Ecosystem

Which of the following statements about energy flow in an ecosystem is correct?

1. Energy is recycled continuously like nutrients.
2. Energy flows in one direction and is ultimately lost as heat.
3. Energy increases at higher trophic levels.
4. Producers obtain energy from decomposers.

Which of the following environmental factors has the greatest influence on the rate of decomposition?

1. Soil colour only
2. Temperature and moisture
3. Wind velocity only
4. Altitude only

The detritus food chain begins with:

1. Green plants
2. Herbivores
3. Dead organic matter
4. Carnivores

Which of the following ecological pyramids can be both upright and inverted?

1. Pyramid of energy only
2. Pyramid of biomass and pyramid of numbers
3. Pyramid of energy and pyramid of biomass
4. Pyramid of energy only in aquatic ecosystems

In the grazing food chain, the first trophic level is occupied by:

1. Herbivores
2. Carnivores
3. Producers
4. Decomposers

Which of the following organisms are primarily responsible for nutrient recycling in an ecosystem?

1. Producers
2. Consumers
3. Decomposers
4. Parasites

Which of the following correctly represents the relationship between Gross Primary Productivity (GPP) and Net Primary Productivity (NPP)?

1. GPP = NPP − Respiration
2. NPP = GPP − Respiration
3. Respiration = NPP − GPP
4. NPP = GPP + Respiration

The amount of organic matter produced by producers per unit area per unit time is known as:

1. Standing crop
2. Productivity
3. Biomass
4. Detritus

In an aquatic ecosystem, the pyramid of biomass is generally:

1. Always upright
2. Always inverted
3. Sometimes upright and sometimes inverted, depending on the ecosystem
4. Horizontal

Which of the following stages of decomposition involves the formation of a dark-colored, amorphous substance that is highly resistant to microbial action?

1. Fragmentation
2. Leaching
3. Humification
4. Mineralization

Which of the following is considered the ultimate source of energy for nearly all ecosystems?

1. Wind
2. Water
3. Sun
4. Soil

The process by which decomposers convert complex organic matter into simpler inorganic substances is called:

1. Photosynthesis
2. Decomposition
3. Assimilation
4. Respiration

Which ecological pyramid is always upright?

1. Pyramid of numbers
2. Pyramid of biomass
3. Pyramid of energy
4. Pyramid of organisms

According to the 10% law proposed by Lindeman, if producers contain 20,000 J of energy, the energy available to the primary consumers will be approximately:

1. 20 J
2. 200 J
3. 2,000 J
4. 10,000 J

Which of the following correctly represents the direction of energy flow in an ecosystem?

1. Consumers → Producers → Decomposers
2. Producers → Consumers → Decomposers
3. Decomposers → Producers → Consumers
4. Producers → Decomposers → Consumers

Which of the following ecologists has tried to put price-tags on nature's life support services?

1. Robert May
2. David Tilman
3. Robert Constanza
4. Paul Ehrlich

Global GNP is about:

1. 33 trillion US $
2. 18 trillion US $
3. 12 trillion US $
4. 22 trillion US $

Robert Constanza and his colleague put price tag on nature's life support services. On which service of ecosystem they put maximum percent of this annual average.

1. Nutrient cycling
2. Climate regulation
3. Recreation
4. Soil formation

Out of the total proposed cost of various ecosystem services cost of climate regulations and habitat for wildlife are:

1. 6%
2. 50%
3. 25%
4. 10%

Forest management institute is situated in:

1. Jaipur
2. Bhopal
3. Jabalpur
4. Dehradun

The flow of materials from non living components to living components and back to the non living components in a more or less cyclic manner is called a:

1. Gaseous cycle
2. Sedimentary cycle
3. Biogeochemical cycle
4. Hydrologic cycle

Natural reservoir of phosphorus is:

1. Sea water
2. Animal bones
3. Rock
4. Fossils

Photosynthesis and respiration are central to which cycle?

1. The nitrogen cycle
2. The carbon cycle
3. The phosphorus cycle
4. The sulphur cycle

A forest community has been destroyed due to fire if new community is again developed on this area it is:

1. Primary succession
2. Secondary succession
3. Allogenic succession
4. Both (2) and (3)

Ecosystem functional characters which change during succession (i-Complexity of food chain and food web ii-Efficiency of energy use iii-Niches specialization iv-Nutrient conservation):

1. (i), (ii), (iii)
2. (ii), (iv), (iii)
3. (i), (ii), (iii), (iv)
4. (i), (ii), (iv)

Which biotic components mainly help in recycling of minerals:

1. Producers
2. Consumers
3. Decomposers
4. All the above

The primary succession refers to the development of communities on:

1. Freshly cleared crop field
2. Forest clearing after devastating fire
3. Pond, freshly filled with water after a dry phase
4. Newly exposed habitat with no record of earlier vegetation

The correct sequence of plants in a hydrosere is:

1. Oak → Lantana → Volvox → Hydrilla → Pistia → Scirpus
2. Oak → Lantana → Scirpus → Pistia → Hydrilla → Volvox
3. Volvox → Hydrilla → Pistia → Scirpus → Lantana → Oak
4. Pistia → Volvox → Scirpus → Hydrilla → Oak → Lantana

During progressive succession nutrient conservation and efficiency of energy use are:

1. Decreases
2. Increases
3. Constant
4. First increase then decrease

In which terms are the representation of the relationship between producers and consumers done?

1. Number
2. Age
3. Ecological
4. Succession

Energy pyramids are used to represent energy transfer in an ecosystem because energy is _______ between each trophic level.

1. Gained
2. Lost
3. Conserved
4. Either conserved or gained

Select the correct statements regarding the pyramids of ecosystem:

1. (a), (b), (c), (d)
2. (a), (b), (d)
3. (a), (b)
4. (a), (b), (c)

Which of the following pyramids always shows a steeper vertical gradient i.e. upward:

1. Pyramid of number
2. Pyramid of nutrients
3. Pyramid of biomass
4. Pyramid of energy

Mass of living matter at a tropic level in an area at any time is called:

1. Standing state
2. Standing crop
3. Detritus
4. Humus

If 20 J of energy is trapped at producer level, then how much energy will be available to peacock as food in the following chain? Plant → Mice → Snake → Peacock

1. 0.0002 J
2. 0.02 J
3. 0.002 J
4. 0.2 J

The mass of living material at a tropic level at a particular time is called:

1. Net primary productivity
2. Standing crop
3. Gross primary productivity
4. Standing state

If 10,000 Joule of energy is assimilated by producers in a ecosystem than how much amount of energy will be present in biomass of tertiary consumer:

1. 100 Joule
2. 1000 Joule
3. 10 Joule
4. 10,000 Joule

Frog that feeds on insects, is a:

1. Primary consumer
2. Secondary consumer
3. Tertiary consumer
4. Decomposer

Chemosynthetic bacteria found around deep-sea vents are examples of:

1. Producers
2. Decomposers
3. Primary consumers
4. Secondary producer

A plant, being eaten by a herbivore which in turn is eaten by a carnivore makes:

1. Food chain
2. Web of Food
3. Omnivores
4. Interdependence

The maximum energy is stored at following trophic level in any ecosystem:

1. Producers
2. Herbivores
3. Carnivores
4. Top carnivores

Word detritus includes:

1. Dead plants parts
2. Remains of animal
3. Animal excretion
4. All of these

Humification and mineralisation occur during:

1. Decomposition in the soil
2. Fragmentation in the soil
3. Leaching
4. Carbon fixation by plant

The process of mineralization by micro organisms helps in the release of:

1. Inorganic nutrients from humus
2. Both organic and inorganic nutrients from detritus
3. Organic nutrients from humus
4. Inorganic nutrients from detritus and formation of humus

Net primary productivity is the available biomass for the consumption to:

1. Herbivores
2. Decomposers
3. Primary producers
4. Top carnivore

Productivity at the second trophic level is always:

1. Greater than the productivity at the first trophic level
2. Less than the productivity at the first trophic level
3. Equals to the productivity at the first trophic level
4. Extremely variable compared to the productivity at the first trophic level

The following is (are) abiotic components of the ecosystem.

1. Soil
2. Carbon
3. Protein
4. All of the above

A pond/lake is:

1. A biome
2. Unnatural ecosystem
3. An artificial ecosystem
4. Community of plants and animals only

In an aquatic ecosystem, the organism present at the trophic level equivalent to cows in grasslands is:

1. Phytoplanktons
2. Large fishes
3. Sea gulls
4. Zooplanktons

Which of the following is the most stable ecosystem?

1. Mountain
2. Desert
3. Forest
4. Ocean

The role of an organism in the ecological system is known as:

1. Habitat
2. Herbivory
3. Niche
4. Interaction

Global ecosystem is divided into two basic categories, namely the:

1. Natural and man-made ecosystems
2. Biotic and abiotic ecosystems
3. Terrestrial and aquatic ecosystems
4. Both (2) and (3)

The functional unit of nature is called:

1. Community
2. Ecosystem
3. Population
4. Succession

Which of the following is/are example of man-made ecosystem?

1. Herbarium
2. Crop fields
3. Aquarium
4. Both (2) and (3)

An Ecosystem is a:

1. Group of components that interact with one another
2. Group of interacting species in one place at one time
3. Biological community and component of the physical environment with which the community interacts
4. Group of interacting chemicals and their cycles

Joint Forest Management concept was introduced in India during:

1. 1970s
2. 1980s
3. 1990s
4. 1960s

Slash and burn agriculture in North-Eastern states of India is also called:

1. Ley farming
2. Commercial agriculture
3. Jhum cultivation
4. All of these

The main cause of deforestation in the north-eastern states of India is:

1. Slash and burn agriculture
2. Jhum cultivation
3. Ash is used as a fertiliser
4. Both (1) and (2)

Which one of the following is a wrong statement? (Q37)

1. Most of the forests have been lost in tropical areas
2. Ozone in upper part of atmosphere is harmful to animals
3. Greenhouse effect is a natural phenomenon
4. Eutrophication is a natural phenomenon in freshwater bodies

Which of these statements is/are true about reforestation?

1. It is a process of restoring forest
2. It may occur naturally
3. It can be sped up by planting trees
4. All of these

Which of these statements is/are true about slash and burn agriculture?

1. Farmers cut down trees of the forest and burn the plant remains
2. Ash is used as fertilizer
3. Land is used for farming or cattle grazing
4. All the above

National Forest Policy (1988) of India has recommended ________ per cent forest cover for the plains and ________ per cent for the hills.

1. 60, 40
2. 33, 67
3. 40, 60
4. 67, 33

In human eye, cornea absorbs UV-B radiation, and a high dose of UV-B causes:

1. Inflammation of cornea
2. Cataract
3. Permanently damage to cornea
4. All of the above

Which one of the following is a wrong statement?

1. Most of the forests have been lost in tropical areas
2. Ozone in upper part of atmosphere is harmful to animals
3. Greenhouse effect is a natural phenomenon
4. Eutrophication is a natural phenomenon in freshwater bodies

Which of these is incorrect about ozone depletion?

1. CFCs releases 'Cl' atom causes degradation of O3
2. 'Cl' atoms acts as catalyst
3. 'Cl' atom is not consumed in the reaction
4. It is minimum over Antarctica region

Antarctic region has a large area of thinned ozone layer, commonly known as:

1. Dobson unit
2. Ozone hole
3. Black hole
4. All of these

Ozone degradation is done by:

1. DDT
2. CFCs
3. CH4
4. CO2

The thickness of ozone is measured in terms of:

1. BOD
2. D.O.
3. DU
4. ROP

Which one of the following pairs of gases are the major cause of Greenhouse Effect?

1. CO2 and N2O
2. CO2 and O3
3. CO2 and CO
4. CFCs and SO2

During the past century, the temperature of earth has increased by ________.

1. 0.6°C
2. 5°C
3. 6°C
4. 1°C

We can control global warming by the following means except:

1. Cut down use of fossil fuel
2. Slow down growth of human population
3. Improving efficiency of energy uses
4. Deforestation

The two gases making highest relative contribution to the greenhouse gases are:

1. CO2 and CH4
2. CH4 and NO2
3. CFCs and N2O
4. CO2 and N2O

Which gas contributes the maximum to the greenhouse effect?

1. CH4
2. CO2
3. CFCs
4. N2O

Which of these following methods is the most suitable for disposal of nuclear waste?

1. Shoot the waste into space
2. Bury the waste under Antarctic ice-cover
3. Dump the waste within rocks under deep ocean
4. Bury the waste within rocks deep below the Earth's surface

Bhopal gas tragedy of 1984 took place because methyl isocyanate reacted with:

1. DDT
2. ammonia
3. CO2
4. water

State the true statements for E-wastes:

1. Irreparable computers and other electronic goods are known as electronic wastes
2. E-wastes are buried in landfills or incinerated
3. Over half of the e-wastes generated in the developed world are exported to developing countries, mainly to China, India and Pakistan
4. All of these

ESP removes approx. ______% of particulate matter present in exhaust from a thermal power plant.

1. 60
2. 80
3. 99
4. 85

Rachel Carson's famous book 'Silent Spring' is related to:

1. Population explosion
2. Ecosystem management
3. Pesticide pollution
4. Noise pollution

A feature of integrated organic farming is that:

1. In this process, waste products from one process are recycled and used as nutrients for other processes
2. Industrial wastes are utilised for manufacturing products like polyblend
3. Chemical fertilisers are used to increase yield
4. Both (1) and (3)

Haryana Kisan Welfare Club was created by:

1. Ahmed Khan
2. Ramesh Chandra Dagar
3. Sundar Lal Bahuguna
4. State Government

The type of hazardous wastes generated by hospitals includes:

1. Disinfectants
2. Harmful chemicals
3. Pathogenic micro-organisms
4. All of the above

Polyblend, a fine powder of recycled modified plastic, has proved to be a good material for:

1. Making plastic sacks
2. Use as a fertilizer
3. Construction of roads
4. Making tubes and pipes

Sanitary landfills were adopted as the substitute for open-burning dumps, but it is not really much of a solution to manage solid waste in metro cities. Why?

1. The sites are getting filled due to increased garbage generation
2. There is a danger of seepage of chemicals, polluting the underground water
3. Both (1) and (2)
4. None of the above

Polyblend is:

1. a fine powder of recycled modified pesticide
2. a fine powder of recycled modified plastic
3. a fine powder of recycled modified fertilizer
4. a fine powder of recycled modified manure

The ideal modern sewage system is one in which:

1. Sanitary sewage water is collected and treated, but storm water is not
2. Individual home owners operate private septic systems on large lots
3. All sanitary sewage water & storm water is collected in a single sewer system and treated in a single treatment
4. All sanitary sewage water is collected separately from storm water and fully treated to remove all pollutants before the water is released to natural systems.

Limit of BOD prescribed by Central Pollution control Board for the discharge of industrial and municipal waste water into natural surface water, is:

1. < 30 ppm
2. < 3.0 ppm
3. < 10 ppm
4. 100 ppm

Choose the correct option about Water (Prevention and Control of Pollution) Act:

1. Government of India has passed the Water (Protection and Control of Pollution) Act
2. Water (Prevention and Control of Pollution) Act was made in 1974
3. Act was to safeguard our rivers only
4. All of these

What is A and B in this (graph showing dissolved oxygen and BOD):

1. A, B-Dissolved oxygen
2. A, B-BOD
3. A-Dissolved oxygen, B-BOD
4. A-BOD, B-Dissolved oxygen

Motor vehicle equipped with catalytic converters should use unleaded petrol because:

1. Lead activates the catalyst
2. Lead deactivates catalyst
3. Lead increases fuel efficiency
4. Lead decreases fuel efficiency

Concentration of DDT for zooplanktons and top trophic level is respectively in aquatic food chains if DDT is 0.003 ppb in water is:

1. 0.04 ppm, 25 ppm
2. 0.003 ppm, 2 ppm
3. 0.5 ppm, 2 ppm
4. 0.04 ppm, 2 ppm

The harmful effects of the air pollution on organism depends on:

1. Size of pollutant particles presents in air
2. Concentration of air pollutants
3. Duration of exposure and the organism
4. All of the above

______ is a major cause of air pollution in metro cities.

1. Factory
2. Automobiles
3. Smoking
4. Thermal power plant

The most widely used and effective device for removing particulate matter is

1. Arrester
2. Scrubber
3. Electrostatic precipitator
4. Converters

Pollution is any undesirable change in physical, chemical or biological characteristics of:

1. Air
2. Land
3. Water or soil
4. All of these