The inorganic solute substances are carried in the xylem vessels with the ascending sap of water in the transpiration stream. Root endodermis is covered with the layer of suberin, and they allow the passage of ions in one direction only. Endodermal cell transport proteins are control points where plants can adjust the quantity and type of solutes that reach the xylem according to their variable requirement. The upward movement usually occurs through the xylem, while bidirectional movement occurs through the phloem.Ħ. Every cell has many transport proteins in its plasma membrane, including endodermal cells some solutes cross the membrane but restrict others.
These specific proteins actively pump ions from the soil into the cytoplasms of the epidermal cells of root hairs. Passive transport occurs through mass flow or bulk flow system and diffusion, while active transport occurs due to specific proteins in the membrane of root hair cells. Hence, ions are absorbed from the soil by both passive and active transport.Ĥ. Some ions can also be absorbed passively into the epidermal cells of roots by mass flow and diffusion. The active uptake of ions is responsible for water potential gradient in roots and, therefore, helps in water uptake by osmosis. This movement of ions from soil to the root’s interior is against a concentration gradient and requires energy.ģ. Due to the above reasons, most minerals enter the root by active absorption into the cytoplasm of epidermal cells.
So, all minerals cannot be absorbed passively by roots.Ģ. (b) Mineral concentrations in soil are usually lower than those in roots. (a) Minerals are present in the soil as charged ions that cannot move across the cell membranes. Most of the minerals are absorbed actively by the roots, unlike water and some minerals. Hydrogen for carbon fixation is made available by water, and the remaining minerals are obtained from the soil. They get carbon from carbon dioxide and receive oxygen from the atmosphere. Plants obtain these mineral elements from the atmosphere, soil and water. In addition to the carbohydrates produced or generated in photosynthesis, plants also require certain minerals. Uptake and Transport of Mineral Nutrients Frequently Asked Questions (FAQs) on Translocation of Solutes.Mechanism of Translocation through Phloem.Translocation and Storage of Food in Plants.Uptake and Transport of Mineral Nutrients.