Notes of nutrition of plants

Those organisms which can make food themselves from simple substances like carbon dioxide and water by the process of photosynthesis are called autotrophs. All green plants are autotrophs.

The plants which do not contain chlorophyll in them cannot carry out photosynthesis and depend for food on other organisms. They are divided into two main groups:

1. Parasites: The plant which lives on or inside another organism and derives the food from it is called as parasite. These plants produce certain special type of roots called as sucking roots which penetrate into the host plant for e.g. Cuscuta plant.
2. Insectivorous Plants: Those green plants which obtain their food partly from insects are called insectivorous plants. These plants have specialized leaves to catch the insects. They are also called as carnivorous plants. For e.g. Pitcher plant, Sundew plant, venus fly-trap plant etc.
3. Saprotrophs: Those non-green plants which obtain food from dead or decaying organic matter are called saprotrophs. The saprophytic plants secrete digestive juices on the dead and decaying organic matter and convert it into a solution. They absorb the nutrients from this solution. For e.g. fungi such as mushrooms, bread mould and yeast.
4. The living together of two different species of plants as if they are parts of the same plant and help each other in obtaining food is called symbiosis and such plants are known as symbiotic plants like lichens.