Match List-I with List-II.
| List-I (Example) | List-II (Interaction) |
|---|---|
| A. Barnacles growing on the back of a whale | I. Predation |
| B. Human liver fluke with a snail and a fish as intermediate hosts | II. Parasitism |
| C. A sparrow eating seeds | III. Commensalism |
| D. Plants offering juicy and nutritious fruits to the animals that disperse their seeds | IV. Mutualism |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → A-III, B-II, C-I, D-IV
(A) Barnacles growing on the back of a whale — this matches (III) Commensalism. The barnacles benefit, while the whale neither gains nor loses.
(B) Human liver fluke with a snail and a fish as intermediate hosts — this matches (II) Parasitism. The fluke is a trematode parasite that lives inside its human host and harms it; it needs two intermediate hosts to complete its life cycle.
(C) A sparrow eating seeds — this matches (I) Predation. In a broad sense an animal eating a plant is a predator, and the book says a sparrow eating any seed is no less a predator.
(D) Plants offering juicy and nutritious fruits to the animals that disperse their seeds — this matches (IV) Mutualism. The animal gets food and the plant gets its seeds spread, so both benefit.
NCERT Extract:
Population Interactions – “… When we think of predator and prey, most probably it is the tiger and the deer that readily come to our mind, but a sparrow eating any seed is no less a predator.”
Population Interactions – “… The human liver fluke (a trematode parasite) depends on two intermediate hosts (a snail and a fish) to complete its life cycle.”
Population Interactions – “… (iv) Commensalism: This is the interaction in which one species benefits and the other is neither harmed nor benefited. An orchid growing as an epiphyte on a mango branch, and barnacles growing on the back of a whale benefit while neither the mango tree nor the whale derives any apparent benefit.”
Population Interactions – “… Plants offer rewards or fees in the form of pollen and nectar for pollinators and juicy and nutritious fruits for seed dispersers.”