Food Chain:
• Anything which we eat to live is called food.
• Food contains energy.
• Food can be transferred from one organism to the other.
• The process of transfer of food (energy) from one organism to a series of organisms is called as “food chain”.
A food chain is a picture (or) model that shows the flow of energy from autotrophs (producers) to series of organisms in an environment, as shown in the following figure. Infact, all the food chains starts with the sun. The sun provides energy for plants. The producers (plants) can make their food themselves with the help of the sunlight, chlorophyll, water and air. The consumers, including animals and humans, cannot make their own food. They are always depending upon the producers for their energy. Decomposers are the micro-organisms that break down the dead animals and plants and release nutrients that become part of the soil, which are re-used by new plants, back to the starting point of the food chain.
Types of food chain:
Three basic types of food chains are found in a typical eco system. They are:
1. Grazing food chains.
2. Detritus food chains.
3. Parasitic food chains.
1.Grazing food chains: Grazing food chain starts with green plants (producers) and goes to decomposer food chain (or) detritus food chain through herbivores and carnivores.
It has two types : a. Terrestrial food chain and b. Aquatic food chain
a.Terrestrial food chain: Food chain on land is called terrestrial food chain.
Example: Grassland food chain , Forest land food chain , Desert land food chain
Grass land food chain Grasses Grasshoppers Frog Snake Eagles
Forest food chain Green plants Deer Tiger (or) lion
b.Aquatic food chain : This food chain is slightly different from terrestrial food chain. It is seen in aquatic (water) eco system. Food chain in water is called “Aquatic food chain”. Example: Marine food chain Example: Ocean Fresh water food chain Example: Pond, lake, streams, etc.
Food chain in a pond Phytoplankton Zoo Plankton Small fish Large fish Man
Marine Food chain: Sea Weeds Small fish Large fish Sharks and other animals
2.Detritus’ food chain: Detritus food chain starts with dead organic matter (plants and animals) and goes to decomposer through consumers. Detritus food chains, independent of solar energy, but they depend on influx of dead organic matter.
Example: Dead Plants Soil mitts Algae Crabs Small fish Large fish
3.Parasitic food chain: Parasitic food chain operates in many ecosystems. In this food In this food chain either consumer (or) producer is parasitized and the food passes to smaller organisms. A parasitic food chain involves host parasite hyper parasites’ links.
Example : Trees Fruit eating birds Lice & Bugs Bacteria Fungi
