GUIDED BY: DR. K PRIYAN, CIVIL & STRUCTURAL ENGG DEPT. PRESENTED BY: SHREYANSH JETHWA ( ) PARTH TRIVEDI ( ) TEJAS PATEL ( ) G H PATEL COLLEGE OF ENGG. & TECH.(011), VALLBH VIDYANAGAR BRANCH: ELECTRICAL

THE FOOD CHAIN & FOOD WEB

THE FOOD CHAIN

W HAT IS A F OOD C HAIN ? A food chain is the path by which energy passes from one living thing to another.

A food chain shows how each living thing gets its food. Some animals eat plants and some animals eat other animals. Each link in this chain is food for the next link. A food chain always starts with plant life and ends with an animal.

All food begins with the sun. seeds plants animals

EACH FOOD CHAIN HAS THREE MAIN TROPHIC LEVELS  PRODUCER  CONSUMER  DECOMPOSER

P RODUCERS Producers make their own food Green plants use energy from the sun to make food Producers are on the bottom of the food chain

C ONSUMERS Consumers hunt, gather, and store food because they cannot make their own.

There are three types of consumers: Animals that eat only plants.. Animals that eat only animals.. Animals that eat both plants and animals…

T HREE T YPES OF C ONSUMERS Herbivores Carnivores Omnivores

H ERBIVORES Animals who eat plants such as: grasshoppers rabbits squirrels deer pandas

C ARNIVORES Animals who only eat other animals such as: tigers lions hawks wolves cougars

O MNIVORES Animals who eat both plants and animals such as: humans bears

F UNGI AND BACTERIA PLAY AN IMPORTANT ROLE IN NATURE. T HEY BREAK DOWN THE UNUSED DEAD MATERIAL AND TURN THEM INTO NUTRIENTS IN THE SOIL, WHICH PLANTS USE TO GROW. T HEY ARE AN IMPORTANT PART OF THE FOOD CHAIN.

Simple food chain could start with 1, which is eaten by rabbits. Then the rabbits are eaten by foxes.

B IGGER F OOD C HAINS Here's another food chain, with a few more animals. It starts with acorns, which are eaten by mice. The mice are eaten by snakes, and then finally the snakes are eaten by hawks. At each link in the chain, energy is being transferred from one animal to another.

TYPES OF FOOD CHAIN  GRAZING FOOD CHAIN  PARASITIC FOOD CHAIN  DETRITUS FOOD CHAIN

GRAZING FOOD CHAIN SUCH TYPE OF FOOD CHAIN STARTS FROM PRODUCER AND ENDS WITH HIGHER CONSUMER LEVEL. IN EVERY TROPHIC LEVEL THE SIZE OF ORGANISM INCREASES WHILE THEIR NUMBER DECREASES

PARASITIC FOOD CHAIN  THIS TYPE OF FOOD CHAIN STARTS FROM BIG HOSTS AND ENDS WITH THE PARASITIC ORGANISMS.

DETRITUS FOOD CHAIN  THIS TYPE OF FOOD CHAIN STARTS FROM DEAD ORGANISMS AND ENDS WITH DECOMPOSERS SUCH AS BACTERIA.  IT IS HOWEVER LESS EFFICIENT AS MEJOR PORTION OF ENERGY IS LOST TO THE ENVIRONMENT WITHOUT BEING USED PROPERLY.

EXAMPLE

P YRAMID OF N UMBERS Carnivore populations are smaller in comparison to the rest of the ecosystem. They require more food to sustain their lives than the lower organisms. The amount of useable energy that is transferred from trophic level to trophic level only 10%.

W HAT IS A F OOD W EB ? A more realistic way of looking at the relationship of plants and animals in an environment Several food chains linked together A predator from one food chain may be linked to the prey of another food chain

A food web is a network of many food chains.

O VERLAPPING FOOD CHAINS ARE CALLED FOOD WEBS.

M ARINE F OOD W EBS

M ARINE F OOD W EB

F OREST /R AINFOREST W EBS

 How energy is transferred in an ecosystem.

start with a food chain.

show all the connections between living things in an ecosystem.

mean that secondary consumers eat different things too.

show all the connections between living things in an ecosystem.