Exercise 1: Cell Transport Mechanisms and Permeability: Activity 1: Simulating Dialysis (Simple Diffusion) Lab Report
Pre-lab Quiz Results
You scored 100% by answering 4 out of 4 questions correctly.
1. The driving force for diffusion is
You correctly answered: 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
You correctly answered: b. molecules.
06/17/14
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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
MWCO
Left Solute Concentration
Right Solute Concentration
Na+ ClUrea
Albumin
Glucose
Na+ ClUrea
Albumin
Glucose
Na+ ClUrea
Albumin
Glucose
Na+ ClUrea
Albumin
Glucose
Na+ ClUrea
Albumin
Glucose
Na+ ClUrea
20
20
20
20
20