3) What is Photosynthesis?
As stated previously, plants grow by converting sunlight, water and carbon dioxide into food for itself and release oxygen into the world. When our faith is healthy it should be going through the same process of growth, and now see how this connects with how trees grow.
Sun
In Botanical Epistemology, the sun represents God, specifically Jesus, which is experienced in prayer, worship and praise. Therefore just like sunlight is not only absorbed by the tree, but it is also reflected back, we do the same with our faith, in our understanding and our actions.
Water

Carbon Dioxide and Oxygen
Trees provide invaluable service of converting carbon dioxide that animals release and converting it into oxygen that they can breath in. From an animal perspective, carbon dioxide is harmful, but for a trees it is essential. This directly parallels any suffering that we experience. While suffering looks harmful to the rest of the world, it is beneficial and even essential for a healthy faith. More than this: our faith converts our suffering into a example which proclaims the message of peace to the world, that Jesus did, this symbolizes the oxygen that the tree releases.