ES
Diffusion Across a Selectively Permeable Membrane
Abstract
· A summary of the lab report. This includes a short summary for each section.
Introduction
· Background (answer the following questions):
· What factors determine whether substances can diffuse across a selectively permeable membrane? What factors influence the speed of diffusion?
· According to the laws of diffusion, which molecules are more likely to diffuse? Glucose or Starch?
· Objective (what questions are we trying to answer)
· Hypothesis
Methods
· What methods were used?
· What materials did you use to indicate the presence of glucose? Starch?
Results
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Table 1: Diffusion of Starch and Glucose over Time Was substance present? |
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Dialysis Tubing Prior to closing (Positive Control) |
Beaker Before Diffusion (Negative Control) |
Dialysis Tubing After Diffusion |
Beaker After Diffusion |
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Iodine |
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Starch |
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Glucose |
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If glucose present, how much? (mg/dL) |
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Discussion
· Of the two substances tested, which, if any, crossed the dialysis membrane? Did either of the substances stay in the bag? Support your response with data-based evidence (I.e. what did the indicators tell you). Did our diffusion experiment results reflect the laws of diffusion? Explain by comparing our data to the molecular weights of each molecule.
· Was your hypotheses correct? Why or why not?
· Using physiological reasoning, explain the outcome of the experiment? What influenced whether the substance diffused across the membrane? (HINT: Look up the molecular weights for both substances).
References
· List any references you used in proper APA format.