Ecosystem
58 CBSE Class 12 Biology past-year questions from 4 papers, 2023 to 2026, with answers and worked solutions.
- Difficulty: 31 easy · 27 moderate.
- Most-asked subtopics: Ecological Pyramids (20), Energy Flow (13), Productivity (11).
- Updated 8 October 2026.
#1Ecosystem: Structure and Function
#2Ecosystem: Structure and Function
Below is shown a pond that represents a self-sustaining natural ecosystem with both biotic and abiotic components interacting in a balanced food web. Based on the diagram, answer the questions :#3Ecosystem: Structure and Function
Below is shown a pond that represents a self-sustaining natural ecosystem with both biotic and abiotic components interacting in a balanced food web. Based on the diagram, answer the questions :#4Ecosystem: Structure and Function
#5Productivity
Done a few? Here’s your next move
#6Productivity
For Questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.#7Productivity
#8Productivity
#9Productivity
#10Productivity
#11Productivity
#12Productivity
#13Productivity
#14Productivity
#15Productivity
#16Decomposition
For Questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.#17Decomposition
#18Decomposition
#19Decomposition
Question Nos. 13 to 16 consists of two statements Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below :#20Decomposition
#21Decomposition
#22Decomposition
Question Nos. 13 to 16 consists of two statements, Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below :#23Decomposition
#24Decomposition
#25Decomposition
#26Energy Flow
#27Energy Flow
#28Energy Flow
#29Energy Flow
#30Energy Flow
#31Energy Flow
#32Energy Flow
For Questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.#33Energy Flow
#34Energy Flow
#35Energy Flow
#36Energy Flow
Below is shown a pond that represents a self-sustaining natural ecosystem with both biotic and abiotic components interacting in a balanced food web. Based on the diagram, answer the questions :#37Energy Flow
Below is shown a pond that represents a self-sustaining natural ecosystem with both biotic and abiotic components interacting in a balanced food web. Based on the diagram, answer the questions :#38Energy Flow
For Questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) given below :#39Ecological Pyramids
#40Ecological Pyramids
#41Ecological Pyramids
#42Ecological Pyramids
#43Ecological Pyramids
#44Ecological Pyramids
#45Ecological Pyramids
#46Ecological Pyramids
For Questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.#47Ecological Pyramids
#48Ecological Pyramids
#49Ecological Pyramids
#50Ecological Pyramids
Showing the first 50 of 58.
See all 58 questionsMore chapters in this subject
- Biodiversity and Conservation86
- Biotechnology and its Applications112
- Biotechnology: Principles and Processes158
- Evolution93
- Human Health and Disease185
- Human Reproduction119
- Microbes in Human Welfare105
- Molecular Basis of Inheritance165
- Organisms and Populations87
- Principles of Inheritance and Variation167
- Reproductive Health62
- Sexual Reproduction in Flowering Plants119