In the process some of the mass of the hydrogen atoms is converted into energy in the form of light. The same process occurs in thermonuclear (fusion) bombs. In the Sun the process occurs in a controled manner. In a bomb it happens all at once in a big chain-reaction explosion.
Phloem. Definition. noun. A tissue in a vascular plant that functions primarily in transporting organic food materials (e.g. sucrose) from the photosynthetic organ (leaf) to all the parts of the plant.
(2) companion cell. (3) phloem fibers. (4) phloem parenchyma. The tissue is responsible for translocation, a process in plants responsible for transporting the photosynthate materials to all parts of a vascular plant. Phloem may be classified into the following based on the stage or origin of growth 1  : primary phloem. 2  secondary phloem.