Question

What are the components of the transport system in highly organized plants?

Answer 1

Hint: The highly organized plants are those that have properly differentiated plant parts like stems, roots, flowers, etc. They have conducting tissues in them. These conducting tissues help in the transport of water, nutrients, and food throughout the plant body. So, they constitute the transport system of highly organized plants.

Complete answer:
The highly organized plants or complex plants are those that have well-developed transport or conducting tissues like xylem and phloem.
-The transport system in plants includes two major conducting tissues that are xylem and phloem. Other parts included in this system are roots and stomata.
-The xylem consists of narrow vessels that connect the roots to the leaves. Water, minerals, and nutrients from the soil are transported to the plant parts by xylem. It is a lignified tissue composed of xylem parenchyma and xylem fibers, tracheids, and vessels.
-The water flows through vessels by the transpiration pull created by the evaporation process from leaves. The flow of water, nutrients, and minerals is always unidirectional. This means that contents move from soil towards the aerial parts of the plant.

-The phloem on the other hand is a non-lignified tissue. The structure of the phloem consists of phloem parenchyma and phloem fibers, sieve tubes, and companion cells. Phloem functions to provide food to each part of the plant by the process of transportation.
-The flow of contents is multi-directional and is caused by hydrostatic pressure. Using ATP the companion cells deposit the food and amino acids into sieve tubes. This process increases the osmotic pressure in tubes and the areas that have scarce food will have less osmotic pressure. This will cause food to flow from a high-pressure area to low pressure area.
-The roots using the root pressure absorbs water and minerals from the soil and transports them to the plant with the help of xylem.
-The stomata are pore openings present all over the surface of leaves. Through stomata evaporation takes place. This is called transpiration. The transpiration creates a transpirational pull in leaves causing water to move up in them from the roots through the xylem. The root pressure in roots is not enough to transport water alone thus the transpirational pull adds to its function.

Note: The transport system of plants is the most necessary part of its functioning. Water, minerals, and nutrients required by the plant for its growth are all provided by these tissues only. Xylem, phloem, roots, and stomata, all act in a unified manner to nourish the plant and help in its growth.