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Biology M.C.Q (1 Marks)

Ecosystems · Jharkhand Board (JAC) STD 12 Science (Jharkhand - English Medium). 261 questions.

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M.C.Q (1 Marks)

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50 questions · auto-graded multiple-choice test.

MCQ 11 Mark
Two different species cannot live for long duration in the same niche or habitat. This law is.
  • A
    Allen’s law.
  • ✓
    Gause’s hypothesis.
  • C
    Dollo’srule.
  • D
    Weismann’s theory.
Answer
Correct option: B.
Gause’s hypothesis.
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MCQ 21 Mark
The primary succession in a sere is a:
  • A
    Sub sere
  • B
    Meso sere
  • ✓
    Pioneer sere
  • D
    None of the above
Answer
Correct option: C.
Pioneer sere
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MCQ 31 Mark
Which of the following is free$-$living aerobic non$-$photosynthetic nitrogen$-$fixing bacte$-$ rium?
  • A
    Rhizobium.
  • ✓
    Azotobacter.
  • C
    Nostoc.
  • D
    Azospirillum.
Answer
Correct option: B.
Azotobacter.
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MCQ 41 Mark
Second most important trophic level in a lake:
  • ✓
    Zooplankton.
  • B
    Phytoplankton
  • C
    Benthos.
  • D
    Neuston.
Answer
Correct option: A.
Zooplankton.
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MCQ 51 Mark
An ecosystem is a:
  • A
    Group of components that interact with one another.
  • B
    Group of interacting species in one place at one time.
  • ✓
    Biological community and component of the physical environment with which the community interacts.
  • D
    Group of interacting chemicals and their cycles.
Answer
Correct option: C.
Biological community and component of the physical environment with which the community interacts.
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MCQ 61 Mark
Plant succession is a $.............$ process.
  • ✓
    Definite
  • B
    Haphazard
  • C
    Unimportant
  • D
    Harmful
Answer
Correct option: A.
Definite
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MCQ 71 Mark
Plant community development is termed as:
  • A
    Corrosion
  • B
    Erosion
  • ✓
    Succession
  • D
    Possesion
Answer
Correct option: C.
Succession
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MCQ 81 Mark
In a pond ecosystem, the food chain starts with:
  • A
    Zooplanktons.
  • B
    Small insects.
  • ✓
    Phytoplanktons.
  • D
    Small fishes.
Answer
Correct option: C.
Phytoplanktons.
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MCQ 91 Mark
Each trophic level has a certain mass of living material at a particular time is known as:
  • A
    Catabolism.
  • ✓
    Standing crop.
  • C
    Humification.
  • D
    Primary productivity
Answer
Correct option: B.
Standing crop.
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MCQ 101 Mark
Decomposers like fungi and bacteria are:
  1. Autotrophs.
  2. Heterotrophs.
  3. Saprotrophs.
  4. Chemo$-$autotrophs.
  5. Choose the correct answer.
  • ✓
    $ii$ and $iii.$
  • B
    $i$ and $ii.$
  • C
    $i$ and $iv.$
  • D
    $i$ and $iii.$
Answer
Correct option: A.
$ii$ and $iii.$
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MCQ 111 Mark
Keystone species are:
  • A
    Species belonging to same period
  • ✓
    Species that determine structure of biotic community
  • C
    Species reproducing sexually
  • D
    Species recorded only in the fossil state
Answer
Correct option: B.
Species that determine structure of biotic community
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MCQ 121 Mark
Which type of association is found in be$-$tween entomophilous flower and pollinat$-$ing agent?
  • ✓
    Mutualism.
  • B
    Commensalism.
  • C
    Cooperation.
  • D
    Co$-$evolution.
Answer
Correct option: A.
Mutualism.
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MCQ 131 Mark
Which one of the following is one of the characteristics of a biological community?
  • A
    Natality.
  • ✓
    Stratification.
  • C
    Mortality.
  • D
    None of these.
Answer
Correct option: B.
Stratification.
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MCQ 141 Mark
In which condition, the gene ratio remains constant for any species?
  • A
    Sexual selection.
  • ✓
    Random mating.
  • C
    Mutation.
  • D
    Gene flow.
Answer
Correct option: B.
Random mating.
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MCQ 151 Mark
The greatest biomass of autotrophs in the world’s oceans is that of:
  • A
    Benthic brown algae, coastal red algae and daphnids.
  • B
    Benthic diatoms and marine viruses.
  • C
    Sea grasses and slime molds.
  • ✓
    Free$-$floating micro$-$algae, cyanobacteria and nanoplankton.
Answer
Correct option: D.
Free$-$floating micro$-$algae, cyanobacteria and nanoplankton.
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MCQ 161 Mark
What is the annual net primary productivity of whole biosphere?
  • ✓
    $170$ billion tons $($dry weight$)$ of organic matter.
  • B
    $165$ billion tons $($dry weight$)$ of organic matter.
  • C
    $160$ billion tons $($dry weight$)$ of organic matter.
  • D
    $155$ billion tons $($dry weight$)$ of organic matter.
Answer
Correct option: A.
$170$ billion tons $($dry weight$)$ of organic matter.
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MCQ 171 Mark
Last stable community is succession which depends on climate is:
  • A
    Seral community
  • ✓
    Climax community
  • C
    Poineer community
  • D
    None of the above
Answer
Correct option: B.
Climax community
The gradual change in the species structure of an ecological community is known as ecological succession. A climax community is the final community formed when the ecological succession becomes stable. It remains relatively unchanged until destroyed by an event such as fire or human interference. It is also known as a stable biological community.
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MCQ 181 Mark
The sphere of living matter together with water, air, and soil on the surface of the earth is called $.........$
  • A
    Lithosphere
  • ✓
    Biosphere
  • C
    Hydrosphere
  • D
    Atmosphere
Answer
Correct option: B.
Biosphere
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MCQ 191 Mark
A progressive series of changes in plant and animal life of an area from initial colonization is known as:
  • A
    Evolution
  • ✓
    Succession
  • C
    Specialisation
  • D
    Selection
Answer
Correct option: B.
Succession
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MCQ 201 Mark
The pyramid of energy in a forest ecosystem is:
  • ✓
    Always upright
  • B
    Always inverted
  • C
    Both upright and inverted
  • D
    None of the above
Answer
Correct option: A.
Always upright
Ecological pyramid is the graphic representation of an ecological parameter $($number, biomass or energy$).$
The ecological pyramid can be upright, inverted or spindle shaped. The pyramid of energy gives graphic representation of flow of energy in different trophic levels. It is always upright because only $10$ percent of energy is transferred from one trophic level to the next.
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MCQ 211 Mark
The total energy fixed by a gram plant $($Cicer arietinum$)$ in an ecosystem as a whole is called:
  • A
    Primary production
  • ✓
    Gross production
  • C
    Secondary production
  • D
    Tertiary production
Answer
Correct option: B.
Gross production
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MCQ 221 Mark
Energy flow in ecosystem is:
  • ✓
    Unidirectional.
  • B
    Multidirectional.
  • C
    Bidirectional.
  • D
    None of these.
Answer
Correct option: A.
Unidirectional.
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MCQ 231 Mark
If the carbon atoms fixed by producers already have passed through three species, the trophic level of the last species would be:
  • A
    Secondary consumer.
  • B
    Tertiary producer.
  • ✓
    Tertiary consumer.
  • D
    Scavenger.
Answer
Correct option: C.
Tertiary consumer.
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MCQ 241 Mark
Which one of the following pairs is mis$-$matched?
  • A
    Savanna $-$ Acacia trees.
  • ✓
    Prairie $-$ Epiphytes.
  • C
    Tundra $-$ Permafrost.
  • D
    Coniferous forest $-$ Evergreen trees.
Answer
Correct option: B.
Prairie $-$ Epiphytes.
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MCQ 251 Mark
The final stable community in ecological succession is:
  • A
    Seral community
  • B
    Pioneer communiy
  • C
    Ecosere
  • ✓
    Climax community
Answer
Correct option: D.
Climax community
The climax community is stable, self$-$perpetuating and final community appearing in an area at the end of biotic succession, which is in perfect harmony with the climate of the area.
The vegetation in that particular area has been reached to a stable condition after ecological succession.
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MCQ 271 Mark
Which one of these is a sedimentary cycle ?
  • ✓
    Phosphorous
  • B
    Hydrogen
  • C
    Oxygen
  • D
    Nitrogen
Answer
Correct option: A.
Phosphorous
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MCQ 281 Mark
A mutually beneficial association necessary for survival of both partners are:
  • ✓
    Mutualism$/$ symbiosis.
  • B
    Commensalism.
  • C
    Amensalism.
  • D
    Both $(a)$ and $(b).$
Answer
Correct option: A.
Mutualism$/$ symbiosis.
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MCQ 291 Mark
In a biotic community, the most important factor for survival of an animal is:
  • A
    Day length.
  • B
    Soil moisture.
  • ✓
    Green food.
  • D
    Predators
Answer
Correct option: C.
Green food.
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MCQ 301 Mark
Ecosystem may be defined as $..........?$
  • A
    Group of plants which act as the energy suppliers
  • B
    Group of organisms which form population
  • ✓
    Functional unit of environment
  • D
    All of the above
Answer
Correct option: C.
Functional unit of environment
The ecosystem is a segment of nature or biosphere consisting of a community of living beings and the abiotic or physical environment both interacting and exchanging materials between them. The ecosystem is defined as a functional unit of environment, which is independent and self$-$sustaining due to various interactions between abiotic and biotic components and different organisms among themselves.
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MCQ 311 Mark
Pyramid of energy in a forest ecosystem is:
  • A
    Always inverted
  • ✓
    Always upright
  • C
    Both upright and inverted depending on ecosystem
  • D
    First upright then inverted
Answer
Correct option: B.
Always upright
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MCQ 321 Mark
Zooplanktons represent which trophic level in an aquatic ecosystem?
  • A
    $T_1$ level.
  • ✓
    $T_2$ level.
  • C
    $T_4$ level.
  • D
    $T_3$ level.
Answer
Correct option: B.
$T_2$ level.
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MCQ 331 Mark
The zone at the edge of a lake or ocean which is alternatively exposed to air and immersed in water is called:
  • ✓
    Littoral zone.
  • B
    Lentic one.
  • C
    Benthic zone.
  • D
    Pelagic zone.
Answer
Correct option: A.
Littoral zone.
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MCQ 341 Mark
The natural process by which different groups or communities colonize the same area over a period of time in a definite sequence is called:
  • A
    Adaptation
  • B
    Variation
  • ✓
    Succession
  • D
    Biological rhythm
Answer
Correct option: C.
Succession
The transition in the species composition of a given area is called ecological succession.
This takes place due to the change in the environmental conditions in a geographical area.
During succession, some species colonise an area and their populations become more numerous, whereas populations of other species decline and even disappear.
The time scale can be decades $($for example, after a wildfire$),$ or even millions of years after a mass extinction.
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MCQ 351 Mark
Which one of the following statements is correct for secondary succession?
  • A
    It is similar to primary succession, except that it has a relatively fast pace.
  • B
    It begins on a bare rock.
  • ✓
    It occurs on a deforested site.
  • D
    It follows primary succession.
Answer
Correct option: C.
It occurs on a deforested site.
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MCQ 361 Mark
Climax community is in a state of:
  • A
    Non$-$equilibrium.
  • ✓
    Equilibrium.
  • C
    Disorder.
  • D
    Constant change.
Answer
Correct option: B.
Equilibrium.
Climax community is in a state of equilibrium.
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MCQ 371 Mark
Which of the following habitats is most unsuitable for primary productivity?
  • A
    Meadow
  • B
    Forest river bank
  • ✓
    Cave
  • D
    Pond
Answer
Correct option: C.
Cave
The plants or the other autotrophic organisms which can prepare food require sunlight. In a cave, there will be very less availability of sunlight and hence primary productivity due to photosynthesis by green plants will be very low. Hence, a cave ecosystem is most unsuitable for primary productivity.
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MCQ 381 Mark
Succession showing changes in communities at a place is called:
  • A
    Geographical succession
  • ✓
    Biotic succession
  • C
    Physiographic succession
  • D
    Climate succession
Answer
Correct option: B.
Biotic succession
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MCQ 391 Mark
Which of the following is an ecosystem service provided by a natural ecosystem?
  • A
    Pollutant absorption and reduction of the threat of global warming.
  • B
    Prevention of soil erosion.
  • C
    Cycling of nutrients.
  • ✓
    All of the above.
Answer
Correct option: D.
All of the above.
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MCQ 401 Mark
Among the following bio$-$geo$-$chemical cycles which one does not have losses due to respiration?
  • A
    Sulphur.
  • B
    Nitrogen.
  • C
    Phosphorus.
  • ✓
    All of the above.
Answer
Correct option: D.
All of the above.
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MCQ 411 Mark
Which of the following statements is correct for secondary succession?
  • A
    It begins on a bare rock.
  • B
    It occurs on a deforested area.
  • C
    It follows primary succession.
  • ✓
    It is similar to primary succession, but has arelatively fast pace.
Answer
Correct option: D.
It is similar to primary succession, but has arelatively fast pace.
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MCQ 421 Mark
Which of the following event does not lead into secondary succession?
  • A
    All organisms that existed are lost
  • ✓
    Where no living organisms ever existed
  • C
    Abandoned crop field
  • D
    Land affected by flood
Answer
Correct option: B.
Where no living organisms ever existed
The appearance of living organisms on disturbed or damaged habitat is referred to as secondary succession.
Primary succession occurs in a barren land where no life existed before.
So, flooded land abandoned croplands and the area where organisms existed before exhibit the secondary succession.
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MCQ 431 Mark
Presence of plants arranged into well defined vertical layers depending on their height can be seen best in:
  • A
    Grassland.
  • B
    Temperate Forest.
  • ✓
    Tropical Rain Forest.
  • D
    None of these.
Answer
Correct option: C.
Tropical Rain Forest.
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MCQ 441 Mark
Which one of the following pairs in mismatched?
  • A
    Savanna $-$ acacia trees.
  • ✓
    Prairie $-$ epiphytes.
  • C
    Coniferous forest $-$ evergreen trees.
  • D
    Tundra $-$ permafrost.
Answer
Correct option: B.
Prairie $-$ epiphytes.
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MCQ 451 Mark
Among the following, where do you think the process of decomposition would be the fastest?
  • ✓
    Tropical rain forest.
  • B
    Antarctic.
  • C
    Dry arid region.
  • D
    Alpine region.
Answer
Correct option: A.
Tropical rain forest.
In tropical rain forest, there is ambient temperature, good moisture and plenty of sugar in detritus. Due to this, rate of decomposition would be fast.
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MCQ 461 Mark
The amount of energy flow in an ecosystem generally:
  • ✓
    Decreases at each higher trophic level.
  • B
    Increase at each higher trophic level.
  • C
    Remains same at each trophic level.
  • D
    Is different in different food chains.
Answer
Correct option: A.
Decreases at each higher trophic level.
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MCQ 471 Mark
Bamboo plant is growing in a far forest then what will be the trophic level of it?
  • ✓
    First trophic level $(T_1).$
  • B
    Second trophic level $(T_2).$
  • C
    Third trophic level $(T_3).$
  • D
    Fourth trophic level $(T_4).$
Answer
Correct option: A.
First trophic level $(T_1).$
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MCQ 481 Mark
Total amount of energy trapped by green plants in food is called $.........?$
  • ✓
    Gross primary production
  • B
    Net primary production
  • C
    Standing crop
  • D
    Standing state
Answer
Correct option: A.
Gross primary production
The total quantity of solar energy converted into chemical energy by green plant is known as gross primary production.
A portion of gross production is used by the producers for their various metabolic activities. The remainder of energy after utilization is called as net primary production.
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MCQ 491 Mark
Choose the correct match Bladderwort, sun$-$ dew, venus fly trap:
  • A
    Nepenthes, Dionea, Drosera.
  • B
    Nepenthes, Utricularia, Vanda.
  • ✓
    Utricularia, Drosera, Dionea.
  • D
    Dionea, Trapa, Vanda.
Answer
Correct option: C.
Utricularia, Drosera, Dionea.
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MCQ 501 Mark
Primary productivity:
  • A
    Is equal to the standing crop of an ecosystem.
  • B
    Is greatest in freshwater ecosystems.
  • ✓
    Is the rate of conversion of light to chemical energy in an ecosystem.
  • D
    Is inverted in some aquatic ecosystems
Answer
Correct option: C.
Is the rate of conversion of light to chemical energy in an ecosystem.
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M.C.Q (1 Marks) - Biology STD 12 Science Questions - Vidyadip