Food-Chain-featured

Food Chain, Food Web and Energy Flow in Food Chain

Ecosystem Components

The main processes happening in an environment include feeding and the circulation of chemical elements, together with the energy flowing through the ecosystem.

Food-Chain-featured

An ecosystem is made up of three main components, the producers, the consumers, and the decomposers. All are concerned with the feeding processes, the flow of chemical elements, and the flow of energy.

Producers

Producers are the autotrophs green photosynthetic plants, which capture and bring light energy into the ecosystem. They are able to produce organic food from simple inorganic compounds. They are autotrophic organisms.

Example: Algae, Cyanobacteria, Plants

Consumers

Consumers are all the organisms, mainly animals, which obtain energy directly or indirectly from the producers as ready-made organic food. They are generally heterotrophic organisms.

Example: Humans

Decomposers

Decomposers are primarily the fungi and bacteria, which get their energy from the dead and decaying plants and animals. They release chemical elements as ions. The primary chemical ions are nitrates, ammonia, phosphates, potassium, and calcium.

Food Chain

The transfer of food energy from the source in plants through a series of organisms with repeated stages of eating and being eaten is called the food chain.

OR

The process of eating and being eaten in the ecosystem in the form of a linear chain is called as food chain.

Basically, all animals depend on plants for their food. Eagle may consume bluebird, but bluebird consumes pests like caterpillar and caterpillar feeds on the yard or green leaves. This is an example of a basic food cycle.

Grass or Green leaves –> Caterpillar or Insect –> Small Birds –> Eagles –> Dogs

Food Web

The interlocking pattern of food chains is called a food web.

The Food web is actually “the combination of lots of food chains”. Food webs are not actually as simple as explained because a lot of animals eat more than one type of food at different times as fox does not feed completely on bunny however also takes beetles, rats, etc. All the food chains and food webs begin with a green plant (producer) and may consist of 3 to five links or trophic levels.

Food-Web

Trophic Levels in Food Web

In a food web, more complex trophic levels or food links are as follow

T1-Level:  In the food chain, T1 is the first trophic producer level, Includes all green plants, grass, and phytoplankton.

T2-Level:  Second trophic level T2 to consist of the primary consumer-like beetle rat and rabbit which eat plants but eaten by T3.

T3-level:  Third trophic level T3 are secondary consumer-like fox, owl which eat T2.

T4-level:  Fourth trophic level T4 is consists of tertiary consumers.

Significance of Food Web
Maintain the stability of the environment

The range of pathways in a food web helps to maintain the stability of the ecosystem. For example, owls prey on rabbits and mice. If a disease reduces the rabbit population; fewer plants are taken in. The larger plant population produces more fruits and seeds, which, in turn, support a bigger mouse population. The increased number of mice ends up being the major food source for the owls.

The rabbit population slowly increases, and these primary consumers once again become a food source for the owls. Thus, nature maintains a balance.

Predation and its Significance

Predation: The association between two animals in which one kills the other to get nutrition or the interaction between predator and prey is called predation.

Predator: An animal which captures and readily kills live animals for its food is called a predator.

Prey: The animal that is caught/killed and eaten by the predator is called prey.

Significance of Predation

The sizes of populations of predator and prey relate to each other. The size of each population is figured out by the size of the other. If the number of prey is big, this results in a boost in the number of predators; as a predator feeds on the prey; the number of prey starts to fall. The number of predators likewise reduces, because they have a smaller food supply. As the number of predators decreases, the number of prey begins to increase. This food relationship of predator-prey develops a “cycle”.

Further Reading:  Cheek Teeth in Mammals

Examples: cat/mouse, fox/rabbit, seal/fish, frog/mosquito, hawk/small birds, and so on.

Predation-significance

Grazing and its significance

Grazing: The mode of feeding in which the animals consume grasses is called grazing.

Grazers: The animals that feed on grass and herbs are called grazers.

Numerous animals like rabbits, goats, sheep, cows, buffaloes, and horses feed on grasses. These animals live in pastureland where they feed upon grass, herbs, and shrubs.

Grazers

Impacts of Grazing on Ecosystem
Over Grazing

If a lot of animals are kept on pasture, they eat the grass they eat the grasses down to the root though grasses are more resistant than herbaceous plants and have the ability to regrow very fast, the hooves of grazing animals trample the soil into a hard layer as a result of which rainwater will not penetrate this soil. It runs off from the upper surface removing the fertile topsoil with it.

The final result of overgrazing is totally barren land. It runs off from the upper surface area eliminating the fertile topsoil with it.

Moderate grazing

Grazing is a very important factor in determining the ecosystem. Moderate grazing is extremely useful to keep the meadow ecosystem. It destroys the rivals and assists the grass to grow well. Overgrazing might result in the transformation of a meadow or grassland into a desert.

The Flow of Energy in the Food Chain of an Ecosystem

The energy in the form of radiant heat and light from the sun lows through an ecosystem passing through the different trophic levels (links) and radiates again back into outer space.

Gross Primary Production: The total amount of energy fixed by plants is gross primary production.

Net Primary Production:   The amount of energy left after plants have met their respiratory needs is net primary production, which shows up as plant biomass.

About 1% of the total energy from the sun is trapped by the producers in an ecosystem. The remaining 99% of solar energy is used to evaporate water, heat up the soil, and is then lost to outer space. As energy is transferred from one trophic level to the next, from producer to primary consumer, between 80 to 90% of last as the original energy is heat as a by-product of respiration. However, a continuous lux of energy from the sun prevents the ecosystem from running down. A pyramid of energy can be constructed showing energy transfer in a community of organisms.

heat-energy

A short food chain of two or three links supports a community more efficiently than a long chain of five links where much of the original energy from the producers would ever reach those organisms at higher trophic levels. Decomposers are able to obtain energy by converting plant and animal tissues and waste into inorganic mineral ions.

FAQs: Food Chain, Food Web, and Energy Flow in Ecosystems

1. What are the main components of an ecosystem?

  • An ecosystem comprises producers, consumers, and decomposers, each contributing to feeding processes, chemical element circulation, and energy flow.

2. Who are the producers in an ecosystem?

  • Producers are autotrophs, primarily green photosynthetic plants like algae, cyanobacteria, and plants, capable of converting light energy into organic food.

3. Who are the consumers in an ecosystem?

  • Consumers are organisms, mainly animals, obtaining energy directly or indirectly from producers by consuming ready-made organic food. Humans are examples of consumers.

4. What role do decomposers play in an ecosystem?

  • Decomposers, such as fungi and bacteria, derive energy from dead and decaying plants and animals, releasing essential chemical elements like nitrates, ammonia, phosphates, potassium, and calcium.

5. What is a food chain?

  • A food chain is the sequential transfer of food energy through a series of organisms, starting with plants and progressing through various stages of consumption and predation.

6. How does a food web differ from a food chain?

  • A food web is an interlocking pattern of multiple food chains, representing a more complex network of feeding relationships in an ecosystem.

7. What are trophic levels in a food web?

  • Trophic levels in a food web include T1 (producers), T2 (primary consumers), T3 (secondary consumers), and T4 (tertiary consumers), indicating different stages in the flow of energy.

8. Why is a food web significant in maintaining the stability of the environment?

  • A food web’s complexity helps maintain ecosystem stability by creating diverse pathways. For example, if a disease reduces rabbit populations, it influences plant consumption, impacting mouse and owl populations, creating a natural balance.

9. What is predation, and why is it significant in ecosystems?

  • Predation is the interaction where one animal kills another for nutrition. The predator-prey relationship regulates population sizes, creating dynamic cycles that impact both predator and prey populations.

10. What is grazing, and how does it affect ecosystems?

  • Grazing is the feeding mode where animals consume grass. Overgrazing can lead to soil erosion and barren land, while moderate grazing helps maintain meadow ecosystems by controlling competitors.
Further Reading:  Fruit Morphology and Types of Fruits

11. How does energy flow through the food chain of an ecosystem?

  • Energy in the form of sunlight is captured by producers, passed through trophic levels, and radiates back into space. Gross primary production represents total energy fixed by plants, while net primary production is the energy remaining after meeting plant respiratory needs.

12. What percentage of solar energy is trapped by producers in an ecosystem?

  • About 1% of solar energy is captured by producers, while the remaining 99% is utilized for various purposes, including evaporating water and heating the soil, before being lost to outer space.

13. How efficient is energy transfer between trophic levels in a food chain?

  • Between 80 to 90% of energy is lost as heat in each transfer between trophic levels. Short food chains with fewer links tend to support ecosystems more efficiently than longer chains.

14. How do decomposers contribute to the energy flow in ecosystems?

  • Decomposers obtain energy by converting plant and animal tissues into inorganic mineral ions, facilitating the recycling of nutrients in the ecosystem.

 

Take the 19 MCQs to test your knowledge

  1. What are the three main components of an ecosystem?
    • a) Producers, Consumers, Decomposers
    • b) Plants, Animals, Rocks
    • c) Sun, Water, Air
    • d) Carnivores, Herbivores, Omnivores

    Answer: a) Producers, Consumers, Decomposers

  2. Which of the following is an example of a producer?
    • a) Lion
    • b) Mushroom
    • c) Human
    • d) Snake

    Answer: b) Mushroom

  3. What is the primary function of decomposers in an ecosystem?
    • a) Produce organic food
    • b) Capture sunlight
    • c) Release chemical elements from dead organisms
    • d) Hunt for prey

    Answer: c) Release chemical elements from dead organisms

  4. What is the transfer of food energy from plants through a series of organisms known as?
    • a) Food Pyramid
    • b) Food Chain
    • c) Food Cycle
    • d) Food Web

    Answer: b) Food Chain

  5. In a basic food cycle, what is the primary source of energy for Eagles?
    • a) Small Birds
    • b) Caterpillar
    • c) Green leaves
    • d) Grass

    Answer: a) Small Birds

  6. What is the interlocking pattern of food chains in an ecosystem called?
    • a) Food Circle
    • b) Trophic Levels
    • c) Food Web
    • d) Energy Chain

    Answer: c) Food Web

  7. Which trophic level includes secondary consumers in a food web?
    • a) T1-Level
    • b) T2-Level
    • c) T3-Level
    • d) T4-Level

    Answer: c) T3-Level

  8. How does a food web contribute to maintaining the stability of the environment?
    • a) By causing imbalance
    • b) By reducing the number of predators
    • c) By creating diverse pathways
    • d) By eliminating decomposers

    Answer: c) By creating diverse pathways

  9. What is predation in an ecosystem?
    • a) The interaction between predators
    • b) The process of plants capturing sunlight
    • c) The interaction between two animals where one kills the other for nutrition
    • d) The decomposition of organic matter

    Answer: c) The interaction between two animals where one kills the other for nutrition

  10. What is the primary significance of predation in an ecosystem?
  • a) Maintaining balance in predator and prey populations
  • b) Decreasing the number of predators
  • c) Increasing the number of prey
  • d) Eliminating herbivores

Answer: a) Maintaining balance in predator and prey populations

  1. What is grazing in an ecosystem?
  • a) The mode of feeding in which animals consume grasses
  • b) The process of hunting for prey
  • c) The interaction between producers and decomposers
  • d) The decomposition of dead animals

Answer: a) The mode of feeding in which animals consume grasses

  1. Which animals are known as grazers?
  • a) Predators
  • b) Herbivores
  • c) Omnivores
  • d) Decomposers

Answer: b) Herbivores

  1. What is the impact of overgrazing on an ecosystem?
  • a) Increased fertility of the soil
  • b) Desertification
  • c) Enhanced plant growth
  • d) Preservation of biodiversity

Answer: b) Desertification

  1. What is the primary function of moderate grazing in a meadow ecosystem?
  • a) Decreasing plant growth
  • b) Transforming grassland into a desert
  • c) Maintaining ecosystem balance
  • d) Increasing soil erosion

Answer: c) Maintaining ecosystem balance

  1. What is the total amount of energy fixed by plants known as?
  • a) Net Primary Production
  • b) Gross Primary Production
  • c) Energy Pyramid
  • d) Food Energy

Answer: b) Gross Primary Production

  1. What percentage of the total solar energy is trapped by producers in an ecosystem?
  • a) 50%
  • b) 75%
  • c) 1%
  • d) 99%

Answer: c) 1%

  1. What is the term for the amount of energy left after plants have met their respiratory needs?
  • a) Gross Primary Production
  • b) Net Primary Production
  • c) Energy Transfer
  • d) Photosynthetic Energy

Answer: b) Net Primary Production

  1. In a community of organisms, what is lost as a by-product of respiration during energy transfer?
  • a) Sunlight
  • b) Water
  • c) Oxygen
  • d) Heat

Answer: d) Heat

  1. How does a short food chain support a community more efficiently than a long chain?
  • a) By reducing biodiversity
  • b) By conserving energy
  • c) By eliminating producers
  • d) By increasing the number of trophic levels
Further Reading:  Flight in Birds: Evolution, Morphology, Muscular System with MCQs

Answer: b) By conserving energy

 

Summary

The tutorial on the Food Chain, Food Web, and Energy Flow in an Ecosystem covers various essential components and interactions within ecological systems. Here’s a brief summary of the key concepts:

  1. Ecosystem Components:
    • The ecosystem comprises producers (autotrophs), consumers (heterotrophs), and decomposers.
    • These components are involved in feeding processes, the flow of chemical elements, and energy circulation.
  2. Producers, Consumers, Decomposers:
    • Producers, such as green plants, capture light energy for photosynthesis.
    • Consumers, like animals, derive energy from producers as ready-made organic food.
    • Decomposers, including fungi and bacteria, release chemical elements by decomposing dead plants and animals.
  3. Food Chain:
    • The transfer of food energy through a linear sequence of eating and being eaten, involving multiple organisms, constitutes a food chain.
    • Example: Grass → Caterpillar → Small Birds → Eagles → Dogs.
  4. Food Web:
    • An interlocking pattern of food chains forms a food web.
    • It involves various animals eating different foods at different times, contributing to a complex ecological structure.
  5. Trophic Levels in Food Web:
    • Trophic levels include producers (T1), primary consumers (T2), secondary consumers (T3), and tertiary consumers (T4) in a food web.
  6. Significance of Food Web:
    • Maintains ecosystem stability by creating diverse pathways.
    • Balances populations; for instance, owls prey on mice, helping control the mouse population.
  7. Predation:
    • The act of one animal killing another for nutrition.
    • Predators, like foxes, interact with prey, leading to a dynamic cycle in population sizes.
  8. Grazing:
    • Grazers, such as rabbits and cows, feed on grass and herbs in pasturelands.
    • Overgrazing can lead to desertification, while moderate grazing helps maintain the meadow ecosystem.
  9. Impacts of Grazing on Ecosystem:
    • Overgrazing results in barren land and soil erosion.
    • Moderate grazing is crucial for ecosystem balance, promoting healthy grass growth.
  10. Energy Flow in the Food Chain:
    • Energy from the sun flows through trophic levels in an ecosystem.
    • Gross Primary Production represents total energy fixed by plants, while Net Primary Production is the energy left after meeting plant respiratory needs.
  11. Pyramid of Energy:
    • About 1% of solar energy is trapped by producers; the rest is lost during energy transfer.
    • A pyramid of energy demonstrates the efficiency of short food chains in supporting communities.
  12. Decomposers:
    • Decomposers play a vital role by converting plant and animal tissues into inorganic mineral ions, closing the loop in the ecosystem.

Understanding these concepts provides insights into the intricate balance and dynamics of ecosystems, emphasizing the importance of diverse interactions and energy flow for ecological sustainability.