Read the following passage carefully and answer the given questions.
The earthworm is referred to as the farmer's friend. This is because they help in the breakdown of complex organic matter as well as in loosening of soil. Similarly, decomposers break down complex organic matter into inorganic substances like carbon dioxide, water and nutrients and the process is called decomposition. Dead plant remains such as leaves, bark, flowers and dead remains of animals, including fecal matter, constitute detritus, which is the raw material for decomposition. Some of the steps in the process of decomposition are fragmentation, catabolism, leaching, humification etc.
The degradation of detritus into simpler inorganic substances by the bacterial and fungal enzymes is called as-
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Catabolism
Option (1) Mineralization — Incorrect. Mineralisation is the last step of decomposition. Some microbes break down humus further, and inorganic nutrients are released. It acts on humus, not on fresh detritus.
Option (2) Leaching — Incorrect. Leaching is a physical process. Water carries the soluble nutrients down into the soil, where they settle as salts. No enzyme is involved.
Option (3) Fragmentation — Incorrect. Fragmentation is done by detritivores such as earthworms, not by bacteria and fungi. It only breaks detritus into smaller pieces. The pieces are still organic matter.
Option (4) Catabolism — Correct. Catabolism means breaking down large molecules into smaller ones. In decomposition, the enzymes of bacteria and fungi do this to detritus.
Note: This passage is taken from NCERT as it is. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
NCERT Extract:
Decomposition – …
