Loading PDF...
Chapter Analysis
Intermediate10 pages • EnglishQuick Summary
The chapter 'Our Environment' discusses the interdependence of various components within an ecosystem, the flow of energy in food chains and webs, and the impact of human activities on the environment. It highlights environmental issues such as ozone layer depletion and waste management, emphasizing the importance of managing both biodegradable and non-biodegradable waste. The chapter also delves into biological magnification and the ways harmful chemicals accumulate in higher trophic levels, ultimately affecting human health.
Key Topics
- •Ecosystem components
- •Food chains and food webs
- •Energy flow in ecosystems
- •Ozone layer depletion
- •Biological magnification
- •Waste management
- •Biodegradable and non-biodegradable substances
- •Impact of human activities on the environment
Learning Objectives
- ✓Understand the interdependence of ecosystem components
- ✓Explain the concept of food chains and webs
- ✓Analyze the unidirectional flow of energy in ecosystems
- ✓Evaluate the impact of human activities on environmental health
- ✓Identify methods to reduce and manage waste
- ✓Understand the significance of ozone layer protection
Questions in Chapter
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
Answer: Example: Plant → Goat → Lion. Trophic levels are the hierarchical levels in an ecosystem, comprising producers at the first level, followed by herbivores, small carnivores, and larger carnivores at higher levels.
Page 211
What is the role of decomposers in the ecosystem?
Page 215
Which of the following groups contain only biodegradable items?
Page 217
What will happen if we kill all the organisms in one trophic level?
Page 217
Additional Practice Questions
What are the main components of an ecosystem?
easyAnswer: An ecosystem comprises biotic components, like plants and animals, and abiotic components, such as soil, water, and air. These components interact to maintain a balance of life, supporting processes such as nutrient cycles and energy flows.
Explain biological magnification and its impact on ecosystems.
mediumAnswer: Biological magnification refers to the increasing concentration of harmful substances, like pesticides, as they move up the trophic levels in a food chain. This results in the highest toxin levels in top predators, affecting their health and disrupting ecosystem balance.
Describe the process of energy flow in an ecosystem.
mediumAnswer: Energy enters an ecosystem through producers who convert sunlight into chemical energy. This energy is transferred to consumers and decomposers through feeding relationships, with significant energy loss at each trophic level, often resulting in a pyramid shape.
Why is managing waste important for environmental health?
hardAnswer: Proper waste management prevents pollution, reduces the impact on wildlife, conserves resources through recycling, mitigates health hazards, and helps in combating issues such as climate change by reducing greenhouse gas emissions.
How does the depletion of the ozone layer affect the environment?
hardAnswer: The depletion of the ozone layer allows more harmful UV radiation to reach the Earth's surface, leading to health problems like skin cancer, damaging ecosystems, and affecting biodiversity by altering habitats and food sources.
NCERT Exemplar
AvailablePractice with NCERT Exemplar problems and solutions for this chapter. Exemplar problems are designed to help you master the concepts with advanced-level questions.
View Exemplar