"Complete competitors cannot coexist" is true for
1.Primary succession
2.Secondary succession
3.Competitive exclusion
4.Character displacement
A renewable exhaustible natural resource is
1.Petroleum
2.Coal
3.Forests
4.Minerals
An ecosystem which can be easily damaged but can recover after some time if damaging effect stops will be having
1.High stability and high resilience
2.Low stability and low resilience
3.High stability and low resilience
4.Low stability and high resilience
Bell-shaped polygonal pyramid indicates
1.Low percentage of young individuals
2.Moderate percentage of young individuals
3.High percentage of young individuals
4.Low percentage of old individuals
Community is
1.Species structure and diversity index of an area
2.Biomass
3.Autotrophic and heterotrophic components
4.All of these
Competition is severe in a population that has a distribution which is
1.Uniform
2.Random
3.Non-random
4.Irregular
Identify the possible link "A" in the following food chain: Plant → insect → frog → "A" → Eagle
1.Parrot
2.Rabbit
3.Cobra
4.Wolf
In a population, if the rate of addition of new members is higher than the rate of individuals lost, it shows
1.Exponential growth
2.Declined growth
3.Zero population growth
4.none of these
In an aquatic ecosystem, the trophic level equivalent to cows in grasslands is
1.Zooplankton
2.Phytoplankton
3.Benthos
4.Nekton
In an ecosystem Biotic factors affect the survival of an organism in that ecosystem. They include
1.competition for food and water
2.competition for shelter
3.co-operation to help find food
4.All of the above
In ecological succession from pioneer to climax community, the biomass shell
1.No relation
2.Increase and then decrease
3.Decrease
4.Increase continuously
Individuals of a species which occur in a particular area constitute
1.Fauna
2.Population
3.Flora
4.Flora and Fauna
Information about birth rate, death rate, sex ratio, age distribution etc. of a population is obtained from
1.Mortality rate
2.Life table
3.Natality table
4.Both (A) and (C)
Insectivorous plants are adopted to soils
1.Deficient in nitrogenous compounds
2.Deficient in water
3.Rich in water
4.Deficient in trace elements
Carbon dioxide is called green-house gas because it is
1.Transparent to sunlight but traps heat
2.Transparent to heat but traps sunlight
3.Used in green-house to increase plant growth
4.Transparent to both sunlight and heat
Large Woody Vines are more commonly found in
1.Alpine forests
2.Temperate forests
3.Mangroves
4.Tropical rainforests
Lead is one of the most serious environmental pollutants which affects
1.Water
2.Soil
3.Air
4.Noise
lf there was no CO2 in the atmosphere, the earth temperature would be
1.Less than the present
2.Same as present
3.Higher than the present
4.Dependent on O2 content of air
Lichens indicate pollution by
1.Ozone
2.SO2
3.NO3
4.CO
Major aerosol pollutant present in the jet plane emission is
1.Carbon monoxide
2.Carbon tetrachloride
3.Chlorofluorocarbon
4.Sulphur dioxide
Maximum deposition of DDT will occur in
1.Phytoplankton
2.Crab
3.Eel
4.Sea gull
Maximum threat to the world is from
1.Global warming
2.Ozone hole
3.Water pollution
4.Soil erosion
Minamata disease is due to pollution of
1.Industrial waste mercury into fishing water
2.Oil spill in water
3.Organic waste into drinking water
4.Arsenic into the atmosphere
Montreal Protocol aims at
1.Control of CO2 emission
2.Reduction of ozone depleting substances
3.Biodiversity conservation
4.Control of water pollution
Most abundant water pollutant is
1.Industrial wastes
2.Pesticides
3.Detergents
4.Ammonia
Most harmful environmental pollutants are
1.Natural nutrients in excess
2.Human organic wastes
3.Nonbiodegradable chemicals
4.Waste animal feed
Organisms that can tolerate and thrive in a wide range of temperatures are called
1.Eukaryotic organisms
2.Stenothermal
3.Eurythermal
4.None of these
Pheromones, the chemical messengers produced by certain exocrine glands of skin, affect
1.Skin color
2.Breast
3.Genitalia
4.Mutual behaviour of members of a species
Plant succession occurring in a sandy area is
1.Xerosere
2.Halosere
3.Psammosere
4.Hydrosere
The age of pyramid with broad base indicates
1.High percentage of old individuals
2.Low percentage of young individuals
3.High percentage of young individuals
4.Low percentage of old individuals
The atmosphere of big metropolitan cities is polluted most by
1.Automobile exhausts
2.Radio-active fall out
3.Household waste
4.Pesticides residue
The final stable community in ecological succession is
1.Climax
2.Sere
3.Pioneers
4.Carnivores
The maximum amount of water that a soil can hold, by capillary action is called
1.Wilting point
2.Water potential
3.Osmotic potential
4.Field capacity
The role of an organism in the ecological system is known as
1.Niche
2.Habitat
3.Herbivory
4.Interaction
The slow rate of decomposition of fallen logs in nature is due to their:
1.Poor nitrogen content
2.Low moisture content
3.Anaerobic environment around them
4.Low cellulose content
The type of ecosystem with the highest mean plant productivity is
1.Tropical rain forest
2.Temperate grassland
3.Desert
4.Tundra
The ultraviolet radiations in the stratosphere are absorbed by
1.SO2
2.Oxygen
3.Ozone
4.Argon
The upright pyramid of number is absent in
1.Graasland
2.Pond
3.Lake
4.Forest
Trichoderma harzianum has proved a useful microorganism for:
1.Reclamation of wastelands
2.Bioremediation of contaminated soils
3.Biological control of soil-borne plant pathogens
4.Gene transfer in higher plants
Trophic levels in ecosystem is formed by :
1.only herbivores
2.Only bacteria
3.only plants
4.Organisms linked in food chain
Ultra-violet light causes
1.Photodynamic action
2.Sticky metaphases
3.Formation of pyrimidines
4.Destruction of hydrogen bonds between complementary DNA strands
Which factor of ecosystem includes plants, animals and microorganisms?
1.Biotic factors
2.Direct factors
3.Indirect factors
4.Abiotic factors
Which of the environmental pollutions can cause birth defects?
1.Smog
2.SO2
3.CO
4.Radioactivity
Which of the following pollutants is discharged by jet planes?
1.Photo-chemical oxidants
2.Frog
3.Smog
4.Aerosols
Which of the followings take part in symbiosis of lichen?
1.Fungus-Fungus
2.Alga-Alga
3.Alga-Fungus
4.Fungus-Gymnosperm
Which one of the following ecosystem types has the highest annual net primary productivity?
1.Tropical deciduous forest
2.Tropical rain forest
3.Temperate deciduous forest
4.Temperate evergreen forest
Which one of the following is not a bioindicator of water pollution
1.Blood-worms
2.Sludge-worms
3.Sewage fungus
4.Stone flies
Which one of the following is not a functional unit of an ecosystem?
1.Productivity
2.Stratification
3.Energy flow
4.Decomposition
Which one of the following is not a gaseous biogeochemical cycle in ecosystem?
1.Nitrogen cycle
2.Carbon cycle
3.Sulphur cycle
4.Phosphorus cycle
Which one of the following is the correct percentage of the two (out of the total of 4) green house gases that contribute to the total global warming?
1.CO2 40%,CFCs 30%
2.CFCs 14%, Methane 20%
3.Methane 20%, N2O 18%
4.N2O 6%, CO2 86%