Physioex 9.0 Cell Transport Mechanisms
For Learning Centre use only
Activity 1: Simulating Dialysis (Simple Diffusion) Lab Report
Review Sheet Results
1. 2. Describe two Variables that affect the rate of diffusion.
The two variables that affect the rate of diffusion are:
A. The size of the molecule. The larger molecule will diffuse more slowly than the smaller molecule. B. The nature of plasma membrane. If the membrane is composed of lipid portion., only lipid soluble molecules can pass through while water molecules cannot.
3. Why do you think the urea was not able to diffuse through 20 MWCO? How well did the results compare with your predictions?
The urea was not able to diffuse through 20 MWCO because the size of the pores of 20 MWCO was too small to allow the large size of molecules of urea to pass through. Since, the molecular weight of urea is 60.07, the molecules of urea were too large to enter the pores of the 20 MWCO.
4. Describe the result of the attempts to diffuse glucose glucose and albumin through the 200 MWCO membrane. How well did the results compared with your predictions?
Glucose could diffuse through the 200 MWCO while albumin could not diffuse through such membrane. It was because there was difference of molecule weight between them. Glucose (C6H12O6) has a molecular weight of 180 g/mol and albumin, which is protein with 607 amino acids, each single amino acid is 135 g/mole, has a molecular weight of(607 x 135) 81945 g/mole. Since the molecular of albumin is quite larger in molecular weight compared with glucose, it is absolutely believed that albumin was not able to diffuse the 200 MWCO.
I obtained the results from the experiment supported my predictions because only glucose could diffuse through the 200 MWCO while albumin could not.
5. Put the following in order from smallest to largest molecular weight: glucose, sodium chloride, albumin, and urea.
Sodium chloride < urea < glucose < albumin.
Activity 2: Simulated Facilitated Diffusion
Activity 1: Simulating Dialysis (Simple Diffusion) Lab Report
Review Sheet Results
1. 2. Describe two Variables that affect the rate of diffusion.
The two variables that affect the rate of diffusion are:
A. The size of the molecule. The larger molecule will diffuse more slowly than the smaller molecule. B. The nature of plasma membrane. If the membrane is composed of lipid portion., only lipid soluble molecules can pass through while water molecules cannot.
3. Why do you think the urea was not able to diffuse through 20 MWCO? How well did the results compare with your predictions?
The urea was not able to diffuse through 20 MWCO because the size of the pores of 20 MWCO was too small to allow the large size of molecules of urea to pass through. Since, the molecular weight of urea is 60.07, the molecules of urea were too large to enter the pores of the 20 MWCO.
4. Describe the result of the attempts to diffuse glucose glucose and albumin through the 200 MWCO membrane. How well did the results compared with your predictions?
Glucose could diffuse through the 200 MWCO while albumin could not diffuse through such membrane. It was because there was difference of molecule weight between them. Glucose (C6H12O6) has a molecular weight of 180 g/mol and albumin, which is protein with 607 amino acids, each single amino acid is 135 g/mole, has a molecular weight of(607 x 135) 81945 g/mole. Since the molecular of albumin is quite larger in molecular weight compared with glucose, it is absolutely believed that albumin was not able to diffuse the 200 MWCO.
I obtained the results from the experiment supported my predictions because only glucose could diffuse through the 200 MWCO while albumin could not.
5. Put the following in order from smallest to largest molecular weight: glucose, sodium chloride, albumin, and urea.
Sodium chloride < urea < glucose < albumin.
Activity 2: Simulated Facilitated Diffusion