If the molecular weight of urea is 60.07, will urea diffuse through a 20 MWCO membrane?
answer
No
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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
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glucose and albunim are both too large to pass
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The rate of diffusion for urea
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is slower than that for sodium because urea is a larger molecule
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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?
answer
both glucose and albumin
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The effect of increasing the concentration of sodium chloride from 9 mM to 18 mM in the left beaker was to
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increase the rate of diffusion.
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Describe the difference between the rate of diffusion seen for sodium and urea.
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Urea diffused more slowly because it is larger than sodium.
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Which of the following solutes did not pass through any of the membranes?
albumin
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albunim
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When diffusion stops, we say the solution has reached
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Equilibrium
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Describe two variables that affect the rate of diffusion?
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size of material and concentration of gradient
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Why do you think the Urea was not able to diffuse through the 20MWCO membrane?
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because urea was too big to pass through the 20 MWCO membrane
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Describe the result of the attempt to diffuse glucose and albumin through the 200 MWCO membrane?
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the glucose diffused through the 200MWCO membrane, while there was no diffusion of albumin.
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Put the following in order from the smallest to largest molecular weight: glucose, sodium chloride, albumin, urea.
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sodium chloride, urea, glucose, albumin
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Molecules need a carrier protein to help them move across a membrane because
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they are lipid insoluble or they are too large.
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Which of the following is true of facilitated diffusion?
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Movement is passive and down a concentration gradient.
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Examples of solutes that might require facilitated diffusion include
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all of the above : glucose, sodium, and potassium
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Which of the following would not affect the rate of facilitated diffusion?
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the amount of intracellular ATP
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What happened to the glucose transport rate when the glucose concentration was increased from 2 mM to
8 mM?
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The glucose transport rate increased.
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What effect do you think increasing the number of protein carriers will have on the glucose transport rate?
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Increasing the number of protein carriers will increase the glucose transport rate.
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Describe the conditions that resulted in the fastest rate of glucose transport.
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700 glucose carrier proteins and 8 mM glucose
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Why do you think equilibrium wasn't reached?
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The membrane proteins were saturated.
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What effect do you think adding Na+Cl- will have on the glucose transport rate?
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Adding Na+Cl- will have no effect on the glucose transport rate because of the carrier is only transporting glucose through the membrane
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What variable increased the rate of facilitated diffusion of glucose?
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a. increasing the concentration of glucose
and
b. increasing the number of membrane carriers
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For facilitated diffusion, increase the concentration of glucose on one side of the membrane is the same as
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making the concentration gradient steeper
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Na+ Cl- had no effect on the transport bc
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sodium isnt required for glucose transport in the simulation
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Explain one way in which facilitated diffusion is the same as simple diffusion and one way in which it differs.
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both are passive diffusion that are from high concentration gradient to a low concentration gradient. facilitated differs from simple because it requires a carrier protein to diffuse
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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.
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The rate increased because there is more room and surface area increases relative to glucose
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What effect do you think adding Na+Cl- will have on the glucose transport rate?
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Increasing the NaCl will increase the osmotic pressure. because water needs to diffuse to the higher concentration gradient until equilibrium is reached.
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Which of the following is true of osmosis?
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It is a type of diffusion
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Which of the following occurs when a hypertonic solution is added to cells?
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The cells will shrink
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The variable that affects osmotic pressure is
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the concentration of nondiffusing solutes.
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The net movement of water would be into the cell in a
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hypotonic solution
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What effect do you think increasing the Na+Cl- concentration will have?
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Increasing the Na+Cl- concentration will increase the osmotic pressure.
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Why do you think there is no pressure change?
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Sodium is able to diffuse through the pores
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Why do you think there was no pressure change?
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There is no net movement of water because the solute concentrations are the same
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If you double the concentration of a nondiffusible solute that is on one side of a membrane, the osmotic pressure will
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double
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Which membrane disallows passage of Na?Cl??
- 20 MWCO
- 50 MWCO
- 100 MWCO
- 200 MWCO
answer
20 MWCO
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When a solute is able to diffuse through a membrane
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an equilibrium is reached
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Water diffuses
- against its concentration gradient
- away from solutes
- toward solutes
- utilizing ATP
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away from solutes
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Filtration is a process that
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is passive
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Filtration is dependent upon a
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hydrostatic pressure gradient
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Filtrate
- includes fluids
- includes solutes
- passes through the filter
- all
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all
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An important site of human bodily filtration is
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kidneys
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The reason none of the solutes were present in the filtrate was that
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The solutes were all too large to pass through
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What effect will increasing the pore size of the filter have on the filtration rate?
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The filtration rate will increase.
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What will happen if you increase the pressure above the beaker (the driving pressure)?
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The filtration rate will increase.
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What does an increase in the driving pressure correspond to in the body?
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An increase in blood pressure.
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After filtration, substances that pass through the filter are called the filtrate, which includes
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All of the above - solvent, solutes, and water.
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The top beaker in the simulation corresponds to
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The blood capillary.
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Why was there not 100% recovery of the Na+Cl- solute with any of the membranes?
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Some of the solute remained on the membrane filter.
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An increase in blood pressure would probably initially ___________________ filtration in the kidneys.
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increase the rate of
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The movement of sodium and potassium maintained by the Na+-K+ pump
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requires energy and is against a concentration gradient
