NEET 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: -Phloem are tissues that look like tubes. They transport sugars throughout the plant and supply it to tissues like roots, flowers and fruits that depend on this sugar to grow. Think of them like the veins in our body that move blood. Moving sugars from cells in the leaves to cells in the phloem is difficult for plants.

Detailed explanation-4: -A high hydrostatic pressure is generated in the sieve tubes of the collection phloem and water from the xylem is attracted. Sucrose, RFOs and polyols are transported in the sieve tubes to the sink organs in the transport phloem.

Detailed explanation-5: -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.