Sickle-cell disease causes hemoglobin proteins to become altered. What direct effect does this have on red blood cells?
A. Red blood cells swell up, allowing fewer to flow through tiny capillaries and reducing blood flow.
B. Red blood cells become sickle-shaped, clumping up and blocking blood flow in capillaries.
C. Red blood cells shrivel up, causing too many of them to flow through capillaries at once, increasing blood pressure.
D. Red blood cells become sickle-shaped, resulting in them carrying increased oxygen to body cells. Hyperoxia results.
Answer: B
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A) step 1
B) step 2
C) step 3
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