Question

Define translocation.

Answer 1

Hint: In plants also substances such as water, nutrients, growth regulators, etc need to transport. Over the short distance, substances are transported through diffusion, while the vascular system will help to transport for long-distance.

Complete answer:
Translocation is the process by which plants deliver minerals, plant growth hormones, water, and organic substance over long distances throughout the plants (from leaves to other parts). Leaves produced the carbohydrates (sugar) through the process of photosynthesis, but other parts also required the sugar for their function. Due to this reason, the nutrients are translocated from sources (the area where carbohydrates are formed i.e., mature leaves) to the sink (the area where carbohydrates are needed). Examples of the sink are stem, root, fruits, developing seeds, etc. It occurs in the series of the cells called the phloem pathway. The phloem is present in the vascular bundle and is arranged in long, continuous strands which extend through the root and stem and reach to leaves as veins. It helps in the transportation of food materials. These food nutrients are translocated in the form of solutes in a solution known as phloem sap. Food nutrients include amino acids, sugar, etc. These nutrients are utilized by the various cells to support their requirements for life and they are also stored for future use. These nutrients are specially delivered to developing seeds and fruits. Apart from the phloem, the vascular bundle also consists of xylem. This is responsible for the transportation of water and dissolved minerals from the root to shoot.

Note: The direction of transport is an important aspect that needs to be considered. The rooted plants, transportation water and dissolved minerals by xylem are essentially unidirectional from root to the shoot. However, the transportation of organic and mineral nutrients undergoes multidirectional transport.