Simulated Facilitated Diffusion

PhysioEx Lab Report Exercise 1: Cell Transport Mechanisms and Permeability Activity 2: Simulated Facilitated Diffusion Name: Date: 15 September 2020 Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1 Molecules need a carrier protein to help them move across a membrane because You correctly answered: they are lipid insoluble or they are too large. 2 Which of the following is true of facilitated diffusion? You correctly answered: Movement is passive and down a concentration gradient. 3 Examples of solutes that might require facilitated diffusion include You correctly answered: all of the above. 4 Which of the following would not affect the rate of facilitated diffusion? You correctly answered: the amount of intracellular ATP. Experiment Results Predict Questions 1 Predict Question 1: What effect do you think increasing the number of protein carriers will have on the glucose transport rate? Your answer: The glucose transport rate will increase. 2 Predict Question 2: What effect do you think adding Na Cl will+have on the glucose transport rate? Your answer: The glucose transport rate will decrease. Stop & Think Questions 1 What happened to the glucose transport rate when the glucose concentration was increased from 2 mM to 8 mM? You correctly answered: The glucose transport rate increased. 2 Describe the conditions that resulted in the fastest rate of glucose transport. You correctly answered: 700 glucose carrier proteins and 8 mM glucose. 3 Why do you think equilibrium wasn't reached? You correctly answered: The membrane proteins were saturated. Experiment Data Run Number Solute Start Conc. L (mM) 1 Na + Cl - 1 Glucose 2 Na + Cl - 2 Glucose 3 Na + Cl - 3 Glucose 4 Na + Cl - 4 Glucose 5 Na + Cl - 0.00 5 Glucose 10.00 6 Na + Cl - 0.00 6 Glucose Start Conc. R (mM) 0.00 2.00 0.00 0.00 0.00 8.00 0.00 0.00 0.00 2.00 0.00 0.00 0.00 8.00 2.00 0.00 0.00 0.00 0.00 2.00 0.00 Carriers 500 500 500 500 700 700 700 700 100 100 700 700 Post-lab Quiz Results You scored 75% by answering 3 out of 4 questions correctly. 1 What variable(s) increased the rate of facilitated diffusion of glucose? Your answer: increasing the number of membrane carriers. Correct answer: increasing the concentration of glucose and increasing the number of membrane carriers. 2 For facilitated diffusion, increasing the concentration of glucose on one side of the membrane is the same as You correctly answered: making the concentration gradient steeper. 3 When all of the membrane carriers are engaged, or busy, we say they are You correctly answered: saturated. Rate (mM/sec) 0.0000 0.0008 0.0000 0.0023 0.0000 0.0010 0.0000 0.0031 0.0000 0.0017 0.0042 0.0010 4 Na +Cl - had no effect on glucose transport because You correctly answered: sodium is not required for glucose transport in the simulation. Review Sheet Results 1 Explain one way in which facilitated diffusion is the same as simple diffusion and one way in which it is different from simple diffusion. Your answer: Facilitated diffusion and simple diffusion are the same because they both move solutes through membranes. They way they differ is that facilitated diffusion requires a protein to move the solute, while simple diffusion does not. 2 The larger value obtained when more glucose carriers were present corresponds to an increase in the rate of glucose transport. Explain why the rate increased. How well did the results compare with your prediction? Your answer: Glucose transport rate increased as I predicted, because the number of proteins was higher, there was a larger number of transport proteins available to transport glucose between the beakers and to the other side. + 3 Explain your prediction for the effect Na Cl might have on glucose transport. In other words, explain why you picked the choice that you did. How well did the results compare with your prediction? Your answer: Sodium is not needed in the transport of glucose, all that it did was add a higher concentration of NaC+Cl-, but did not aid the glucose in any way.