Every question from this NCERT chapter, with a detailed explanation.
Consider the following statements regarding non-biodegradable substances: 1. Some non-biodegradable substances may be inert yet persistent. 2. All non-biodegradable substances actively harm every member of the ecosystem. 3. Non-biodegradable substances are rapidly metabolized by all ecosystem members. Which of the statements given above is/are correct?
Consider the following statements regarding ecosystem dynamics: 1. Producers make solar energy available to the rest of the ecosystem. 2. There is no loss of energy across trophic levels. 3. Human activities influence the environment. Which of the statements given above are correct?
Consider the following statements about enzymes and decomposition: 1. Enzymes in living systems act non-specifically on all substrates. 2. Specificity explains why certain materials are not broken down in the environment. 3. Enzyme specificity ensures that only compatible substrates are broken down. Which of the statements given above are correct?
In a grazing food chain, which group occupies the first trophic level?
Consider the following statements regarding producers in an ecosystem: 1. They convert solar energy into chemical energy. 2. Only green plants act as producers. 3. Some bacteria can be producers. Which of the statements given above is/are correct?
Match List I with List II and select the correct answer using the code given below: List I | List II A. Producers | 1. Herbivores B. Primary consumers | 2. Top/Larger carnivores C. Secondary consumers | 3. Small carnivores D. Tertiary consumers | 4. Autotrophs fixing solar energy
Consider the following statements about the flow of energy in an ecosystem: 1. The flow of energy across trophic levels is reversible. 2. The available energy decreases at successive trophic levels. 3. The energy fixed by autotrophs does not return to the solar input. Which of the statements given above are correct?
Consider the following pairs: Ecosystem type - Example 1. Natural - Pond 2. Natural - Garden 3. Human-made - Crop-field 4. Human-made - Forest Which of the pairs given above are correctly matched?
Consider the following pairs regarding ecosystem types: 1. Natural - Pond 2. Natural - Garden 3. Human-made - Estuary 4. Human-made - Aquarium Which of the pairs given above are correctly matched?
With reference to consumers in an ecosystem, consider the following statements: 1. Herbivores rely directly on producers. 2. Carnivores belong only to the second trophic level. 3. Omnivores feed exclusively on plant matter. Which of the statements given above is/are correct?
Which of the following statements regarding ozone is/are correct? 1. It is a molecule made of three oxygen atoms. 2. At ground level, it is universally beneficial to all organisms. 3. In the upper atmosphere, it performs a protective function against ultraviolet radiation. Select the correct answer using the code given below:
Consider the following statements about biodegradable substances: 1. They are resistant to breakdown by biological processes. 2. Enzymes involved in breakdown are specific in their action. 3. Their breakdown products can re-enter ecological cycles. Which of the statements given above are correct?
Assertion (A): Producers constitute the trophic level with generally the greatest number of individuals in an ecosystem. Reason (R): They are the only level that does not transfer energy to any other level.
Consider the following pairs regarding ecological processes: Process | Characteristic 1. Energy flow | Unidirectional 2. Matter accumulation | Progressive across levels 3. Solar energy capture | Reversible to solar input 4. Trophic energy availability | Increasing at higher levels Which of the pairs given above are correctly matched?
Which one of the following describes the formation of ozone in the upper atmosphere?
Match List I with List II and select the correct answer using the code given below: List I | List II A. Ozone depletion | 1. Avoid mass scaling of soil-intensive alternatives B. Pesticide residues in food | 2. Reducing intake through curbing sources and use C. Non-biodegradable waste | 3. Freezing/Phasing out production of ODS D. Top-soil loss | 4. Avoiding materials not broken down by decomposers
Consider the following statements: 1. Some photosynthetic bacteria are producers. 2. Producers form the second trophic level. 3. Parasites are never classified as consumers in an ecosystem. Which of the statements given above is/are correct?
Consider the following statements regarding ecosystems: 1. Aquariums typically require periodic cleaning by humans to sustain life. 2. An aquarium is a self-sustaining ecosystem requiring no human intervention. 3. Gardens are categorized as human-made ecosystems. Which of the statements given above are correct?
Consider the following statements regarding atmospheric gases: 1. Ozone is harmful and non-essential at higher atmospheric levels. 2. Oxygen (O2) is essential for aerobic life. 3. Ozone performs a protective function in the stratosphere. Which of the statements given above are correct?
Which of the following represents a biotic component of an ecosystem?
Which group of organisms constitutes the second trophic level in a standard food chain?
What percentage of energy is approximately transferred from one trophic level to the subsequent level?
Which term correctly describes the direction of energy flow through an ecosystem?
In a terrestrial ecosystem, which trophic level typically contains the largest number of individuals?
The ozone layer in the stratosphere plays a crucial role in absorbing which type of harmful radiation?
The formation of stratospheric ozone is initiated by the photodissociation of which molecule?