In which location would you expect the oxygen concentration to be the lowest?

The location where oxygen concentration is lowest is : Within tissues ( D)

The oxygen concentration in the body is higher in organs closer to the heart and organs directly involved in respiratory activities, organs such as lungs and the blood and environment surrounding these organs will have a high concentration of oxygen. while organs farther from the lungs and heart such as the tissues will have a lower concentration of oxygen.

Hence we can conclude that The location where oxygen concentration is lowest is : Within tissues ( D)

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The options related to your question is missing attached below are the missing options

a. blood b. environment c. lungs d. within tissues e. heart

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.