Transpiration: ↑ the process by which water vapor is released from the surfaces of plants, flowers, fruits, or vegetables. Respiration: ↑ the process used by plants to generate energy. Oxygen and stored sugars are used and carbon dioxide and water are produced. Plant respiration is the process of plants using up the sugars made through photosynthesis and turning them into energy for growth, reproduction, and other life processes. Plant respiration involves taking in oxygen and releasing it as carbon dioxide into the atmosphere.