1. Which statement most accurately describes the process of respiration?
Select one:
a. It occurs only in plants during the daylight hours and usually involves the exchange of gases.
b. It occurs only in plants during the daylight hours and involves the taking in of preformed organic molecules.
c. It occurs continuously in the cells of all organisms and involves the synthesis of carbohydrate molecules.
d. It occurs continuously in the cells of all organisms and often involves an exchange of gases.