Final answer:
Glucose for cellular respiration comes from the food we eat. Plants can make their own glucose through photosynthesis, but animals obtain glucose by eating carbohydrates. During cellular respiration, glucose is converted by cells into usable energy (ATP).
Step-by-step explanation:
Glucose for cellular respiration comes from the food we eat.
Plants are able to make their own glucose through photosynthesis, but animals cannot. Animals obtain glucose by eating carbohydrates.
During cellular respiration, glucose is converted by cells into energy that is usable by the cell (ATP).