CBSE Class 9 Answered

Living organisms continuously need materials produced in one area to be brought to another area in order to carry out their essential life activities. This requires a transport system to be present, which can transport the materials from one place to another within the living body.

Let us understand this in detail.

All plants need water. The wilted leaves recover when water is added to the soil, which means that water has been conducted upward into the leaves. Also, all the parts of the plant need water. Likewise, the food produced in the leaves has to be transported to other parts of the plant including the stem, the roots flowers and fruits etc. All this transportation is the function ofconducting tissues. Similarly, in animals, the food absorbed by the gut has to be carried to all the body parts, oxygen absorbed in the lungs has to be transported to every cell of the body, the carbon dioxide produced in the cells has to be carried to the lungs for elimination, and the poisonous body wastes like urea has to be transported to the kidneys for elimination in urine, and so on. All such functions are the outcome of a transportsystem.