In root-tubers, there are no nodes and internodes or reduced leaves. Root tubers have one end called the proximal end, which is the end that was attached to the old plant; this end has crown tissue that produces buds which grow into new stems and foliage. The other end of the root tuber is called the distal end, and it normally produces unmodified roots. In stem tubers the order is reversed, with the distal end producing stems. Tuberous roots are biennial in duration: the first year the plant produces root-tubers, and at the end of the growing season, the plant shoots often die, leaving the newly generated tubers. The next growing season, the root-tubers produce new shoots. As the shoots of the new plant grow, the stored reserves of the root-tuber are consumed in the production of new roots, stems, and reproductive organs; any remaining root tissue dies concurrently to the plant's regeneration of next generation of root-tubers.