pH & Hb-Oxygen Binding

1			The oxygen dissociation curve shows that as the partial pressure of oxygen is decreased to a very low level, the amount of oxygen bound to hemoglobin:
			A)	increases.
			B)	does not change.
			C)	decreases.
2			Look at your graph. A high transmittance value ('color') indicates:
			A)	a large amount of oxygen is bound to hemoglobin.
			B)	a small amount of oxygen is bound to hemoglobin.
			C)	no oxygen is bound to hemoglobin.
			D)	nothing with respect to the amount of oxygen bound to hemoglobin.
3			A solution with a pH below 7 is said to be:
			A)	acidic.
			B)	neutral.
			C)	alkaline.
4			Decreasing the pH of the blood (making it more acidic):
			A)	moves the oxygen dissociation curve to the left.
			B)	moves the oxygen dissociation curve to the right.
			C)	has no effect on the oxygen dissociation curve.
5			Look at the curves on your graph, about one-third of the way from zero mark on the horizontal axis (a PO2 value around 50 mm Hg). Imagine a vertical line that intersects the curves.
			A)	Blood with a lower pH has a lower transmittance value (‘color').
			B)	Blood with a lower pH has the same transmittance value (‘color') as blood without DPG.
			C)	Blood with a lower pH has a higher transmittance value (‘color').
6			Look at the two curves on your graph, about one-third of the way from zero mark on the horizontal axis (a PO2 value around 50 mm Hg). Imagine a vertical line that intersects the curves.
			A)	Blood with a lower pH has more oxygen bound to hemoglobin.
			B)	Blood with a lower pH has the same amount of oxygen bound to hemoglobin.
			C)	Blood with a lower pH has less oxygen bound to hemoglobin.
7			At PO2 levels around 50 mm Hg (approximately the same PO2 value found in the tissues), a lower pH:
			A)	decreases the amount of bound oxygen; i.e., hemoglobin releases more oxygen to the tissues.
			B)	does not change the amount of bound oxygen bound; i.e., the amount of oxygen released is constant.
			C)	increases the amount of bound oxygen bound; i.e., hemoglobin releases less oxygen to the tissues.
8			Cells make hydrogen ions because they can produce:
			A)	lactic acid, which can move into the interstititial fluid and then into the plasma.
			B)	carbon dioxide, which reacts with water to form hydrogen and bicarbonate ions.
			C)	both of the above options are true.
9			Hydrogen ions bind to the beta-chains and decrease the affinity of hemoglobin for oxygen. Therefore, lowering the pH:
			A)	moves the oxygen dissociation curve to the left.
			B)	has no effect on the oxygen dissociation curve.
			C)	moves the oxygen dissociation curve to the right.
10			At the tissues, a low pH pushes the oxygen dissociation curve to the right so that:
			A)	less oxygen is released, which leaves more oxygen bound to hemoglobin.
			B)	more oxygen is released, which leaves more oxygen bound to hemoglobin.
			C)	less oxygen is released, which leaves less oxygen bound to hemoglobin.
			D)	more oxygen is released, which leaves less oxygen bound to hemoglobin.