C) a system is a set of parts that function together as a whole
Many living organisms respond to things in the environment called Stimuli.
Mechanical digestion is the breaking down of food into smaller pieces physically. Mechanical digestion begins in the mouth as the food is chewed.
but in the case of chemical digestion, it breaks the food into simpler nutrients that can be used by the cells. Chemical digestion begins in the mouth when food mixes with saliva.
for more refer to this:
Hope this helped
and ur welcm
The nutrients are grams gram gram