Food is synthesized in the green parts of the leaf and is transported to all parts of the plant. For this plant has specialized organs called Phloem tissue. It has two components companion cells and sieve tubes.
We all know plant need water and mineral for their growth. For this we irrigate plant and put manure to it. How these elments gets absorbed by the plant? For this there are two theories.
There are two types of transport systems in higher plant
a. Water and mineral transport which consist Xylem,root and stomata.
b. Food transport system which consist Phloem and companion cells.
Why is it necessary to separate oxygenated and deoxygenated blood in mammals and birds