Vascular plants have cellular structures that provide for the movement of water and food throughout the plant. The plant tissue xylem carries water while phloem carries food in the form of sugars. Minerals dissolve in water in the soil and are absorbed by the roots along with the water, making the minerals available to the plant. Water is carried to the leaves, where photosynthesis converts solar energy, minerals, carbon dioxide and water into sugar.
The primary mover of water throughout a plant, Xylem is made up of specialized cells that grow end to end. All the structures of the plant from the rootlets to the leaves contain xylem. Water is drawn up through the plant by water surface tension. The bipolar water molecules form bonds with each other, and as one molecule evaporates from a leaf, it pulls the molecule below it up, which pulls the one below it up.
Phloem distributes the sugars manufactured by photosynthesis in the leaves. Some food is distributed to the roots where it is stored. Actively growing portions of the plant also receive a portion of the food in order to build new cells. Finally, the reproductive parts of the plant receive food in order to reproduce.
Tiny hairlike structures called rootlets have porous cell walls that allow water, and minerals dissolved in the water, to be absorbed by the plant. Water moves through the rootlets to the roots, up the stems and into the leaves.
Roots anchor the plant, pass water to the stem from the rootlets and store food for future use. Some plants also reproduce by means of specialized roots. These specialized roots may be bulbs, corms or tubers.
Stems lift the leaves into the sunlight, allowing photosynthesis to take place. Different types of plants have different types of stems. Annuals have relatively weak stems that only last a single season. Long lived trees and shrubs have heavy wooden stems that lift the foliage high in the air.
Leaves are the food factories of the plant. A chemical process called photosynthesis converts water and carbon dioxide into carbon molecule chains called sugars. Carbon is taken from the carbon dioxide and combined with water using the energy from sunlight. The resulting molecule is a simple sugar. A byproduct of photosynthesis, oxygen molecules are released through pores in the leaves.
Many plants reproduce through flowers, which manufacture seeds and allow for sexual reproduction. Some plants produce spores, similar in certain ways to seeds. Still others create copies of the themselves, which grow into plants that are genetically identical to the parent plants. Finally, some plants utilize multiple methods of reproduction such as producing seeds and growing new plants from root offshoots.