Lab Report on Osmosis

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 Introduction
A computerized simulation experiment will be conducted in order to study the cell transport mechanism via the cell’s selectively permeable membrane and passive processes of simple and facilitated diffusion. The plasma membrane is a gateway which allows nutrients to enter the cell and keep undesirable substances out, hence, making it selectively permeable. One method of transport is called active transport, which uses ATP to transport substances through the membrane. The other is called passive process, which does not require ATP energy and the transport process is driven by concentration or pressure differences between the interior and exterior of the cell. All molecules are in constant motion, ergo, possessing kinetic energy. This kinetic energy is the motivating force in diffusion. During diffusion, molecules that are small enough to pass through a membrane’s pores or molecules that can dissolve in the lipid bilayer of a membrane move from an area of higher concentration to an area of lower concentration. Facilitated diffusion occurs when molecules are too large to pass through a membrane or are lipid insoluble. Thus, in the process, carrier protein molecules located in the membrane combine with solutes and transport them down the concentration gradient.

Hypothesis
Activity One: Simple Diffusion- Simulating Dialysis
Simple diffusion will occur between different concentrations until equilibrium is reached. Activity Two: Simulating Facilitated Diffusion
Facilitated diffusion will occur between different concentrations. Material and Methods
* Two beakers
* Membrane holder
* Four Dialysis membranes: 20 (MWCO), 50 (MWCO), 100 (MWCO), 200 (MWCO). * Membrane barrier
* Four solutes: NaCl, Urea, Albumin, Glucose
* Solution dispenser
* Deionized Water
* Beaker Flush
* Timer
* Computerized Simulator
Using the computerized simulator, the first step of the first experiment, you must place the 20 (MWCO) dialysis membrane into the membrane holder. The membrane holder is joined between two glass beakers; one on the left, the other to the right. Next, 9.00 (mM) of NaCl concentration is dispensed into the left beaker and deionized water is dispensed in the right beaker. As the timer begins, the barrier that surrounds the membrane holder lowers to allow the contents of each beaker to come into contact with the membrane. After 60 minutes of compressed time elapsed, results were shown and recorded. Final step requires the beakers to be flushed for preparation of the next experiments. The exact steps were followed using each dialysis membrane size 20 (MWCO), 50 (MWCO), 100 (MWCO) and 200 (MWCO); as well as with each solute; NaCl, Urea, Albumin, and Glucose. There were a total of sixteen runs in the experiment. Activity Two: Simulating Facilitated Diffusion

Material and Methods:
* Two glass beakers
* Membrane builders
* Membrane holders
* Solution dispenser
* Timer
* Glucose concentration
* Beaker Flush
* Deionized water
* Computerized Simulator
Using the computerized simulator for this experiment, the first step is to adjust the glucose carrier to 500 so to correctly build the membrane. Next, the membrane is built in the membrane builder by inserting 500 glucose carrier proteins. Then, the newly built membrane is placed into the membrane holder that joins between the two beakers. 2.00 (mM) of glucose concentration is dispensed into the left beaker and deionized water is filled in the right beaker. After 60 minutes of compressed time, results were shown and recorded. Final step requires the beakers to be flushed for preparation of the next experiments. The exact steps were followed and repeated by increasing the glucose concentration to 8.00. Both the 2.00 (mM) and 8.00 (mM) glucose concentration solution were tested using membranes with 500,700, and 900 glucose carrier proteins. There were a total of six experimental runs....
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