Read the passage and answer the following questions:
The earthworm is often referred to as the farmer's 'friend' due to its beneficial role in the breakdown of complex organic matter and soil aeration. Similarly, decomposers play a crucial role in converting complex organic matter into inorganic substances like carbon dioxide, water, and nutrients through the process of decomposition. Detritus, consisting of dead plant remains (leaves, bark, flowers) and animal waste, serves as the raw material for decomposition. Decomposition involves several important steps: fragmentation, leaching, catabolism, humification, and mineralisation. Detritivores, like earthworms, contribute to the process by breaking down detritus into smaller particles, which is known as fragmentation. Through leaching, water-soluble inorganic nutrients percolate into the soil horizon and precipitate as less accessible salts. Bacterial and fungal enzymes play a vital role in degrading detritus into simpler inorganic substances, and this process is referred to as catabolism. It's essential to understand that all these steps in decomposition occur simultaneously on the detritus. Humification and mineralisation are significant processes occurring during decomposition in the soil. Humification involves the transformation of organic matter into stable, dark-coloured substances like humus. Mineralisation, on the other hand, refers to the conversion of organic nutrients into inorganic forms that plants can readily absorb.
Which of the following is a raw material for decomposition?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → All of these
The passage states that “Detritus, consisting of dead plant remains (leaves, bark, flowers) and animal waste, serves as the raw material for decomposition”.
So dead plants, dead leaves and the dead remains of animals are all part of detritus, and all of them are broken down by decomposers.
Option (1) Dead plants — Correct statement, but it is only one of the correct points, so on its own it is not the answer. Dead plant remains are part of detritus.
Option (2) Dead remains of animals. — Correct statement, but it is only one of the correct points, so on its own it is not the answer. Dead remains of animals, including fecal matter, are part of detritus.
Option (3) Dead remains of leaves. — Correct statement, but it is only one of the correct points, so on its own it is not the answer. Fallen leaves are one of the dead plant remains named in the passage.