CBSE Class 10 Answered
The union of the scion with the stock depends upon the growing together of the cambium tissue of the two plants. This tissue is the living active cells found between the bark and the wood. It is composed of cells which are actively dividing.
The cambium and sometimes other thin-walled cells of the inner bark, form a mass called a callus (a lump of tissue with no specific organs). Both stock and scion form callus tissue. The callus tissues meet and fuse, and a new common cambium arises, uniting the cambium of the stock with that of the scion. The cambium now produces continuous layers of wood and bark, allowing translocation of food, water, and minerals to proceed without interruption between stock and scion.