Question

A biologist ground up some plant leaf cells and then centrifuged the mixture to fractionate

the organelles. Organelles in one of the heavier fractions could produce ATP in the light,


while organelles in the lighter fraction could produce ATP in the dark. The heavier and


lighter fractions are most likely to contain, respectively,

Answer 1

Chloroplasts (heavy) and Mitochondria (Light)

Step-by-step explanation

Light dependent reactions of photosynthesis (in chloroplasts) produce ATP only when exposed to light. Mitochondria respirates and produces ATP regardless.