The main components of the transport system in human beings are the heart,blood, andblood vessels. Heart pumps oxygenatedbloodthroughout the body. It receives deoxygenatedbloodfrom the various body parts and sends this impurebloodto thelungsfor oxygenation.

Why is it necessary to separate oxygenated and deoxygenatedblood inmammals and birds? Ans.�It isnecessaryinmammals and birdstoseparate oxygenatedand de-oxygenatedblood because this makes their circulatory system is more efficient and helps in maintaining constant body temperature.

In highly organized plants, vascular tissues (Xylem and Phloem) are the main components of transportation system. In general, xylem carries thewaterandmineralsfrom roots to the aerialpartsof the plants, whereas phloem carries food from leaves to otherpartsof the plants.

Plantsmusttransport waterfrom the roots to the leaves where it is needed for the process of photosynthesis. Nutrients produced in the leaves by photosynthesis aretransportedto all the parts of theplant. The phloem carries nutrients up and down theplant. Thexylemonly carrieswaterup theplant.

Phloem transportsfoodmaterials from the leaves to different parts of theplant. Thetransportationoffoodin phloem is achieved by utilizing energy from ATP which helps in creating osmotic pressure thattransport foodfrom the area of high concentration to low concentration

main components are heart, blood and blood vessels. The heart pumps oxygenated blood throughout the body and receives de- oxygenated blood then sends it to the lungs for oxygenation. Blood helps in the transport of oxygen, nutrients, CO2, and nitrogenous wastes. Blood vessels, arteries, and veins carry blood to all parts of the body.

2. It is necessary to separate oxygenated and de - oxygenated in mammals and birds because it makes the circulatory system more efficient and helps in maintaining constant body temperature.