The primary purpose of respiration in plants is to metabolize sugar for energy.

The primary purpose of respiration in plants is to metabolize sugar for energy.

• A. To produce glucose from carbon dioxide
• B. To store energy as starch
• C. To absorb water and minerals
• D. To metabolize sugar for energy

Answer: (D)

The main idea is that respiration in plants is about getting energy from sugar to power the cell. In plant cells, glucose produced by photosynthesis is oxidized in mitochondria through glycolysis, the Krebs cycle, and the electron transport chain, releasing energy stored as ATP along with CO2 and water. That ATP fuels activities like growth, transport, and active processes. Photosynthesis, on the other hand, is how plants make and store energy—building glucose and storing it as starch using light energy and CO2. Absorbing water and minerals is a function of roots, not respiration. So the statement that respiration’s primary purpose is to metabolize sugar for energy best captures what respiration does.

The main idea is that respiration in plants is about getting energy from sugar to power the cell. In plant cells, glucose produced by photosynthesis is oxidized in mitochondria through glycolysis, the Krebs cycle, and the electron transport chain, releasing energy stored as ATP along with CO2 and water. That ATP fuels activities like growth, transport, and active processes. Photosynthesis, on the other hand, is how plants make and store energy—building glucose and storing it as starch using light energy and CO2. Absorbing water and minerals is a function of roots, not respiration. So the statement that respiration’s primary purpose is to metabolize sugar for energy best captures what respiration does.