Decomposition in ecosystem - class-XI
Description: decomposition in ecosystem | |
Number of Questions: 72 | |
Created by: Arav Srivastava | |
Tags: ecosystems ecosystem ecology and environment zoology botany biology |
During the process of decomposition.
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$CO _2$ is consumed and $O _2$ is released
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$O _2$ is consumed and $CO _2$ is released
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$CO _2$ is consumed and $H _2O$ is released
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None of these
Decomposition is the process that concerns breakdown of complex organic matter by decomposers to inorganic raw materials like carbon dioxide, water and various nutrients. Oxygen is required by aerobic bacteria for decomposition.
Decomposers are also called as.
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Transducers
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Reducers
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Micro-consumers
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Both (b) and (c)
Decomposers are also called as reducers because they are able to remove or degrade the dead bodies of organisms and due to their small size they are known as microconsumers.
Given is a table of factors affecting microbial decomposition. ($'+'$ means 'favouring' and $'-'$ means inhibiting or lowering). Select the correct option.
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High temperature- $+$, Lack of oxygen- $+$, Moist environment- $+$, Lignin and chitin in detritus- $-$
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High temperature- $+$, Lack of oxygen- $-$, Moist environment- $+$, Lignin and chitin in detritus- $-$
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High temperature- $-$, Lack of oxygen- $-$, Moist environment- $+$, Lignin and chitin in detritus- $-$
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High temperature- $-$, Lack of oxygen- $+$, Moist environment- $+$, Lignin and chitin in detritus- $-$
Decomposition is a type of ______
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aerobic respiration
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anaerobic respiration
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exothermic reaction
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none of these.
When organic materials decompose in the presence of oxygen, the process is called “aerobic.” The aerobic process is most common in nature. For example, it takes place on ground surfaces such as the forest floor, where droppings from trees and animals are converted into relatively stable humus. There is no accompanying bad smell when there is adequate oxygen present. In aerobic decomposition, living organisms, which use oxygen, feed upon the organic matter. They use the nitrogen, phosphorus, some of the carbon, and other required nutrients. Much of the carbon serves as a source of energy for the organisms and is burned up and respired as carbon dioxide. Since carbon serves both as a source of energy and as an element in the cell protoplasm, much more carbon than nitrogen is needed. Generally, about two-thirds of carbon is respired as $C0 _2$, while the other third is combined with nitrogen in the living cells. However, if the excess of carbon over nitrogen (C: N ratio) inorganic materials being decomposed is too great, biological activity diminishes. Several cycles of organisms are then required to burn most of the carbon.
The rotting dead matter in the soil is called
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Weathering
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Humus
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Soil profile
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Top soil
_____________ carry out decomposition process.
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Microorganisms
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Animals
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Both A and B
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Decomposers
Decomposers are organisms that break down dead or decaying organisms, and in doing so they carry out the natural process of decomposition.
.......... play a very important role in decomposition of organic matter in the soil
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Cat
-
Plants
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Microorganisms
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All of the above
Micro-organisms dwell in soil. They contribute to various processes related to the soil, plants and atmosphere. One of the processes is decomposition of dead remains of plants and animals
The rate of decomposition of hydrogen peroxide can be slowed down through
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Glycerin
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Manganese oxide
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Vanadium oxide
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Platinum
Glycerin
Glycerin affects the rate of decomposition of hydrogen peroxide and slows down the reaction.
Which of these help in decomposition of organic wastes?
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Bacteria
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Fungi
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Earthworm
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All of the above
When organic wastes such as leftover food, plant and animals waste is collected in heaps, decomposers such as bacteria, insects such as earthworms and fungi act on it and break it down. This product which is formed by this action of decomposers is called compost. This process is called composting and the compost can be used to increase the plant yield. Thus the correct answer is option D.
Which of the following gases is/are produced by decomposers during the decaying process?
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Only carbon dioxide gas
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Only carbon dioxide and nitrogen gases
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Only oxygen gas
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Only carbon dioxide and oxygen gases
Decomposers feed on the dead or decaying organic matter(carbohydrate, proteins and lipids ) and produce nitrogen and carbon dioxide gases as an organic matter are mainly made up of carbon, oxygen, hydrogen and nitrogen. Thus, the correct answer is option B.
The release of inorganic nutrients from the biomass is called as
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Production
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Respiration
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Decomposition
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None of the above
The release of inorganic nutrient from the degradation of organic matter is called as
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Fragmentation
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Humification
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Mineralisation
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Leaching
During the process of decomposition in which stage complex organic matter convert into inorganic ions and salts by fungi?
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Mineralisation
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Catabolism
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Fragmentation
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All of these
Mineralisation is a process in which complex organic matter present in humus is converted into inorganic salts and ions. It is done by the action of saprophytic fungi.
Which of the following process helps in nutrient conservation?
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Mineralisation
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Immobilisation
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Leaching
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Nitrification
Immobilization is the conversion of inorganic compounds to organic compounds by microorganisms or plants, by which it is prevented from being accessible to plants. Immobilization is the opposite of mineralization. Plants utilize minerals in inorganic form. Hence, immobilization helps in nutrient conservation.
The decomposed organic matter is called
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Callose
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Callus
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Litter
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Humus
Decomposition is the process of breaking of complex organic matter into simpler inorganic matter. There are five steps of decomposition. These are fragmentation, leaching, catabolism, humification and mineralization. Fragmentation is the process of breaking of detritus into small pieces by detrivores. Leaching is the process of releasing nutrients in the water and seeping into the soil. Catabolism is the process of breaking down of complex molecules into the simpler molecules. Humification is the process of formation of dark colored humus on the soil. The decomposed organic matter is called as humus. Mineralization is the process of degradation of the hummus to release inorganic nutrients.
Breakdown of detritus into smaller particles by earthworm is a process called
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Humification
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Fragmentation
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Mineralisation
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Catabolism
Decomposition is the process of breaking of complex organic matter into simpler inorganic matter. There are five steps of decomposition. These are fragmentation, leaching, catabolism, humification and mineralization. Fragmentation is the process of breaking of detritus into small pieces by earthworm. Leaching is the process of releasing nutrients in the water and seeping into the soil. Catabolism is the process of breaking down of complex molecules into the simpler molecules. Humification is the process of formation of dark colored humus on the soil. MIneralization is the process of degradation of the hummus to release inorganic nutrients.
Breakdown of detritus into small particles by detrivores is called
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Leaching
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Humification
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Catabolism
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Mineralisation
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Fragmentation
Decomposition is the process of breaking of complex organic matter into simpler inorganic matter. There are five steps of decomposition. These are fragmentation, leaching, catabolism, humification and mineralization. Fragmentation is the process of breaking of detritus into small pieces by detrivores. Leaching is the process of releasing nutrients in the water and seeping into the soil. Catabolism is the process of breaking down of complex molecules into the simpler molecules. Humification is the process of formation of dark colored humus on the soil. MIneralization is the process of degradation of the hummus to release inorganic nutrients.
The process of breakdown of detritus by detrivores is
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Mineralisation
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Fragmentation
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Leaching
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Humification
Decomposition is the process of breaking of complex organic matter into simpler inorganic matter. There are five steps of decomposition. These are fragmentation, leaching, catabolism, humification and mineralization. Fragmentation is the process of breaking of detritus into small pieces by detrivores such as earthworm. Leaching is the process of releasing nutrients in the water and seeping into the soil. Catabolism is the process of breaking down of complex molecules into the simpler molecules. Humification is the process of formation of dark colored substance humus on the soil. It undergoes microbial action at a slow rate. Mineralization is the process of degradation of the hummus to release inorganic nutrients.
During the process of decomposition, in which stage complex organic matter is converted to inorganic ions and salts by fungi?
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Mineralization
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Catabolism
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Fragmentation
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All of the above
Mineralization in the process of decomposition in which complex organic matter is oxidized into soluble inorganic ions and salts. It increases bioavailability of the nutrients as soluble inorganic form is readily available to plants. The process is carried out by soil microorganisms like bacteria and fungi.
The different steps involved in the process of decomposition of detritus are
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Fragmentation
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Leaching and Catabolism
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Humification and mineralization
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All of the above
The ability to produce organic compound in unit time is
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Leaching
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Productivity
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Poaching
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Conductivity
- Productivity is the rate of production of new biomass by an individual, population.
- Productivity is a key source of economic growth and competitiveness.
- A country's ability to improve its standard of living depends almost entirely on its ability to raise its output per worker, i.e., producing more goods and services for a given number of hours of work.
- Hence, The ability to produce the organic compound in unit time is Productivity.
- So, the correct answer is 'Productivity'.
If breakdown of the detritus by detritivores is called fragmentation, then degradation of the detritus into simple inorganic substances,by bacterial and fungal enzymes is known as
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Leaching
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Humifiacation
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Catabolism
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Mineralization
If the breakdown of the detritus by detrivores is called fragmentation, then the degradation of the detritus into simple inorganic substances, by bacterial and fungal enzymes is known as catabolism.
Rate of decomposition is controlled by:
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Chemical composition id detritus
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Food web
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Climatic factor
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More than one is correct
A large number of organic compounds can be decomposed by:
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Photoeterotorphs
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Pseudomonas
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Photolithotrophs
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Chemoheterotrophs
During the process of decomposition in which stage complex organic matter convert into inorganic ions and salts by fungi?
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Mineralization
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Catabolism
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Fragmentation
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All of the above
Decomposition is a type of ______.
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Aerobic respiration
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Anaerobic respiration
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Exothermal reaction
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None of these
In which treatment, microorganism decompose fine organic matter?
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Preliminary Treatment
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Biological Treatment
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Secondary Treatment
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Tertiary Treatment
Bacteria which carry out decomposition of organic matter is known as
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Anaerobic Bacteria
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Aerobic Bacteria
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Virus
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Rotifers
End product of 'aerobic' decomposition are:
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Unstable
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stable
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reactive
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Non Combustible
What is 'PH' of rainwater?
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5.7
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9
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4
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3
Breakdown of organic matter is known as:
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Decomposition
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Condensation
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Precipitation
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Infiltration
Lowest 'pH' measurement observed in kane and Pennsylvania, was approximately
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2.9
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4
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3
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2.7
Bacterial decomposition of organic matter, releases $NO _{2}$ into
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Stratosphere
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Troposphere
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Atmosphere
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Biosphere
Obnoxious ordours also pollute air due to decomposition of ____________.
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Garbage
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Rubbish
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Air pollution
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Organic solid waste
Which bacteria can flourish and carry out decomposition of organic matter, both in presence and absence of oxygen?
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Facultative Bacteria
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Aerobic Bacteria
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Anaerobic Bacteria
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Blue green algae
'Aerobic' decomposition takes place in
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Two stages
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Three stages
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Four Stages
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Five stages
In first stage of aerobic decomposition, carbonaceous matter is being
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Reduced
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Oxidized
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Formed
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Decomposed
The plant parts when fully decomposed by microorganism and mixed in the soil is caIled as
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Litter
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Duff
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Humus
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All of the above
Humus is a dark-brown or black organic substance made up of decayed plant or animal matter which are fully decomposed by microorganisms like bacteria. Humus provides nutrients for plants and increases the ability of soil to retain water. It has a characteristic black or dark brown color and is organic due to an accumulation of organic carbon.
Humus is
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Dead and decayed organic matter
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Living matter
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Fertilizers
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Living animal, plants and microbes
Humus is dark, organic material that forms in soil when plant and animal matter decays. When plants drop leaves, twigs, and other material to the ground, it piles up. This material is called leaf litter. When animals die, their remains add to the litter. The thick brown or black substance that remains after most of the organic litter has decomposed is called as humus. Humus contains many useful nutrients for healthy soil.
The slow rate of decomposition of fallen Iogs in nature is due to their
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Anaerobic environment around them
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Low cellulose content
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Low moisture content
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Poor nitrogen content
Photosynthetically fixed carbon is eventually degraded by micro-organisms and two major forms of carbon known as methane and carbon dioxide. The micro-organisms breakdown the complex compounds of dead protoplasm of producers compounds of dead protoplasm of producers and consumers absorb some of the decomposition products and release simple substances. The slow rate of decomposition of fallen logs in nature is because of low moisture content.
What does the term 'NPK' mean?
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Nitrate, potash and calcium
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Nitrogen, phosphate and chromium
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Nitrogen, phosphorus and potassium
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Nitrate, protein and vitamins.
Nitrogen(N). phosphorous(P), potassium (K) are used to label fertilizers based on the relative content of these chemicals.
Humus is an example of
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Soil structure
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Cryustalloids
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Organic colloids
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None of these
- Humus particles are tiny pieces of organic matter and are known as Organic Colloids.
- Humus is important because it retains moisture in the soil, loosens the soil permitting better aeration and drainage, and encourages the increase of soil organisms which help make nutrients available to plants.
- Hence Humus is an example of organic colloids.
- So, the correct answer is 'Organic colloids'.
Microorganism act upon a dead plant to produce
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Humus
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Mushroom
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Wood
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Sand
Dead plants and animals are degraded in soil by decomposing bacteria and fungi. The material formed after the decomposition process is called humus. Humus is very rich in nutrients and black in colour. Greater the amount of humus more is the soil productivity. Thus, the correct answer is option A.
Mark the correct statement
a) Microbes helps in decomposition process
b) They help in maintaining biogeochemical cycle
c) Microbes only helps in carbon cycle, they don't have any role in nitrogen cycle
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a, b
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a, c
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b, c
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All
Microbes play important role in our lives and in the environment. They help in the decomposition process and in maintaining the biogeo-chemical cycles like carbon and nitrogen cycles.
Which of the following process is involved in the processing of manures?
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The decomposition of animal excreta
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Plant waste
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Above both options are correct
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None of these
Manure is prepared by the decomposition of animal excreta and plant waste.
What causes the decomposition of organic matter in soil?
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Insects
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Plants
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Algae
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Bacteria
Which of the following statement regarding decomposition is false?
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Warm and moist environment favors decomposition.
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Decomposition rate is slower if detritus is rich in chitin and lignin.
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Earthworm is a detritivore.
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Precipitation of soluble inorganic nutrients into the soil horizon of unavailable salt is called as mineralization.
Decomposition takes part in recycling of biogeochemicals and creating space for newer generations of organisms. A number of processes are involved in decomposition.
In short, mineralisation is the process by which humus is further degraded by some microbes to release inorganic substances.
Passage of minerals from top soil to subsoil through seepage of water is known as
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Leaching
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Percolation
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Conduction
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Transpiration
Downward passage of mineral, from upper soil layer to lower soil strata is called
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Percolation
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Leaching
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Weathering
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Runaway
A liquid when slowly passes through a filter, this is called percolation.
Thus, the correct answer is option (B).
For recycling of materials which one is most necessary ______________.
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producers
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Consumers
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Decomposers
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None of above
The decomposers are heterotrophic organisms that break up the dead bodies of plants and their waste products into smaller bits or molecules. The reducers release molecules to the environment as chemical to be used
Formation of organic matter takes place by
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Chemical weathering
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Soil micro-organisms
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Herbivores
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Soil water
In the absence of decomposers, ecosystem functioning is adversely affected due to
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Blocking of energy flow
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Blocking of mineral cycling
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Blocking of solar energy to herbivores
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Rate of decomposition of other components will increase
Pheretima and its close relatives obtain nourishment from
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Decaying fallen leaves and soil organic matter
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Soil insects
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Small pieces of fresh fallen leaves of Maize and others
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Sugarcane roots
Pheretima is a genus of earthworm. Pheretima and its close relatives obtain nourishment from decaying fallen leaves and soil organic matter. They are called as decomposers. They decomposes the dead organic matter and releases nutrients back into the environment.
Slow rate of decomposition of fallen logs in nature is due to
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Anaerobic environment around them
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Low cellulose contents
-
Low moisture content
-
Poor nitrogen content
The slow rate of decomposition of fallen logs in nature is due to their low moisture content The cellulose is in high amount in fallen logs.
Decomposition rate is slow, if detritus is rich in
-
Nitrogen
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Humus
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Sugars
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Lignin and chitin
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Water soluble substances
Decomposition is the process of breaking down organic matter into simple inorganic matter. Under same environmental conditions, the rate of decomposition various due to change in composition of detritus. If detritus is rich in lignin and chitin, the decomposition rate is slow. If detritus is rich in nitrogen, the decomposition rate is relatively high.
Important steps in decomposition are
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Fragmentation and mineralisation
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Leeching and catabolism
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Humification and mineralisation
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All the above
Decomposition is the process of breaking of complex organic matter into simpler inorganic matter. There are five steps of decomposition. These are fragmentation, leaching, catabolism, humification and mineralization. Fragmentation is the process of breaking of detritus into small pieces by detrivores. Leaching is the process of releasing nutrients in the water and seeping into the soil. Catabolism is the process of breaking down of complex molecules into the simpler molecules. Humification is the process of formation of dark colored humus on the soil. MIneralization is the process of degradation of the hummus to release inorganic nutrients.
Which process of decomposition is correctly described?
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Leaching: Water soluble inorganic nutrients rise to the top layers of soil
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Fragmentation: Carried out by organisms such as earthworm
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Humification: Leads to accumulation of a dark coloured substance humus which undergoes microbial action at a very fast rate
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Catabolism: Last step in decomposition under fully anaerobic conditions
During the process of decomposition in which stage complex organic matter is converted into organic ions and salts by fungi
-
Mineralisation
-
Catabolism
-
Fragmentation
-
All the above
Decomposition is the process of breaking of complex organic matter into simpler inorganic matter. There are five steps of decomposition. These are fragmentation, leaching, catabolism, humification and mineralization. Fragmentation is the process of breaking of detritus into small pieces by detrivores. Leaching is the process of releasing nutrients in the water and seeping into the soil. Catabolism is the process of breaking down of complex organic molecules into the simpler organic ions and salts by fungi. Humification is the process of formation of dark colored humus on the soil. MIneralization is the process of degradation of the hummus to release inorganic nutrients.
Which one of the following processes during decomposition is correctly described ?
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Fragmentation Carried out by organisms such as earthworm
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Humification Leads to the accumulation of a dark coloured substance humus which undergoes microbial action at a very fast rate
-
Catabolism Last step in the decomposition under fully anaerobic condition
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Leaching Water soluble inorganic nutrients rise to the top layers of soil
What is the correct sequence of the microorganisms involved in the decomposition of plant residues in the terrestrial ecosystems?
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Actinomycetes
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Spore producing bacteria
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Mould fungi and no spore producing bacteria
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Cellulose mycobacterium
Choose the correct sequences.
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$CO _{2}$ in atmosphere $\rightarrow $ decomposers $\rightarrow $ organic carbon in animals $\rightarrow $ organic carbon in plants.
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$CO _{2}$ in atmosphere $\rightarrow $ organic carbon in plants $\rightarrow $ organic carbon in animals $\rightarrow $ inorganic carbon in soil.
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Inorganic carbonates in water $\rightarrow $ organic carbon in plants $\rightarrow $ organic carbon in animals $\rightarrow $ scavengers.
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Organic carbon in animals $\rightarrow $ decomposers $\rightarrow CO _{2}$ in atmosphere $\rightarrow $ organic carbon in plants.
Nutrient cycles circulate matter through the biosphere. The nutrients regularly alternate between living (biotic) and nonliving (abiotic) components. Hence the nutrient cycles are also called as biogeochemical cycles. The important nutrient cycles are water cycle, carbon cycle, nitrogen cycle, mineral cycle. In the carbon cycle, atmospheric carbon is fixed into organic compounds like carbohydrates by green plants during the process of photosynthesis. The organic compounds are consumed by heterotrophic organisms like animals. The waste materials of animals and dead bodies of animals and plants are acted upon by detrivorous organisms, releasing the mineral nutrients like carbon, nitrogen, sulphur etc back to the environment.
The slow rate of decomposition of fallen logs is due to
-
poor nitrogen content
-
anaerobic environment
-
low cellulose contents
-
low moisture contents
Low or reduced moisture alters and reduces the decomposition process. A slow rate of composition of fallen logs is likely due to low moisture contents.
Which of the following factors is not limiting?
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CO$ _2$ concentration
-
Light intensity
-
Temperature
-
Oxygen
Which association below is not correct?
-
Cumulus congestus - anvil top
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Cumulus - fair weather cumulus
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Altocumulus castellanus - resemble "little castles"
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Stratus fractus - scud
Which one of the following is a major link in decomposer food chain?
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Anthracoceros
-
Gyps
-
Anser
-
Pavo
Gyps is a genus of vultures characterized by bald head, broad wings and mainly dark plumage. They are large scavenging birds, feeding mostly from carcasses of dead animals and thereby forming an important link in the decomposes food chain.
Thus, the correct answer is (B) Gyps.
In summers, decomposition proceeds faster than in
-
Spring
-
Winter
-
Autumn
-
Hot weather
50% of incident energy is lost due to:
-
Consumers
-
Producers
-
Microorganisms
-
Planktons
Presence of hydrogen sulphide indicates anaerobic
-
Decomposition
-
Eutrophication
-
Degradation
-
Biodegradation
The correct match among the following is
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Producers--- act upon the decomposed substances and transform them into different forms of inorganic and organic substances
-
Consumers--- are autotrophic members of ecosystem
-
Decomposers--- feed upon dead decaying living organisms and break them into simpler compounds fit for use of producers
-
None of the above
The green plant in the ecosystem-terminology are called as producers. All animals depend on plants (directly or indirectly) for their food needs. They are hence, called as consumers and also heterotrophs.
The breakdown of detritus into smaller particles by earthworm is a process called as
-
Humification
-
Fragmentation
-
Mineralisation
-
Catabolism
Steps of decomposition are:
Earthworm is said to decompose detritus substances.
-
True
-
False
-
Ambiguous
-
Data insufficient
Earthworm is an important organism in the process of decomposition. It is said to decompose detritus substances thus said to be a detrivore.
A pollution free stream within a few miles downstream of a point at which a small amount of sewage is being dumped into it. This is the result of
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Succession
-
Eutrophication
-
Evaporation
-
Photosynthesis
-
Decomposition