A solute, X, is placed in compartment A of a two compartment container and allowed to diffuse to compartment B and attain diffusion equilibrium. At that point in time,
A. there will be no further movement of any solute molecules between compartments.
B. solutes will be moving in both directions equally.
C. solutes will only continue to move from A to B.
D. solutes will only continue to move from B to A.
E. the concentration in compartment B will be much higher than that in compartment A.
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Question 2) Equal amounts of two solutes, A and B, are placed into the same beaker of water at the same time. Solute A reaches diffusion equilibrium faster than solute B. What is the most likely explanation for this observation?
A. The temperature was greater for solute A than solute B.
B. The concentration gradient for A was greater than B.
C. Solute A is smaller than solute B.
D. Solute A traveled a shorter distance than solute B.
E. Solute B is more soluble in water than solute A.
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Question 3) Which of the following would decrease the net flux of a penetrating solute into a cell?
A. increasing the permeability constant for that solute
B. decreasing the temperature
C. increasing the concentration of the solute in the extracellular fluid
D. increasing the area of the cell membrane
E. decreasing the thickness of the membrane
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Question 4) Which of the following statements regarding the diffusion of a nonpolar solute X across a cell membrane is correct?
A. At equilibrium the net flux of X across the cell membrane is zero.
B. At equilibrium, X will cease moving across the cell membrane.
C. Solute X will be unable to reach equilibrium because it is nonpolar.
D. Solute X will reach equilibrium, but the concentration will be much higher on the inside of the cell because of the smaller volume.
E. At equilibrium, movement of X across the membrane will be much faster in one direction than in the other.
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Question 5) Which is TRUE regarding diffusion?
A. It depends upon the random motion of molecules.
B. It results in net movement of molecules from regions of low concentration to regions of high concentration.
C. It is the principal mechanism by which molecules are moved over large distances in the body.
D. It requires energy in the form of ATP.
E. It requires integral membrane proteins to occur.
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Question 6) Which of the following statements regarding the structure and function of cell membranes is correct?
A. The phospholipid bilayer is arranged so that the hydrophilic heads of the phospholipid molecule face the extra- and intracellular fluids.
B. Some proteins integrated into the membrane serve as channels for the passage of nonpolar molecules through the membrane.
C. Peripheral membrane proteins function as channels associated with transport of ions through the membrane.
D. Cholesterol molecules function to transport ions from one side of the plasma membrane to the other.
E. The plasma membrane is a layer of phospholipid molecules with their hyrophilic head groups in contact with the extracellular solution and the hydrophobic tail groups in contact with the intracellular solution.
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Question 7) Fat-soluble vitamins are required for health because they act as coenzymes.
Indicate whether the statement is true or false.
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Question 8) An essential nutrient is one necessary for good health that may or may not be synthesized by the body.
Indicate whether the statement is true or false.
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Question 9) Removal of the amino group from an amino acid is necessary before the amino acid can be metabolized for energy.
Indicate whether the statement is true or false.
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Question 10) Human beings can synthesize all twenty amino acids the body must have.
Indicate whether the statement is true or false.
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