When the Sun's energy moves through space, it reaches Earth's atmosphere and finally the surface. This radiant solar energy warms the atmosphere and becomes heat energy. This heat energy is transferred throughout the planet's systems in three ways: by radiation, conduction, and convection.
Answer:
While plant cells have chloroplasts to photosynthesize, they also require ATP for cellular functions, and do use oxygen to break down some of the sugar they produce in order to generate that ATP. They need mitochondria for this.
In particular, at night when there is no light, plants undergo cellular respiration since there is no sunlight to photosynthesize.
They do, however, produce far more sugar and oxygen through photosynthesis than they use up in respiration.
The carbon that plants need for photosynthesis comes from (carbon dioxide gas in the atmosphere)
