Hereditary spherocytosis (HS) = disorder of red blood cells that causes cells to be smaller & spherical. Average diameter of normal red blood cells = 7.2μm, & average diameter of red blood cells in a person w/ HS = 6.7μm. Normal red blood cell = average surface area of 136μm2 & average volume of 91μm3.
Provide accurate calculation of surface area to volume ratio of HS red blood cell, as well as a prediction of its effect on efficient transferring of oxygen compared to normal red blood cell?
A The ratio is 0.45 , and the cells are more efficient at transferring oxygen.
B The ratio is 1.12, and the cells are less efficient at transferring oxygen.
C The ratio is 0.89, and the cells are less efficient at transferring oxygen.
D The ratio is 141, and the cells are more efficient at transferring oxygen.
Answer C
Correct. The correct calculation of the surface area to volume ratio of the HS cell is 0.89. This ratio is less than the ratio found in a normal red blood cell, 1.49, so the cell would be less efficient at transferring oxygen.