Cell Transport Mechanisms and Permeability
Name ____________________________________________________________ Lab Time/Date ______________________________
Activity 1 Imitating Dialysis ( Simple Diffusion )
1. Describe two variables that affect the rate of diffusion. * The size of the pores of the membrane
* The size of the molecule spreading through the membrane
2. Why do you believe the carbamide was non able to spread through the 20 MWCO membrane? How good did the consequences compare with your anticipation? * Because the pores of the membrane were non big plenty * I predicted this right.
3. Describe the consequences of the efforts to spread glucose and albumin through the 200 MWCO membrane. How good did the consequences compare with your anticipation? I predicted that merely glucose would spread through it and was right. Albumin is excessively heavy to spread through that membrane. 4. Put the followers in order from smallest to largest molecular weight: glucose. Na chloride. albumen. and urea. NaCl. Urea. Glucose. Albumin
Activity 2 Simulated Facilitated Diffusion
1. Explain one manner in which facilitated diffusion is the same as simple diffusion and one manner in which it differs. -Similar – They pass through the membrane without the usage of ATP. they’re both signifiers of inactive conveyance. -Different – The solutes in facilitated diffusion base on balls through a bearer protein while the solutes pass through the membrane in simple diffusion. 2. The larger value obtained when more glucose bearers were present corresponds to an addition in the rate of glucose conveyance. Explain why the rate increased. How good did the consequences compare with your anticipation? Since there were more bearer proteins. more glucose could spread into the cell at one clip which made the procedure travel along much quicker. I predicted this right. 3. Explain your anticipation for the consequence Na+Cl? might hold on glucose conveyance. In other words. explicate why you picked the pick that you did. How good did the consequences compare with your anticipation? I said that
the rate of diffusion would diminish. which was incorrectly. because I figured that holding the NaCl would equalise the concentration gradient and do the concentration gradient and do it a slower procedure. The rate really remained unaffected because NaCl is non required for glucose in the simulation.
Activity 3 Simulating Osmotic Pressure
1. Explain the consequence that increasing the Na+Cl? concentration had on osmotic force per unit area and why it has this consequence. How good did the consequences compare with your anticipation? I predicted right in stating that the NaCl concentration would increase the force per unit area because they are straight related. intending if one increased. that means the other 1 must hold increased every bit good. 2. Describe one manner in which osmosis is similar to simple diffusion and one manner in which it is different. -Similar – Solutes can still go through through the membrane in both simple diffusion and osmosis. -Different – In diffusion. the atoms go from high concentration parts to low concentration parts. while in osmosis it crosses from a part of low solute concentration to high solute concentration. 3. Solutes are sometimes measured in milliosmoles. Explain the statement. “Water chases milliosmoles. ” Water follows the solutes ( milliosmoles ) into higher concentrated countries of solutes. intending it was traveling against the concentration gradient and “chasing the milliosmoles. ” 4. The conditions were 9 millimeters albumin in the left beaker and 10 millimeters glucose in the right beaker with the 200 MWCO membrane in topographic point. Explain the consequences. How good did the consequences compare with your anticipation? Keeping in head the past activities. I predicted right before making this activity. The glucose diffused through to the left beaker organizing equilibrium. which created osmotic force per unit area on the left side. The albumen can non suit through that membrane so it didn’t reach equilibrium.
Activity 5 Simulating Active Transport
1. Describe the significance of utilizing 9 mM Na chloride inside the cell and 6 millimeter K chloride outside the cell. alternatively of other concentration ratios. Because the sodium-potassium pump needs a 3:2 ratio to map. significance once the concentration of the KCl runs out so the NaCl can non
map either. 2. Explain why there was no Na transport even though ATP was present. How good did the consequences compare with your anticipation? I predicted incorrect with this activity because I said that the Na+ would be maximally transported. I know now that although in the presence of ATP. the pump still can non work without any K. 3. Explain why the add-on of glucose bearers had no consequence on Na or K conveyance. How good did the consequences compare with your anticipation? I besides predicted falsely on this one because I did non recognize that the glucose bearers don’t need ATP to work so they were still at the clemency of how much K there was in the sodium-potassium pump. I thought that there would be easier entree into the cell for the Na and K cells. 4. Make you believe glucose is being actively transported or transported by facilitated diffusion in this experiment? Explain your reply. Facilitated diffusion because it is traveling with the concentration gradient and the glucose bearers don’t require ATP to transport the glucose.