CBSE Important Questions for Class 10 Science Chapter 15 PDF Download

CBSE Important Questions for Class 10 Science Chapter 15: To prepare effectively for Chapter 15 Our Environment students should practice a variety of important questions.

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CBSE Important Questions for Class 10 Science Chapter 15 PDF

CBSE Important Questions for Class 10 Science Chapter 15 PDF

CBSE Important Questions for Class 10 Science Chapter 15 Our Environment

Question 1. Why is the maximum concentration of pesticides found in human beings?

Question 2. Give one method to reduce our intake of pesticides through food.

Question 3. What do the various steps in a food chain represent?

Question 4. What is an ecosystem?

Question 5. Why is a lake considered a natural ecosystem?

Question 6. In the following food chain, if plants provide 500 J of energy to rats, how much energy will be available to hawks from snakes?

Question 7. In the following food chain, if 100 J of energy is available to the lion, how much energy was available to the producers?

Question 8. List two biotic components of a biosphere.

1. Producers: These are organisms like green plants that create their own food.
2. Consumers: These are animals that cannot make their own food and rely on consuming other organisms.

Question 9. Why are green plants called producers?

Question 10. In a food chain of frog, grass, insect, and snake, assign a trophic level to the frog.

Question 11. Why do producers always occupy the first trophic level in every food chain?

Question 12.  What does the term environment mean?

Question 13. Which of the following are always at the second trophic level of food chains? Carnivores, Autotrophs, Herbivores?

Question 14. Which organisms in the food chain will have the highest concentration of non-biodegradable chemicals, and what is this phenomenon called?

Question 15. In a food chain, if 10,000 joules of energy is available to the producer, how much energy will be available to the secondary consumer to transfer it to the tertiary consumer?

• Energy available to the primary consumer (herbivore) = 10% of 10,000 J = 1,000 J.
• Energy available to the secondary consumer (carnivore) = 10% of 1,000 J = 100 J.Hence, 100 J of energy will be available to the secondary consumer to transfer it to the tertiary consumer.

Question 16. If 10,000 J of solar energy is available to the grass, how much energy would be available to the deer to transfer it to the lion?

• Energy available to the deer (primary consumer) = 10% of 10,000 J = 1,000 J.Thus, 1,000 J of energy would be available to the deer to transfer it to the lion.

Question 15. Choose the incorrect statement from the following:

• (a) Ozone is a molecule formed by three atoms of oxygen.
• (b) Ozone shields the surface of the earth from ultraviolet radiations.
• (c) Ozone is deadly poisonous.
• (d) Ozone gets decomposed by UV radiations. (2020)

Question 16 : Write one negative effect on the environment of the affluent lifestyle of a few persons of society. (AI 2016, 2014)

Question 17: Why is the excessive use of CFCs a cause of concern? (Foreign 2016)

Benefits of Practicing CBSE Important Questions for Class 10 Science Chapter 15

• Reinforcement of Knowledge : Revising important questions helps reinforce fundamental concepts related to ecosystems, food chains, and environmental science.
• Clarification of Doubts : Working through these questions can clarify misunderstandings and solidify knowledge.

• Application of Knowledge : Students learn to apply theoretical knowledge to practical situations, which enhances critical thinking and problem-solving skills.
• Diverse Question Formats : Various types of questions prepares students to tackle different problem formats in exams.

1. Familiarity with Exam Format : Practicing important questions familiarizes students with the exam format, reducing anxiety on exam day.
2. Time Management : Regular practice helps students manage their time effectively during exams.

• Targeted Revision : Students can identify topics where they struggle, allowing them to focus their revision efforts accordingly.
• Enhanced Focus on Concepts : This targeted approach helps ensure a comprehensive understanding of all concepts.

• Better Grades : Regular practice can lead to improved performance in assessments, contributing to better overall grades.
• Conceptual Clarity : A strong grasp of the chapter’s concepts can lead to higher marks in both formative and summative assessments.