Osmolarity: Concentration and Sucrose Solutions
Estimating Osmolarity by Change in Weight
By: Sondus Kahil
27 February 2012
TA- Ashley Hintz
Biology 200A-section 002
Abstract:
My group and I conducted the experiment that estimates osmolarity by change in weight of potato tubers, this was conducted in order to explore the process of diffusion and osmosis and more importantly to investigate the question of “Does different concentrations of sucrose solutions have an effect on the final weight for the potato tubers?” In this experiment we estimated the osmolarity of potato tuber cores by submersing different potato cores into sucrose solutions of 0.0-0.6M, and weighing the potato. The results showed the weight of the potato tubers had the highest percent change in weight meaning that they weighed more than the initial weight in sucrose solutions from 0.0-0.3M; it also showed that sucrose concentrations from 0.4-0.6M the weight of the potato tubers decreased. My group and I concluded that the osmolarity of the potato was about 0.4M since the weight of the potato decreased by about -1.3%, which was the closest value to the initial weight of the potato tuber. We also found that the potato was hypertonic to sucrose solutions of 0.0-0.3M and hypotonic to 0.5-0.6M.
Introduction:
Diffusion and osmosis are two types of passive transport. Diffusion is a random movement of molecules from an area of high concentration to an area of low concentration. According to the book Biological Sciences, “Osmosis is a type of diffusion that occurs when solutions are separated by a membrane that is permeably to some molecules but not to others, that is, a selectively permeable membrane” (Scott 2011). To further explore the process of diffusion and osmosis, we conducted an experiment that would demonstrate these processes and also investigate the question of “do different concentrations of sucrose solutions have an effect on the final weight for the potato tubers?” In my group’s experiment
By: Sondus Kahil
27 February 2012
TA- Ashley Hintz
Biology 200A-section 002
Abstract:
My group and I conducted the experiment that estimates osmolarity by change in weight of potato tubers, this was conducted in order to explore the process of diffusion and osmosis and more importantly to investigate the question of “Does different concentrations of sucrose solutions have an effect on the final weight for the potato tubers?” In this experiment we estimated the osmolarity of potato tuber cores by submersing different potato cores into sucrose solutions of 0.0-0.6M, and weighing the potato. The results showed the weight of the potato tubers had the highest percent change in weight meaning that they weighed more than the initial weight in sucrose solutions from 0.0-0.3M; it also showed that sucrose concentrations from 0.4-0.6M the weight of the potato tubers decreased. My group and I concluded that the osmolarity of the potato was about 0.4M since the weight of the potato decreased by about -1.3%, which was the closest value to the initial weight of the potato tuber. We also found that the potato was hypertonic to sucrose solutions of 0.0-0.3M and hypotonic to 0.5-0.6M.
Introduction:
Diffusion and osmosis are two types of passive transport. Diffusion is a random movement of molecules from an area of high concentration to an area of low concentration. According to the book Biological Sciences, “Osmosis is a type of diffusion that occurs when solutions are separated by a membrane that is permeably to some molecules but not to others, that is, a selectively permeable membrane” (Scott 2011). To further explore the process of diffusion and osmosis, we conducted an experiment that would demonstrate these processes and also investigate the question of “do different concentrations of sucrose solutions have an effect on the final weight for the potato tubers?” In my group’s experiment
Cited: Freeman, Scott. "Lipids, Membranes, and the First Cells." Biological Sciences. 4th ed. Vol. 1. Boston: McGraw Hill, 2011. 90-91. Print. Karp, Gerald. Cell and Molecular Biology: Concepts and Experiments. New York: J. Wiley, 1999. Print Marvel, Stephen C., and Megan V. Kepler. "A Simple Membrane Osmometer System & Experiments That Quantitatively Measure Osmotic Pressure." The American Biology Teacher 6.7 (2009): 355-62. Print. Mccandless, John. "BIOLOGY.ARIZONA.EDU." BIOLOGY.ARIZONA.EDU. University of Arizona, 27 Feb. 1997. Web. 26 Feb. 2012. .