Which of the following statements are correct?
(A) A lion eating a deer and a sparrow feeding on grains are ecologically similar consumers.
(B) Predator star fish Pisaster helps in maintaining the species diversity of some invertebrates.
(C) Predators ultimately lead to the extinction of prey species.
(D) Production of chemicals such as nicotine and strychnine by the plants are metabolic disorders.
Choose the correct answer from the options given below.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (A) and (B) only
(A) A lion eating a deer and a sparrow feeding on grains are ecologically similar consumers. — Correct. Both eat another living organism for food. In a broad ecological sense, an animal eating seeds is a predator just as a lion is; NCERT calls herbivores the predators of plants.
(B) Predator star fish Pisaster helps in maintaining the species diversity of some invertebrates. — Correct. When all the starfish were removed from an area, more than 10 species of invertebrates died out within a year, because competition among them was no longer kept down.
(C) Predators ultimately lead to the extinction of prey species. — Incorrect. Predators are usually ‘prudent’. They keep prey numbers under control rather than wiping them out; over-exploiting prey would leave the predator itself without food.
(D) Production of chemicals such as nicotine and strychnine by the plants are metabolic disorders. — Incorrect. Plants make these chemicals as defences against grazers and browsers.