Mitochondria are the energy factories of the cells. The energy currency for the work that animals must do is the energy-rich molecule adenosine triphosphate (ATP). The ATP is produced in the mitochondria using energy stored in food. ... This is a very efficient process for using food energy to make ATP.
The seeds are enclosed because it's the plants way of protecting them.
C. Enzymes increase the rate of the chemical reactions carried out during metabolism.