To determine whether each item is a reactant or a product in the process of cellular respiration, let's examine their roles individually:
1. Glucose:
- Cellular respiration begins with glucose. The process of cellular respiration involves breaking down glucose molecules to produce energy in the form of ATP (adenosine triphosphate).
- Glucose is the starting material or input for cellular respiration.
- Therefore, glucose is a reactant.
2. Carbon Dioxide (CO₂):
- During cellular respiration, glucose and oxygen react to form carbon dioxide, water, and energy.
- Carbon dioxide is released as a waste product during the breakdown of glucose.
- Therefore, carbon dioxide is a product of cellular respiration.
3. Water (H₂O):
- Water is produced during the later stages of cellular respiration, specifically during the electron transport chain when oxygen combines with protons and electrons.
- As such, water is a byproduct of the reactions that take place during cellular respiration.
- Therefore, water is a product of cellular respiration.
Summarizing:
- Glucose: Reactant
- Carbon Dioxide (CO₂): Product
- Water (H₂O): Product
Thus, the detailed roles in cellular respiration for these items are:
- Glucose: Reactant
- Carbon Dioxide (CO₂): Product
- Water (H₂O): Product