Varying Extracellular Concentration

1			The membrane of red blood cells, like most other cells in your body, has
			A)	numerous open sodium channels; more than for any other ion.
			B)	many open sodium channels.
			C)	very few open sodium channels.
2			When a red blood cell is placed in hypertonic (very concentrated) solutions of NaCl:
			A)	sodium ions rush into the cell, down the concentration gradient.
			B)	sodium ions rush out of the cell, down the concentration gradient.
			C)	sodium ions may enter the cell, but are pumped out by the Na/K-ATPase pump.
			D)	sodium ions may leave the cell, but are pumped back in by the Na/K-ATPase pump.
3			When a red blood cell is placed in hypertonic (very concentrated) solutions of NaCl:
			A)	water leaves the cell, and the cell swells.
			B)	water leaves the cell, and the cell shrinks.
			C)	water enters the cell, and the cell swells.
			D)	water enters the cell, and the cell shrinks.
4			Low transmittance values indicate that the red blood cells have lost water and have shrunk. According to your data, what range of concentrations of NaCl produced this effect?
			A)	200 to 240 mM.
			B)	120 to 160 mM.
			C)	0 to 200 mM.
5			When a red blood cell is placed in hypotonic (very dilute) solutions of NaCl:
			A)	water leaves the cell, and the cell shrinks.
			B)	water leaves the cell, and the cell swells.
			C)	water enters the cell, and the cell shrinks.
			D)	water enters the cell, and the cell swells.
6			When a red blood cell is placed in hypotonic (very dilute) solutions of NaCl:
			A)	sodium ions rush into the cell, down the concentration gradient.
			B)	sodium ions rush out of the cell, down the concentration gradient.
			C)	some sodium ions may leave the cell.
			D)	some sodium ions may enter the cell.
7			High transmittance values indicate that the red blood cells have swollen or burst. According to your data, what concentrations of sodium chloride produced this effect?
			A)	0 to 120 mM.
			B)	150 to 180 mM.
			C)	200 to 250 mM.
8			When a red blood cell is placed in isotonic solutions of NaCl:
			A)	water enters the cell, and the cell swells and bursts.
			B)	water neither leaves nor enters the cell; the cell neither swells nor shrinks.
			C)	water leaves the cell, and the cell shrinks.
9			Look at your data. Transmittance values that are intermediate between those seen in dilute and concentrated solutions were found in NaCl solutions:
			A)	between 0 and 100 mM.
			B)	between 140 and 180 mM.
			C)	between 200 and 240 mM.
10			Some NaCl solutions gave transmittance values that were intermediate between those seen in dilute and concentrated solutions. In these solutions:
			A)	water entered the cell, and the cell swelled and burst.
			B)	water neither left nor entered the cell; the cell neither swelled nor shrank.
			C)	water left the cell, and the cell shrank.