Phloem is often described as a plant's delivery route out of the leaves. What does phloem carry away from a leaf that has been photosynthesising?

الشرح

A lit leaf builds sugar, and phloem is the route that carries that sugar in solution to parts of the plant that cannot build any for themselves, such as roots and ripening fruits. Water travels in the opposite tissue and arrives at the leaf rather than leaving it, so naming water here reverses the whole journey.