[Biology Class Notes] on Difference between Food Chain and Food Web Pdf

The food chain is a sequential pathway that shows that the flow of energy moves or transfers from one organism to the other. In this pathway, energy is not created, nor can it be destroyed but it flows from one level to the other level through different organisms. Similarly, there are producers, consumers, and decomposers who are interconnected through many food chains that create a food web. This shows the interactions between different organisms in an ecosystem. Both the food chain and food web represent the flow of energy and matter in trophic levels and efficiency of energy transfer. In these pathways, organisms are dependent on each other for food.

 

Difference Between Food Chain and Food Web

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Food Chain and its Levels

A Food chain is basically a linear network of connections in a food web starting from producer organisms or an order of events in an ecosystem where one living organism eats another organism.

This consists of trophic levels which have four major parts as follows:

• Sun – It is considered as the major source of food for making food, growth, and development.

• Producers – These include green plants, and it is the first stage in a food chain.

• Consumers – These are those organisms that eat different organisms. This is considered to be the largest part of the food web in the ecosystem.

• Decomposers – These are those organisms that get energy from dead or waste organic material.

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Types of the Food Chain

There are two types of the food chain which are as follows:

1. Detritus Food Chain – This food chain includes different kinds of species of organisms and plants like algae, bacteria, fungi, protozoa, mites, insects, worms, and so on. This food chain begins with dead organic material. The consumed energy passes into composers and detritivores which are eaten by smaller organisms like carnivores.

2. Grazing Food Chain – This food chain starts with green plants and passes through herbivores and then to carnivores. In this food chain, the lowest trophic level acquires energy from photosynthesis

Examples of Food Chain

The term “food chain” refers to a series of events in an ecosystem in which one organism eats another and is subsequently eaten by another. Here is a selection of food chain examples for you to explore:

Food Chains on Land

• Nectar (flowers) → butterflies → small birds → foxes

• Dandelions → snail → frog → bird → fox

• Rice → rat → owl

• Leaves → giraffes → lions → jackals

• Leaves → caterpillars → birds → snakes

• Grass→ antelope → tiger → vulture

Food Chains in Water

• Crayfish → catfish → humans

• Insect → fish → humans

• Caterpillars → turtles → alligators → humans

• Seaweed → periwinkle → ragwor
  m → curlew

• Mayflies → trout → humans

• Phytoplankton → copepod → bluefish → swordfish → human

Chemosynthetic Food Chains

• Bacteria → clams → octopus

• Bacteria → copepods → shrimp → zoarcid fish

• Tubeworms → crabs → shrimp → zoarcid fish

• Microbes → shrimp → crabs

• Mussels → shrimp → anemone

 

Brief on Food web

A food web is a complex interconnected diagram that depicts the overall food interactions among creatures in a given environment. This comprises a number of several interconnected food chains that form a food web. This is usually similar to a food chain, but it is comparatively larger than a food chain. In this, a single organism is consumed by several organisms. Organisms are organised in a food web according to their trophic level. The trophic level of an organism is determined by how it feeds and how it fits into the larger food web.

 

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Applications of the Food Web

• The species interaction can be described very clearly.

• A major set of illustrations regarding the interactions can be made between all the types of species.

• This can be used to study the top to bottom and bottom to top control of community structure.

• This reveals the flow of energy transfer from one level to the other or in terrestrial and aquatic ecosystems.

Importance of Food web

Food webs are useful in understanding that plants are the basis of all ecosystems and food chains, providing nutrients and oxygen required for existence and reproduction. Food webs describe how energy flows across an ecosystem, from the sun to producers to consumers. Other elements can travel through an ecosystem in the same way that energy does. 

When toxic elements or poisons are introduced into an environment, the consequences can be disastrous. Food webs facilitate knowledge of natural selection by depicting species classification, with carnivorous, omnivorous, and tertiary animals at the top of all food chains. Food webs also explain how food scarcity caused by overhunting, poaching, global warming, and habitat destruction disturb populations, eventually leading to extinction.

Examples of Food Web

Desert

• Producers: Cacti, bushes, acacias, flowers, brush

• Primary Consumers: Insects, lizards, rodents

• Secondary Consumers: Tarantulas, scorpions, lizards, snakes

Forest

• Producers: Plants, fruits, nuts, seeds, flowers

• Primary Consumers: Deer, squirrels, frogs, birds, Pikas

• Secondary Consumers: Pine Marten, jackrabbits, ravens, ringtails 

Marine

• Producers and Decomposers: Seagrass, seaweed, algae, plankton, bacteria

• Primary Consumers: Turtles, damselfish, crab, shrimp

• Secondary Consumers: Octopuses, triggerfish, squid, krill

Conclusion

Learning different aspects of the food chain and food web in the early age can really help in the long term.