Practice free Ecosystem (Botany) NEET multiple-choice questions online with instant answers and detailed explanations. No login required.
Which of the following processes in decomposition is primarily responsible for the conversion of detritus into simpler inorganic substances by bacterial and fungal enzymes?
According to the NCERT text, 'Bacterial and fungal enzymes degrade detritus into simpler inorganic substances. This process is called as catabolism.'
Detritus refers to the raw material for decomposition. Which of the following components would NOT be considered part of detritus?
The NCERT states, 'Dead plant remains such as leaves, bark, flowers and dead remains of animals, including fecal matter, constitute detritus'. Living phytoplankton are producers, not dead remains.
Humus, formed during decomposition, possesses several characteristics. Which of the following is an incorrect statement regarding humus?
The NCERT explicitly states that humus 'undergoes decomposition at an extremely slow rate', making option 3 incorrect.
The process of mineralisation in decomposition involves:
The NCERT defines mineralisation as 'the humus is further degraded by some microbes and release of inorganic nutrients occur by the process known as mineralisation'.
Which of the following factors would generally lead to a faster rate of decomposition?
According to the NCERT, 'Warm and moist environment favour decomposition whereas low temperature and anaerobiosis inhibit decomposition'. Also, 'decomposition rate is slower if detritus is rich in lignin and chitin'.
Earthworms are considered 'farmer's friends' because they contribute significantly to decomposition by:
The NCERT mentions, 'You may have heard of the earthworm being referred to as the farmer’s ‘friend’. This is so because they help in the breakdown of complex organic matter as well as in loosening of the soil.' This corresponds to fragmentation.
Decomposition is a crucial ecological process. Which statement best summarizes its overall outcome?
The NCERT clearly states, 'decomposers break down complex organic matter into inorganic substances like carbon dioxide, water and nutrients and the process is called decomposition.'
In the process of leaching, water-soluble inorganic nutrients move into the soil horizon and get precipitated as unavailable salts. This step primarily prevents:
Leaching causes nutrients to 'get precipitated as unavailable salts', meaning they are not immediately available for uptake. While eventually they might become available, this step renders them temporarily inaccessible.
Which of the following is NOT an important step in the process of decomposition?
The NCERT lists 'fragmentation, leaching, catabolism, humification and mineralisation' as important steps in decomposition. Photosynthesis is a process of primary production, not decomposition.
The rate of decomposition is significantly influenced by the chemical composition of detritus. Which of these combinations would lead to the slowest decomposition rate?
The NCERT states, 'decomposition rate is slower if detritus is rich in lignin and chitin, and quicker, if detritus is rich in nitrogen and water-soluble substances like sugars.'
Ready to ace NEET?
Free access · No credit card required
Yes. You can attempt every Ecosystem question on this page for free without logging in, and check the correct answer with a detailed explanation instantly.
No account is required to attempt questions and view answers. A free account adds bookmarks, personal notes, and progress tracking.
The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.