Biology - Transportation in Plants

Introduction

• The plants have low energy needs, as they use relatively slow transport systems.

• Plant transport systems move energy from leaves and raw materials from roots to all their parts.

• The xylem (tissue) moves water and minerals obtained from the soil to all other parts of the plants.

• The phloem (tissue) transports products of photosynthesis from the leaves (where they are synthesized) to other parts of the plant.

Movement of Water in Plants

• Water moves into the root from the soil and then steady it moves into the root xylem, creating a column of water, which is progressively pushed upwards.

• Evaporation of water molecules from the cells of a leaf (see the image given above) creates a suction process, which pulls water from the xylem cells of roots; this process keeps going on.

• The loss of water in the form of vapor from the leaves (i.e. aerial parts) of the plant is known as transpiration.

• Transpiration, likewise, helps in the absorption and upward movement of water and minerals dissolved in it from roots to the leaves.

• Transpiration also helps in the temperature regulation (in plants).

• The transport of soluble products of photosynthesis is known as translocation, which occurs in the part of the vascular tissue known as phloem.

• Along with photosynthesis products, the phloem also transports amino acids and other substances, which are ultimately delivered to roots, fruits, seeds, and to growing organs.