All the different parts of a tree are made using the glucose produced by photosynthesis

This diagram shows parts of the kahikatea tree (leaves, seeds, roots and trunk) as an example.

Image acknowledgements: Kahikatea trunk, Cheryl Dawson, CC BY-NC 4.0; Seeds, Peter de Lange, Public Domain; Leaves, Jane Gosden, CC BY-NC 4.0; Roots, Annfr, CC BY-NC 4.0. All sourced from iNaturalistNZ. Kahikatea illustration, Matt Stribey.