The Following Questions Refer to the Data Shown Below Figure 421
-How Is Most of the Carbon Dioxide Transported by Entering

The following questions refer to the data shown below.
Blood entering a capillary bed of a vertebrate was measured for the pressures exerted by various factors.
$$\begin{array} { l c c } & \begin{array} { c } \text { Arterial End of } \\\text { Capillary Bed }\end{array} & \begin{array} { c } \text { Venous End of } \\\text { Capillary Bed }\end{array} \\\hline \text { Hydrostatic pressure } & 10 \mathrm {~mm} \mathrm { Hg } & 14 \mathrm {~mm} \mathrm { Hg } \\\text { Osmotic pressure } & 26 \mathrm {~mm} \mathrm { Hg } & 26 \mathrm {~mm} \mathrm { Hg } \\\mathrm { PO } _ { 2 } & 100 \mathrm {~mm} \mathrm { Hg } & 42 \mathrm {~mm} \mathrm { Hg } \\\mathrm { PCO } _ { 2 } & 40 \mathrm {~mm} \mathrm { Hg } & 46 \mathrm {~mm} \mathrm { Hg }\end{array}$$
Figure 42.1
-How is most of the carbon dioxide transported by the blood in humans?

A) bicarbonate ions in the plasma
B) CO2 attached to hemoglobin
C) carbonic acid in the erythrocytes
D) CO2 dissolved in the plasma
E) bicarbonate attached to hemoglobin