Symbiosis

Symbiosis

             The condition in which there is a close physical association between individuals of a pair of species is called symbiosis. In this association both the organisms are benefited and no one is harmed. Let us discuss symbiosis in details with illustrations.

Illustration 1

Symbiotic relationship between groundnut and plant rhizobium

     Groundnut, pea, pulses and soyabean belong to the family fabaceae. The root system of these plants contains beads like outgrowth called nodules. A bacterium called rhizobium lives in these root nodules. Rhizobium helps the plants to absorb nitrogen from the atmosphere. In turn, the plants offer nutrients and shelter to rhizobium.

Illustration 2

Symbiotic relationship in Lichens  

        The Lichens are the composite plant. They contain both algae and fungi. The algal component is generally unicellular. The fungal component supplies moisture, shelter and minerals to algae. The algal component prepares food for the fungi. The fungal component of Lichens cannot live, if algal component is removed.

Illustration 3

Symbiotic relationship in Mycorrhiza

              Mycorrhizae are short and forked roots. They are commonly seen in pines, oaks and birches. These roots have no root cap. The outer zone of roots contains fungus. These roots are more efficient in mineral absorption. Thus the plants are benefited by fungus. In turn, the plants offer nutrients and shelter to the fungus.