Cell Transport Mechanisms and Permeability Worksheet Essay Example
Exercise 1: Cell Transport Mechanisms and Permeability Worksheet.
Simple Diffusion
Activity 1: Simulating Simple diffusion 1. What is the molecular weight of Na+? 22.99 2. What is the molecular weight of Cl-? 35.45 3. Which MWCO dialysis membranes allowed both of these ions through? 50, 100, 200 4. Which materials diffused from the left beaker to the right beaker? Na+/Cl-, Urea, Glucose 5. Which did not? Why? Albumin did not diffuse from the left to the right beaker. The conclusion is that Albumin is a polar substance. Polar substances have a much lower solubility in the membrane phospholipids. Certain compounds that are intermediates of metabolism are not usually allowed through the membrane, as they are often ionized and contain groups such as phosphate.
Activity 2: Simulating Dialysis 6. What happens to the urea concentration in the left beaker (the patient)? The Urea reaches an equilibrium at 17 min of 5.000(mM). Essentially the Urea in the left beaker dropped from 10.00 to 5.00. 7. Why does this occur? Normally, dialysis machines are set to run so the blood is subjected to diffusion twice, and urea is reduced by 75% rather than 50%. Excess water is drawn from the patient, who has no other way to dispose of excess fluid.
Facilitated Diffusion
Activity 3: Facilitated Diffusion 8. At a given glucose concentration, how does the amount of time it takes to reach equilibrium change with the number of carriers used to “build” the membranes? The higher the Glucose Carriers that where built the quicker the diffusion rate for the glucose concentration. 9. Does the diffusion rate of Na+/Cl- change with the number of receptors? No 10. What is the mechanism of the Na+/Cl- transport? Facilitated Diffusion 11. If you put the same amount of glucose in the right beaker as in the left, would you be able to observe any diffusion? No diffusion was observed 12. Does being unable to observe diffusion necessarily
Simple Diffusion
Activity 1: Simulating Simple diffusion 1. What is the molecular weight of Na+? 22.99 2. What is the molecular weight of Cl-? 35.45 3. Which MWCO dialysis membranes allowed both of these ions through? 50, 100, 200 4. Which materials diffused from the left beaker to the right beaker? Na+/Cl-, Urea, Glucose 5. Which did not? Why? Albumin did not diffuse from the left to the right beaker. The conclusion is that Albumin is a polar substance. Polar substances have a much lower solubility in the membrane phospholipids. Certain compounds that are intermediates of metabolism are not usually allowed through the membrane, as they are often ionized and contain groups such as phosphate.
Activity 2: Simulating Dialysis 6. What happens to the urea concentration in the left beaker (the patient)? The Urea reaches an equilibrium at 17 min of 5.000(mM). Essentially the Urea in the left beaker dropped from 10.00 to 5.00. 7. Why does this occur? Normally, dialysis machines are set to run so the blood is subjected to diffusion twice, and urea is reduced by 75% rather than 50%. Excess water is drawn from the patient, who has no other way to dispose of excess fluid.
Facilitated Diffusion
Activity 3: Facilitated Diffusion 8. At a given glucose concentration, how does the amount of time it takes to reach equilibrium change with the number of carriers used to “build” the membranes? The higher the Glucose Carriers that where built the quicker the diffusion rate for the glucose concentration. 9. Does the diffusion rate of Na+/Cl- change with the number of receptors? No 10. What is the mechanism of the Na+/Cl- transport? Facilitated Diffusion 11. If you put the same amount of glucose in the right beaker as in the left, would you be able to observe any diffusion? No diffusion was observed 12. Does being unable to observe diffusion necessarily