Food Chain and Food Web explain the transfer of energy and nutrients between organisms in an ecosystem. Understanding trophic levels, producers, consumers and decomposers is essential for Ecology and Environment preparation.
Correct Answer:
(D)
Primary as well as a secondary consumer
In food chain there are trophic levels i.e., Autotroph, Primary consumer, Secondary consumer and Tertiary consumer. The primary consumer is the herbivores (that feed on the plant), the secondary consumer is small carnivores (feeding on primary consumer) and the tertiary consumer is larger carnivores. So, in food chain, man is the primary as well as a secondary consumer who feeds on both plant, products and meat.
Ques: 2
Concerning food chains in ecosystems, consider the following statements
A food chain illustrates the order in which a chain of organisms feeds upon each other.
Food chains are found within the population of a species.
A food chain illustrates the number of organism, which is eaten by others.
Which of the statements given above is /are correct?
Correct Answer:
(A) Only 1
Now most obvious aspect of nature is that energy must pass from one living organism to another. When herbivorous animals feed on plants, energy is transferred from plants to animals. In an ecosystem, some of the animals feed on other living organisms while some feed on dead organic matter. The latter form the detritus food chain. Each chain usually has only four to five such links. Food chains are not found within the population of a species. Because this would mean a human being eating another human being (human beings are single species)
Note: The correct order of a common marine food chain is –
Diatom → Crustaceans → Herrings
Ques: 3
The correct order in the food chain of the various components of a terrestrial grass ecosystem is –
Correct Answer:
(A) Grass, Grasshopper, Frog, Snake
Any substance consumed to provide nutritional support for an organism is called food. Plants are self-feeding and make for their own food whereas animals depend on plants for food. Food chain depicts the flow of energy through different organisms in an ecosystem. Notably, this flow is unidirectional. The correct order of different components in the above food chain is as follows:
Grass → Grasshopper → Frog → Snake
↓ ↓ ↓ ↓
(Producer) (Primary Consumer) (Secondary Consumer) (Tertiary Consumer)
Ques: 4
Which one of the following organisms is likely to show the highest concentration of DDT, once it has been introduced into the ecosystem?
Correct Answer:
(C) Snake
DDT is a non-biodegradable, biomagnifying pollutant which increases in concentration from producers, primary consumers, secondary consumers to tertiary consumers. In the question, only the snake represents the tertiary consumers, so the concentration of DDT will be highest in the snake.
Ques: 5
Consider the following statements regarding Food Web:
1. Here an organism of higher level trophic feeds on a specific organism of lower trophic level.
2. Food web has a role in improving the adaptability and competitiveness of an organism.
Which of the statements given above is/are correct?
Correct Answer:
(B) 2 only
In Food web is a multitude of networks showing the flow of energy. Here an organism of a higher trophic level has access to more members of a lower trophic level. It has a role in improving the adaptability and competitiveness of an organism.
In Food chain, an organism of higher level trophic feeds on a specific organism of lower trophic level.
Ques: 6
Which of the following best describes the flow of energy in a food web?
Correct Answer:
(A) a) From producers to consumers, then to decomposers.
In a food web, energy flows from producers to consumers, and then ultimately to decomposers. Producers, like plants, capture energy from the sun through photosynthesis and convert it into chemical energy, which is then transferred to consumers when they eat the plants. These consumers, which can be herbivores, carnivores, or omnivores, obtain energy by consuming other organisms. Finally, when organisms die, decomposers, like bacteria and fungi, break down the organic matter and release nutrients back into the environment, completing the cycle.