In plants, transport system is not complicated as in animals. Transport of water and minerals. Plants absorb water and minerals by the roots. The roots have root hair. The root hair increase the surface area of the root for the absorption of water and mineral nutrients dissolved in water. The root hair is in contact with the water present between the soil particles.
Can you guess how water moves from the root to the leaves? What kind of transport system is present in plants? Well, Boojho is right. Plants have pipe-like vessels to transport water and nutrients from the soil. The vessels are made of special cells, forming the vascular tissue. A tissue is a group of cells that perform specialised function in an organism. The vascular tissue for the transport of water and nutrients in the plant is called the xylem. The xylem forms a continuous network of channels that connects roots to the leaves through the stem and branches and thus transports water to the entire plant.
You know that leaves synthesise food. The food has to be transported to all parts of the plant. This is done by the vascular tissue called the phloem. Thus, xylem and phloem transport substances in plants. The transport system in plants consists of bundles of tubes in the stem, branches and roots. These tubes are called xylem and phloem. The main function of xylem is to transport water and dissolved minerals from the roots to rest of the plant body.
Transport of substance in plants:
To circulate water, essential nutrients, excretory products, and gases within the plants for various purposes, transportation in plants is necessary. In vascular tissues, this transportation in the plant takes place. By a suction force, water and minerals are transported to various parts of the plant.
Plants absorb water and minerals by the roots. The roots have root hair. The root hair increase the surface area of the root for the absorption of water and mineral nutrients dissolved in water. The root hair is in contact with the water present between the soil particles.
In plants, there are pipe-like vessels through which water and minerals can enter the plants. These vessels are made up of elongated cells and thick walls. A group of cells forms a tissue that performs a specialized function within the organisms. These are conducting tissues. These conducting tissues are divided into two types which are xylem and phloem.
Xylem: It is a vascular tissue that spreads from the top to bottom of the plant. For the transport of water molecules, it helps a lot. It also plays a vital role in the case of dissolved substances from the root hairs to aerial parts of the plant. It transfers water in one direction. Commonly, xylem occupies the central part of the vascular bundle.
Phloem: It is also vascular tissue. In a plant where the necessity of food molecules is there, the use of the phloem transportation process will take place.
The food manufactured in the leaves is transported to different parts of the plant. This transpiration of food material from leaves to the others parts of plant is carried out by the tissue called phloem and process transport food material is called translocation. The phloem consists of those vessels known as sieve tubes. Xylem and phloem together form the vascular or connective tissue.
Transpiration: Transpiration is a process that involves loss of water vapour through the stomata of plants. Transpiration is thought to be a 'necessary cost or evil' to allow the plant to absorb water from the soil. It is an inevitable process.
Transpiration is important in plants for three major reasons: Cooling of the plant: the loss of water vapour from the plant cools down the plant when the weather is very hot.
The transpirational pull: when the plant loses water through transpiration from the leaves, water and mineral salts from the stem and roots moves, or is `pulled', upwards into the leaves. Water and is therefore taken up from the soil by osmosis and finally exits the plants through the stomata.
Plant structure: young plants or plants without woody stems require water for structural support. Transpiration helps maintain the turgidity in plants.
Conclusion:
Plants absorb mineral nutrients and water from the soil. Not all the water absorbed is utilised by the plant. The water evaporates through the stomata present on the surface of the leaves by the process of transpiration. The evaporation of water from leaves generates a suction pull (the same that you produce when you suck water through a straw) which can pull water to great heights in the tall trees. Transpiration also cools the plant.
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