent curdled the fastest to make cheese and which curdling agent produces the most cheese. There were four curdling agents that we have tested. My hypothesis was that chymosin is expected to produce the most volume of cheese in the shortest amount of time because the particles will bond together creating a solid, making curd the fastest, it will create the most fungus. There was buttermilk, rennin, chymosin, and water. To start off with buttermilk, the time it took to curdle was 30 minutes with 1.5ml of curds.
Osmotic pressure is colligative properties (which are properties of solutions that depend upon the ratio of the number of solute particles to the number of solvent molecules in a solution (Chemistry). Osmosis is essential in biological systems. The aim for this lab report is to assess the effect of weight and length of 5 different concentrations of a salt solution on 6 different potato wedges over 24 hours. To do this we will research how the effect of different salt solution concentrations will have an affect on 6cm length potato wedges. Research Question: How will the different potato wedges submerged in various salt solutions affect on the weight and length of the potato wedges?