Nutrition in Plants

• Science (Chap-1)                                     Nutrition in Plants
• Plants can synthesize food  for themselves where the animals including humans can not.
• Humans and animals are directly or indirectly dependent on plants.
• Plants are the only organisms that can prepare food for themselves by using water, carbon dioxide and minerals.
• Nutrition is the mode of taking food by an organism and its utilization by the body.
• The mode of nutrition in which organisms make food themselves from single substances is called Autotrophic (auto-self, trophos -nourishment) nutrition. Example- Plants
• Animals and most other organisms who take food prepared by plants are called Heterotrophs.
• Food making process in plants is known as Photosynthesis.
• Leaves are known as the food factories of plants.
• Carbon dioxide from air is taken in through the tiny pores present on the surface of leaves. Such pores are called Stomata.
• Water and minerals are transported to the leaves by the vessels which run like pipes throughout the root, the stem, the branches and the leaves.
• The leaves have a green pigment called Chlorophyll which helps leaves to capture the energy of the sun light.
• Since the synthesis of food takes place in the presence of sunlight, it is called Photosynthesis(photo means light and synthesis means to combine).
• Chlorophyll, sunlight, Carbon dioxide and water are necessary to carry out the process of photosynthesis
• Carbon dioxide(CO2) + Water(H2O) + Sunlight  ( Carbohydrate + Oxygen
• The desert plants have green stems which carry out photosynthesis.
• Algae are green in colour as it contains Chlorophyll. It can also prepare their own food by photosynthesis.
• Cuscuta plant does not have chlorophyll. It takes readymade food from the plant on which it is climbing. So, it is known as parasite.
• The plant on which Cuscuta plant climbs is called the host.
• The Pitcher plant can trap insects and digest them. Also known as insectivorous(carnivorous) plants.
• The mode of nutrition in which organisms(fungi) take in nutrients fron dead and decaying matter is called Saprotrophic nutrition.
• Organisms with saprotrophic mode of nutrition are called Saprotrophs. Example- Mushrooms
• The bacterium called Rhizobium can make atmospheric nitrogen and convert it into a usable form.
• Rhizobium can not make its own food. So, it often lives in the roots of legumes(gram, dals,peas etc.) and provides the nitrogen. In return, the plants provide food and shelter to the bacteria. 
• The farmers can reduce the use of nitrogenous fertilizer by growing leguminous plants.
• Some organisms live together and share both shelter and nutrients. This relationship is called Symbiosis.
• In organisms called lichens, a chlorophyll containing partner, which is an alga and a fungus live together.