AP BIOLOGY

Detailed explanation-1: -Photosynthates, such as sucrose, are produced in the mesophyll cells (a type of parenchyma cell) of photosynthesizing leaves. Sugars are actively transported from source cells into the sieve-tube companion cells, which are associated with the sieve-tube elements in the vascular bundles.

Detailed explanation-2: -After sugars are produced in photosynthesis, these sugars must be transported to other parts of the plant for use in the plant’s metabolism. Part of the pressure-flow theory is that the sucrose produced is moved by active transport into the companion cells of the phloem in leaf veins.

Detailed explanation-3: -Sucrose synthesized in green leaves is transported via the phloem, the long distance distribution network for assimilates in order to supply nonphotosynthetic organs with energy and carbon skeletons.

Detailed explanation-4: -In plants, sugars are produced through photosynthesis in leaves. The synthesized sugar molecules are transported to different tissues and organelles through a class of specialized cellular uptake transporters called SWEETs (Sugars Will Eventually Be Exported Transporters).