Match Column I with Column II:
| Column I | Column II |
| A. Natural ecosystem | 1. Producer |
| B. Decomposer | 2. Consumer |
| C. Primary productivity | 3. Forest |
| D. Secondary productivity | 4. Bacteria |
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → A-3, B-4, C-1, D-2
(A) Natural ecosystem — this matches (3) Forest. Forest, grassland and desert are natural terrestrial ecosystems; crop fields and an aquarium are man-made ones.
(B) Decomposer — this matches (4) Bacteria. Decomposers break detritus into inorganic substances. Bacterial and fungal enzymes do this in the step called catabolism.
(C) Primary productivity — this matches (1) Producer. It is the rate of making organic matter by plants during photosynthesis, and plants are the producers.
(D) Secondary productivity — this matches (2) Consumer. It is the rate at which consumers form new organic matter.
NCERT Extract:
Ecosystem–Structure and Function – “… Forest, grassland and desert are some examples of terrestrial ecosystems; pond, lake, wetland, river and estuary are some examples of aquatic ecosystems. Crop fields and an aquarium may also be considered as man-made ecosystems.”
Productivity – “… Primary production is defined as the amount of biomass or organic matter produced per unit area over a time period by plants during photosynthesis. … Secondary productivity is defined as the rate of formation of new organic matter by consumers.”
Decomposition – “… Bacterial and fungal enzymes degrade detritus into simpler inorganic substances. This process is called as catabolism.”