- The leaves have a green pigment called chlorophyll. It helps leaves to capture the energy of the sunlight.
- Besides leaves, photosynthesis also takes place in green stems and green branches. Desert plants have green stems which carry out photosynthesis.
- Algae are nitrogenous substance which contains nitrogen.
A plant like cascuta (amarbell) does not havechlorophyll. It takes readymade food from the plant on which it is climbing. The plant on which it climbs is called a host. Since it deprives the host of valuable nutrients. It is called a parasite.
- Insectivorous plants:- these are insect eating plants. The insects is digested by the digestive juices secreted in the pitcher, the pitcher like structure is the modified part of the leaf.
Fungi have a different mode of nutrition. They secrete digestive juices on the dead conert it into a solution. Then they absorb the nutrient from it. This mode is called saprotrophic nutrition. Plants which use saprotrophic mode of nutrition are called saprotrophs. Eg: A mushroom as a saprotrophs.
Some organisms live together and share shelter and nutrients. This is called symbiotic relationship. Organismlike algae and fungus live together. The fungus provides shelter. Water and minerals to the algae and in return the algae provides food which is prepared by photosynthesis.
Rhizobium cannot make its own food. So it lives in the roots of gram, peas, moong beans and other legumes and provides them nitrogen in return , the plants provide food and shelter to the bacteria, they have a symbiotic relationship.