Q.1
Which is an example of positive feed back? .... .... [C.P.M.T.2000]
  • a) Seasonal growth
  • b) Vessel diameter and blood pressure
  • c) Allosteric inhibition of enzymes
  • d) Both A and B
Q.2
In an aquatic ecosystems, trophic levels equivalent to cows in grassland is .... .... [D.P.M.T. 2009]
  • a) Nekton
  • b) Phytoplankton
  • c) Benthos
  • d) Zooplankton
Q.3
Ecosystem contains .... ..... [M.P.P.M.T.2011]
  • a) Food web
  • b) Food chain
  • c) Both A and B
  • d) None
Q.4
Eroded soils are .... .... [C.P.M.T.1989]
  • a) Devoid of plants nutrients
  • b) Richer in plant nutrients
  • c) Unaltered in plant nutrients
  • d) fit for agriculture
Q.5
A habitat with long severe winter and growing season of a few months of summer forms ..... ..... [C.P.M.T.1991]
  • a) Grasslands
  • b) Tundra ecosystem
  • c) Taiga
  • d) Savannah
Q.6
Decomposition rate is slow if detritus is rich in .... .... [ Kerala 2012]
  • a) Nitrogen
  • b) Humus
  • c) Sugars
  • d) Lignin and chitin
Q.7
In lake ecosystem, the pyramid of biomass is generally .... .... [Pb.P.M.T.2007]
  • a) Spindle - shaped
  • b) Inverted
  • c) Upright
  • d) Horizontal
Q.8
Out of nutrient cycles of sulphur (a) phosphorous (b) carbon (c) nitrogen (d) which one is sedimentary .... .... [Kerala 2010]
  • a) a only
  • b) b only
  • c) c only
  • d) a and b only
Q.9
Pheretima and its close relatives obtain nourishment from .... .... [C.B.S.E. 2012]
  • a) Decaying fallen leaves and soil organic matter
  • b) Soil insects
  • c) Sugarcane roots
  • d) Small pieces of fresh fallen leaves of Maize and others
Q.10
Which is correct food chain in grassland? .... .... [H.P.P.M.T.2005]
  • a) Grass → snake → insect → deer
  • b) Gras → wolf → deer → buffalo
  • c) Bacteria → grass → rabbit → wolf
  • d) Grass → insect → frog → snake
Q.11
Quercus species are dominant component of .... .... [C.B.S.E. 2008]
  • a) Temperate forest
  • b) Tropical rain forest
  • c) Alpine forest
  • d) Scrub forest
Q.12
Biotic community along with its interacting physical environment comprises .... ..... [D.P.M.T.1997]
  • a) Phytosociology
  • b) Phytogeography
  • c) Ecosystem
  • d) Ecology
Q.13
Pyramid of energy is always upright indicating that .... .... [K.C.E.T. 2005]
  • a) Producers have the lowest energy
  • b) Carnivores have a better energy efficiency than herbivores
  • c) Energy conversion efficiency is same for all trophic levels
  • d) Herbivores have a better energy conversion efficiency than Carnivores
Q.14
An inexhaustible non-conventional energy source is .... .... [Har P.M.T.2004]
  • a) Coal
  • b)Petroleum
  • c) Solar radiation
  • d) Electricity from nuclear plants
Q.15
Nitrogen fixation is ..... ..... [B.H.U.2000]
  • a) Nitrogen → ammonia
  • b) Nitrogen → nitrates
  • c) Nitrogen → amino acid
  • d) Both A and B
Q.16
Deforestation is the major causal agent of .... .... [M.P.P.M.T. 11989]
  • a) Depletion of natural resources
  • b) Environmental pollution
  • c) Desertification of habitat
  • d) Genetic erosion
Q.17
Tiger lies at the apex of food chain because .... .... [Odisha 2002]
  • a) Tiger has maximum biomass
  • b) Tiger feeds on a number of herbivores which feed on number of plants
  • c) Tiger has many enemies
  • d) Tiger is omnivores
Q.18
If the decomposers become extinct, the most severely affected would be .... .... [B.H.U.2003]
  • a) Non-cycling of minerals
  • b) Damage to nitrogen fixation
  • c) Biomagnification
  • d) Carnivores will be starved
Q.19
American water plant that has become a troublesome water weed in India is .... .... [C.B.S.E 1993]
  • a) Cyperus rotundus
  • b) Eichhornia crassipes
  • c) Trapa latifolia
  • d) Trapa bispinosa
Q.20
Flow of energy declines as it passes from lower to higher trophic level. This is explained by .... .... [C.P.M.T.1992]
  • a) First law of thermodynamics
  • b) Second law of thermodynamics
  • c) Newton's second law
  • d) Newton's third law
Q.21
Which of the following is not used for construction of ecological pyramids? .... .... [C.B.S.E.2006]
  • a) Fresh weight
  • b) Dry weight
  • c) Number of individuals
  • d) Rate of energy flow
Q.22
Match the following .... ..... [Kerala 2008]
a. tropical rain forest hopea
b. tropical deciduous forest shorea
c. temperate broad leaf forest quercus
d. temperate coniferous forest picea
  • a) a - 2, b - 1, c - 4, d - 3
  • b) a - 1, b - 2, c - 3, d - 4
  • c) a - 3, b - 2, c - 1, d - 4
  • d) a - 1, b - 2, c - 4, d – 3
Q.23
In the absence of decomposers, ecosystem functioning is adversely affected due to .... ..... [C.B.S.E. 1995]
  • a) Blocking of energy flow
  • b) blocking of mineral cycling
  • c) Blocking of solar energy to herbivores
  • d) Rate of decomposers of other components will increase
Q.24
Soil conservation is .... .... [C.B.S.E 1989]
  • a) Conversion of sterile soil into fertile one
  • b) Aeration of soil
  • c) Erosion of soil
  • d) Protection against loss
Q.25
Crystalline rocks are natural sources of biogenetic element .... .... [Kerala 2000]
  • a) Carbon
  • b) Sodium
  • c) Phosphorus
  • d) Magnesium
Q.26
Rate of formation of organic matter by rabbit in a grassland is .... .... [C.B.S.E. 2012]
  • a) Gross primary production
  • b) net primary production
  • c) Net productivity
  • d) Secondary productivity
Q.27
Savannah is found commonly in .... .... [Pb.P.M.T.2011]
  • a) U.S.A
  • b) U.S.S.R
  • c) Australia
  • d) India
Q.28
Who have tried to put price tag on nature's life support services .... .... [H.P.P.M.T.2011]
  • a) Robert Costanza
  • b) Nile Perch
  • c) Herbert Boyer
  • d) Ram Deo Misra
Q.29
The accompanying figure represents an ecological pyramids. It is .... .... [ AIIMS 2005]
unit-10_ch-1_que_no-419_img_no1.png
  • a) Pyramid of numbers in grassland
  • b) Pyramid of biomass in fallow land
  • c) Pyramid of biomass in lake
  • d) Energy pyramid in a spring
Q.30
In the pyramid of numbers find out the correct possibilities .... .... [ CBSE 2012]
unit-10_ch-1_que_no-420_img_no1.png
  • a) Level PC is rats and level SC is cat
  • b) Level PP is phytoplankton in sea and level TC is whale
  • c) Level PP is pipal tree and level SC is sheep
  • d) Level PC is insects and level SC is small insectivorous birds
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