Name: Abigail Snyder Exercise 1: Cell Transport Mechanisms and Permeability: Activity 1: Simulating Dialysis (Simple Diffusion) Lab Report Pre-lab Quiz Results You scored 50% by answering 2 out of 4 questions correctly. 1. The driving force for diffusion is Your answer : c. the membrane transport protein. Correct answer: b. the kinetic energy of the molecules in motion. 2. In diffusion, molecules move You correctly answered: a. from high concentration to low concentration. 3. Which of the following dialysis membranes has the largest pore size? You correctly answered: d. 200 MWCO 4. Avogadro's number is a constant for the number of Your answer : a. moles. Correct answer: b. molecules.

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Experiment Results Predict Question: Predict Question 1: The molecular weight of urea is 60.07. Do you think urea will diffuse through the 20 MWCO membrane? Your answer : c. No, not at all. Predict Question 2: Recall that glucose is a monosaccharide, albumin is a protein with 607 amino acids, and the average molecular weight of a single amino acid is 135 g/mole. Which of the following will be able to diffuse through the 200 MWCO membrane? Your answer : c. glucose only Stop & Think Questions: The reason sodium chloride didn't diffuse left to right is that You correctly answered: c. the membrane pore size was too small. Glucose is a six-carbon sugar. Albumin is a protein with 607 amino acids. The average molecular weight of a single amino acid is 135 g/mole. There is no reason to run these solutes at the 20 MWCO because You correctly answered: d. glucose and albumin are both too large to pass. The rate of diffusion for urea You correctly answered: b. is slower than that for sodium because urea is a larger molecule. Experiment Data: Solute Na+ ClUrea Albumin Glucose Na+ ClUrea Albumin Glucose Na+ ClUrea Albumin Glucose Na+ ClUrea Albumin Glucose Na+ ClUrea Albumin Glucose Na+ ClUrea MWCO 20 20 20 20 20 20 20 20 50 50 50 50 50 50 50 50 100 100 100 100 100 100 Left Solute Concentration 9.00 0.00 0.00 0.00 0.00 9.00 0.00 0.00 9.00 0.00 0.00 0.00 18.00 0.00 0.00 0.00 9.00 0.00 0.00 0.00 0.00 9.00 Right Solute Concentration 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Average Diffusion Rate 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0150 0.0000 0.0000 0.0000 0.0273 0.0000 0.0000 0.0000 0.0150 0.0000 0.0000 0.0000 0.0000 0.0094

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Solute Albumin Glucose Na+ ClUrea Albumin Glucose Na+ ClUrea Albumin Glucose

MWCO 100 100 200 200 200 200 200 200 200 200

Left Solute Concentration 0.00 0.00 0.00 0.00 0.00 9.00 0.00 0.00 9.00 0.00

Right Solute Concentration 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Average Diffusion Rate 0.0000 0.0000 0.0000 0.0000 0.0000 0.0042 0.0000 0.0000 0.0000 0.0000

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Post-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1. The effect of increasing the concentration of sodium chloride from 9 mM to 18 mM in the left beaker was to You correctly answered: b. increase the rate of diffusion. 2. Describe the difference