Practice Test

Q1) Term ecosystem was coined by: Show Answer

Q2) Biotic component of an ecosystem include: Show Answer

Q3) Which is the most stable ecosystem? Show Answer

Q4) In a biotic community, primary consumers are: Show Answer

Q5) If we completely remove the decomposers from an ecosystem, the ecosystem functioning will be adversely affected because: Show Answer

Q6) Food chain will end with: Show Answer

Q7) Which of the following is one way flow rather than a two way or cyclic flow? Show Answer

Q8) The importance of ecosystem lies in: Show Answer

Q9) The driving force for an ecosystem is: Show Answer

Q10) About how much of solar energy that falls on the leaves of a plant is converted to chemical energy by photosynthesis? Show Answer

Q11) Energy and nutrient enter a community by way of: Show Answer

Q12) A consumer whose carbon atoms have already passed through three species is a: Show Answer

Q13) Average annual precipitation in a desert biome is: Show Answer

Q14) A sequence of speices through which the organic molecules in a community pass is called: Show Answer

Q15) Savannahs are: Show Answer

Q16) Most food chains are composed of: Show Answer

Q17) A micro-climate is controlled mostly by factors associated with: Show Answer

Q18) In which of the following habitats does the diurnal temperature of soil surface vary most? Show Answer

Q19) A biome with high temperature, high rainfall no seasonal change and soil rich in mineral and humus is: Show Answer

Q20) A plant eaten by herbivorous animals which in turn is eaten by a carnivorous animal, it forms a: Show Answer

Q21) A pond is a: Show Answer

Q22) Which of the following communities would have trees? Show Answer

Q23) Which of the following has a vegetation structure with only one level? Show Answer

Q24) What type of pyramids are commonly referred to in the ecological studies? Show Answer

Q25) Which type of system does the earth along with its atmosphere constitute? Show Answer

Q26) Enrichment of habitat (say pond) with nutrients is called: Show Answer

Q27) Wolves and lion may be said to occupy the same trophic level because: Show Answer

Q28) About how much of the chemical energy within the producers tissue become chemical energy within herbivore tissue: Show Answer

Q29) The most diverse oceanic communities are in the: Show Answer

Q30) Which of the following aquatic ecosystem has very little primary productivity? Show Answer

Q31) Which of the following statement is true about ecological relationship? Show Answer

Q32) Light compensation zone refers to the zone: Show Answer

Q33) Aquatic ecosystem covers how much of the earth's surface? Show Answer

Q34) What are biotic components? Show Answer

Q35) The flora and fauna in lakes and ponds are: Show Answer

Q36) The source of energy in an ecosystem is: Show Answer

Q37) The energy storage at consumer level is called: Show Answer

Q38) Most hard competition for food, light and space is seen in: Show Answer

Q39) The leaves of Lotus bear stomata: Show Answer

Q40) The typical biome of an area having 20-40 inches of rainfall is: Show Answer

Q41) An ecosystem resists change because it is in a state of: Show Answer

Q42) Ecosystem has two components: Show Answer

Q43) The number of producers within a specified area would be maximum in: Show Answer

Q44) In an ecosystem, a big fish eats small fishes which eat water fleas supported by phytoplanktons. The water fleas in this ecosystem are: Show Answer

Q45) Which one of the following represents the largest population in an ecosystem? Show Answer

Q46) With regard to ecological food chain, man is a: Show Answer

Q47) The first link in a food chain is always a green plant because: Show Answer

Q48) A food chain is represented by: Show Answer

Q49) Organisms linked in a food chain represent: Show Answer

Q50) Free floating organisms are termed: Show Answer

Q51) The bottom-dwelling organisms are: Show Answer

Q52) First trophic level is represented by: Show Answer

Q53) In a grassland top consumers are: Show Answer

Q54) The food chain in which micro-organisms absorb and breakdown the energy rich compounds synthesized by the producers is: Show Answer

Q55) Lichens do not normally grow in cities: Show Answer

Q56) Primary productivity of ecosystem refers to: Show Answer

Q57) The individuals in the uppermost ring of pyramid represent the one with: Show Answer

Q58) The pyramid of number of individuals per unit area in a grassland ecosystem will be: Show Answer

Q59) Ecological niche is: Show Answer

Q60) Which of the following food chains is correct? Show Answer

Q61) 'Greenhouse effect' is: Show Answer

Q62) For recycling of materials which one is necessary? Show Answer

Q63) Energy flow in an ecosystem is: Show Answer

Q64) The pyramid of energy in a terrestrial ecosystem may be: Show Answer

Q65) Green plants are: Show Answer

Q66) Solar energy can be trapped to the maximum capacity by: Show Answer

Q67) The equilibrium of species is disturbed by: Show Answer

Q68) A food chain starts with: Show Answer

Q69) Biological equilibrium is an equilibrium among the: Show Answer

Q70) When the number of organisms at successive levels are plotted, they assume the shape of a pyramid. This is called: Show Answer

Q71) The salt concentration in open sea is about: Show Answer

Q72) The upper vertical zone upto the depth of 200 metres is known as: Show Answer

Q73) In a food chain, the largest number is of: Show Answer

Q74) Ecosystem is a self-sustanining unit because it consists of: Show Answer

Q75) A component of physical environment of an ecosystem is: Show Answer

Q76) In a food chain animals constitute the: Show Answer

Q77) Second order consumers are: Show Answer

Q78) Active swimmers are: Show Answer

Q79) Food web is constituted by: Show Answer

Q80) Vegetation found around the Mediterranean coast is called: Show Answer

Q81) An ecosystem is a complex interacting system of: Show Answer

Q82) Which of the following is truly a biome? Show Answer

Q83) The ecological niche of an organism is its: Show Answer

Q84) Which of the following forest is more diverse? Show Answer

Q85) The solar energy is trapped to the maximum by: Show Answer

Q86) Agroecosystem is a: Show Answer

Q87) Mangrove vegetation is found in: Show Answer

Q88) In grassland ecosystem the pyramid of energy is: Show Answer

Q89) Photic zone is spread upto a depth of: Show Answer

Q90) Chaparral occurs in Mediterranean area and rainfall occurs during? Show Answer

Q91) Daily tidal cycle recurs after: Show Answer

Q92) Pyramid of number is based on: Show Answer

Q93) Each couple should produce only two children which will help in: Show Answer

Q94) The trophic level of lion in a forest ecosystem is: Show Answer

Q95) About how much of net primary productivity of an aquatic ecosystem is eaten and digested by herbivores? Show Answer

Q96) Life without air is: Show Answer

Q97) Trophical dense forest is due to: Show Answer

Q98) Pyramid of energy is always: Show Answer

Q99) A kite eats mouse, mice live on grains. Hence the kite is a: Show Answer

Q100) The composition of soil air if affected by: Show Answer

Q101) Plants growing in alpine zone are short due to: Show Answer

Q102) Plants growing near the sea shore are generally resistant to: Show Answer

Q103) An anatomical feature is which exclusively develops to counter high velocity of wind: Show Answer

Q104) The classification of plant groups on the basis of temperature differentiating four zone such as megatherms was proposed by: Show Answer

Q105) Flowering is induced if germinating seeds are exposed to: Show Answer

Q106) The percentage of light from total solar input utilized by plants: Show Answer

Q107) Albedo value refers to: Show Answer

Q108) According to Geiger, the percentage of light reflected by the clouds is: Show Answer

Q109) The albedo value of a forest is around: Show Answer

Q110) The aquatic thermal strata where no temperature gradients are observed is called as: Show Answer

Q111) The alpine forests are classed under the plant group called: Show Answer

Q112) The optimum temperature for seedling growth in the upper Gangetic plains is around: Show Answer

Q113) When a plant of hot climate is transferred to colder regions, it gets an injury called: Show Answer

Q114) In western Himalayas, the Betula trees usually occur in: Show Answer

Q115) Annual carbon fixation by photosynthesis is: Show Answer

Q116) Annual world precipitation is: Show Answer

Q117) Maximum oxygen comes from: Show Answer

Q118) The main nitrogen reservoir in the biosphere is: Show Answer

Q119) The largest reservoir of sulphur in the biospere is the: Show Answer

Q120) The largest reservoir of phosphorus in the biosphere is the: Show Answer

Q121) Which one of the following pairs is a sedimentary type of biogeochemical cycle? Show Answer

Q122) Dense evergreen vegetation of broad sclerophyllous leaves and shrubs with fire resistant resinous plants is known as: Show Answer

Q123) Correct sequence in ascending order: Show Answer

Q124) Which of the following factor is responsible for animals to be successful: Show Answer

Q125) Perfect example of interdependence of plants and animals upon each other is: Show Answer

Q126) In any ecosystem or biological system there is transfer of energy at different trophic levels. The study of energy transfer at different trophic level is known as: Show Answer

Q127) Keystone species in ecosystem are those: Show Answer

Q128) Which of the following ecosystem has highest rate of gross primary production: Show Answer

Q129) The tendency of an organism to maintain internal equilibrium in response to any change in its environment is called or a tendency of biological systems to resist change so as to remain in a state of equilibrium is called: Show Answer

Q130) 10% energy transfer law in food chain was first given by: Show Answer

Q131) In India Tropical rain forests occur in: Show Answer

Q132) Pedology is the study of: Show Answer

Q133) When an organism is benefited without affecting the other is called: Show Answer

Q134) From first or lower trophic level to upper trophic level energy is degraded from high grade form to low grade form, it can be made clear from: Show Answer

Q135) In an ecosystem bacteria are considered as: Show Answer

Q136) A lake ecosystem is: Show Answer

Q137) The ecological pyramids are of: Show Answer

Q138) In which ecosystem species diversity is low: Show Answer

Q139) The succession as a result of changes in communities on earth's surface is called as: Show Answer

Q140) The climatic and edaphic factors working on a community is collectively known as: Show Answer

Q141) Individuals (organisms) of the same species inhabiting in a particualr locality constitute: Show Answer

Q142) During adverse season therophytes survive by: Show Answer

Q143) Plants that lack perennating buds and are annuals are placed in the life form: Show Answer

Q144) The concept of life form classes and biological spectrum was proposed by: Show Answer

Q145) The population of a place or an area tends to increase when: Show Answer

Q146) Eichhornia crassipes is a: Show Answer

Q147) Which one of the following is a correct food chain: Show Answer

Q148) Niche of a speices in an ecosystem refers to its: Show Answer

Q149) In a food chain of the largest population is that of: Show Answer

Q150) If forest cover is reduced to half, what is most likely to happen on a long term basis: Show Answer

Q151) The nature of climax community will depend upon: Show Answer

Q152) Extremities, tail and ear are relatively shorter in animals living in cold regions as compared to those inhabiting warmer zones. This is: Show Answer

Q153) Food levels in an ecosystem are called: Show Answer

Q154) First link in any food chain is green plant: Show Answer

Q155) Actively moving or swimming animals in aquatic systems are: Show Answer

Q156) Proper food chain is: Show Answer

Q157) The species losses in tropical countries is mainly due to: Show Answer

Q158) Which of the following can be considered an ecosystem? Show Answer

Q159) A large number of organic compounds can be decomposed by: Show Answer

Q160) Which is the main causative factor of desertification: Show Answer

Q161) The abundance of a species population within its habitat is called: Show Answer

Q162) Pyramid of numbers illustrates: Show Answer

Q163) In an ecosystem, there is a flow of energy from the producers to the consumers at different levels. This is known as the: Show Answer

Q164) Eutrophication in water results in: Show Answer

Q165) In a forest ecosystem, the fungi come under the category of: Show Answer

Q166) Identify the incorrect statement among the following statements on the effect of deforestation: Show Answer

Q167) The dominant second trophic level in a lake ecosystem is: Show Answer

Q168) Which of the following is the most characteristic feature of a xeric environment: Show Answer

Q169) Deciduous forests are characterised by: Show Answer

Q170) We refer to the following as the food chain: Show Answer

Q171) In an ecosystem there is flow of energy at different trophic levels. This is as follows: Show Answer

Q172) In a tiger reserve the tiger is placed in the: Show Answer

Q173) A rat feeding on potato tuber is: Show Answer

Q174) Lentic ecosystem occurs in which kind of water? Show Answer

Q175) Biome had organisms of various trophic level? Show Answer

Q176) Secondary proudcers are: Show Answer

Q177) Drought resistance of succulents is connected with: Show Answer

Q178) Ecosystem of a pond is: Show Answer

Q179) Mangrove of marshy Sundarbans is characterised by: Show Answer

Q180) Correct sequence in a food chain is: Show Answer

Q181) Peacock eats a snake and snake eats frog and frog eats insect while insect eats green plant, then position of peacock is: Show Answer

Q182) Organisms living at the bottom of a lake are: Show Answer

Q183) No animal can live: Show Answer

Q184) Hibernation occuring in certain animals is: Show Answer

Q185) In an ecosystem, trophic level of man is: Show Answer

Q186) Tip of an ecological pyramid is occupied by: Show Answer

Q187) Zooplanktonic forms are: Show Answer

Q188) Which of the following occurs in abiotic component of ecosystem? Show Answer

Q189) A treeless biome is: Show Answer

Q190) A man-made microecosystem is: Show Answer

Q191) Which one has always a steeper vertical gradient? Show Answer

Q192) Which one is exclusive xerophytic adaptation? Show Answer

Q193) Which one has evergreen vegetation and drought adapted animals? Show Answer

Q194) Which part of the world has high density of organisms? Show Answer

Q195) Viviparity and pneumatophores are features of: Show Answer

Q196) Trophic levels are formed by: Show Answer

Q197) An ecosystem has which of the following two components? Show Answer

Q198) The atmospheric humidity is measured by: Show Answer

Q199) The concept of ecological pyramids was developed by: Show Answer

Q200) From feeding on herbivorous insect is: Show Answer

Q201) Maximum biomass of autotrophs in oceans is made of: Show Answer

Q202) Terai forest is: Show Answer

Q203) Savannah is found commonly in: Show Answer

Q204) A recently discovered ecosystem is: Show Answer

Q205) Controlling factor in ecosystem is: Show Answer

Q206) Transition zone between two vegetational types is: Show Answer

Q207) Plant decomposers are: Show Answer

Q208) The ecosystem consists of: Show Answer

Q209) Desert can be converted into green land by planting: Show Answer

Q210) In food chain, lion is a: Show Answer

Q211) Which ecosystem shows maximum genetic diversity? Show Answer

Q212) Which of the following is correctly matched? Show Answer

Q213) Organisms found at the bottom of sea are: Show Answer

Q214) These belong to the category of primary consumers: Show Answer

Q215) If the high altitude birds become rare or extinct, the plants which may disappear along with them are: Show Answer

Q216) If by radiation all nitrogenase enzymes are inactivated, then there will be no: Show Answer

Q217) The Great Barrier Reef along the east coast of Australia can be catergorized as: Show Answer

Q218) Which one of the following pairs is mismatched? Show Answer

Q219) Which one of the following is correct matching of plant, its habit, and the forest type where it normally occurs? Show Answer

Q220) Energy transferred from one trophic level to another is: Show Answer

Q221) Maximum absorption of rainfall water is done by: Show Answer

Q222) The pyramid of energy is always upright for any ecosystem. This situation indicates the fact that: Show Answer

Q223) Which of the following is called as a detritivore? Show Answer

Q224) Which one of the following is not used for construction of ecological pyramids? Show Answer

Q225) Increased asthmatic attacks in certain seasons are related to: Show Answer

Q226) Consider the following statements concerning food chains: Show Answer

Q227) Large Woody Vines are more commonly found in: Show Answer

Q228) Which one of the following statements for pyramid of energy is incorrect, whereas the remainig three are correct? Show Answer

Q229) Mass of living matter at a trophic level in an area at any time is called: Show Answer

Q230) Of the total incident solar radiation the proportion of PAR is: Show Answer

Q231) In an aquatic ecosystem, which of the following are dominant in shallow water? Show Answer

Q232) Which of the following processes is involved in decomposition of detritus? Show Answer

Q233) What is the mean net primary productivity of tropical rain forest ecosystem? Show Answer

Q234) One of the following fall in the category of lowest productivity category? Show Answer

Q235) What is the key function of ecosystem? Show Answer

Q236) Photosynthetic efficiency is represented by: Show Answer

Q237) Which of the following is/are involved in the ammonification during nitrogen cycle? Show Answer

Q238) Mean annual rainfall (mm) in the tropical rain forest is: Show Answer

Q239) The primary productivity in grassland is directly related to: Show Answer

Q240) Which of the following is/are common trees and shrubs in savannah: Show Answer

Q241) Select the correct statement: Show Answer

Q242) Which of the following is an abiotic component of an ecosystem? Show Answer

Q243) Which of the following processes helps in nutrient conservation? Show Answer

Q244) Which of the following represents the sedimentary type of nutrient cycle? Show Answer

Q245) Which of the following is free living nitrogen fixing bacteria present in soil? Show Answer

Q246) What fraction of assimilated energy is used in respiration by the herbivore? Show Answer

Q247) Select the correct statement: Show Answer

Q248) Which of the following organisms and trophic levels is mismatched? Show Answer

Q249) Chemosynthetic bacteria found around deep-sea vents are examples of Show Answer

Q250) In an ecosystem, Show Answer

Q251) Primary productivity Show Answer

Q252) The open ocean and tropical rain forest are the two largest contributors to Earth's net primary productivity because Show Answer

Q253) Productivity in terrestrial ecosystems is affected by Show Answer

Q254) Secondary productivity Show Answer

Q255) Which of the following is not true of a pyramid of productivity? Show Answer

Q256) Biogeochemical cycles are global for elements Show Answer

Q257) Which of these processes is incorrectly paired with its description? Show Answer

Q258) Carbon cycles relatively rapidly except when it is Show Answer

Q259) What do primary producers have available to convert into biomass? Show Answer

Q260) Which of the following trophic levels would have the largest numbers of individuals? Show Answer

Q261) Which of the following elements is not a major component of living systems? Show Answer

Q262) Most of Earth's nitrogen is in Show Answer

Q263) The gas that is removed from the atmosphere by plants and algae is Show Answer

Q264) Most of the world's carbon is found Show Answer

Q265) Photosynthesis and respiration are central to which cycle? Show Answer

Q266) In the past 150 years there has been a major new input to the carbon cycle. What is it? Show Answer

Q267) Nitrogen is often in short supply in terrestrial ecosystems. Why? Show Answer

Q268) The phosphorus cycle differs from the carbon cycle in that Show Answer

Q269) Which of the following statements regarding the movement of energy and nutrients through ecosystem is true? Show Answer

Q270) Which of the following changes would not result in an increase in net primary production? Show Answer

Q271) On average, how much of the energy assimilated at one trophic level is converted to production the next trophic level (excluding the conversion of sun-light into chemical energy by plants) Show Answer

Q272) Which of the following always has a "pyramidal" shape, that is decreasing values at higher trophic levels? Show Answer

Q273) Which of the following statements regarding the hydrological cycle is false? Show Answer

Q274) In biogeochemical cycles, elements that cycle fastest Show Answer

Q275) Which of the following biogeochemical cycles is characterized by a major reservoir that is gaseous, and a major inorganic form that can only be utilized by a small group of bacteria and cyanobacteria? Show Answer

Q276) Which of the following biogeochemical cycles is characterized by a form which is a major greenhouse gas? Show Answer

Q277) Which of the following biogeochemical cycles lacks a gaseous phase? Show Answer

Q278) Which of the following biogeochemical cycles has a gaseous phase released by volcanoes and fumaroles? Show Answer

Q279) Which of the following biogeochemical cycles has a major reservoir in sedimentary rock? Show Answer

Q280) In the human-induced condition called eutrophication, the main biogeochemical cycle that is altered is the ______ cycle, and the effect is to create ______ conditions and decrease species diversity. Show Answer

Q281) Slow rate of decomposition of fallen logs in nature is due to Show Answer

Q282) In the human-induced condition called acid precipitation, the main biogeochemical cycles that are altered are the ______ cycles, and one effect in lakes is the _______ of populations of nitrifying bacteria. Show Answer

Q283) Which of the following is not a part of either gross or net primary production in plants? Show Answer

Q284) Which of the following statements about food chains and energy flow through ecosystems is false? Show Answer

Q285) Assuming that the energy transfer efficiency between trophic levels is 10%, how much grain would be required to produce 70 kg of human biomass if the grain is eaten by cows and the cows are eaten by humans? Show Answer

Q286) Grasslands can support greater grazing rates by herbivores than forests because Show Answer

Q287) An inverted pyramid of ______ may occasionally be observed in _______ communities. Show Answer

Q288) Which of the following is not an objective of integrated pest management? Show Answer

Q289) Which of the following could not be considered an ecosystem? Show Answer

Q290) In which of the following compartments of the global ecosystem would circulation of materials be affected by Earth's revolution around the sun? Show Answer

Q291) Which of the following statements about biogeochemical cycles is not true? Show Answer

Q292) Which of the following is true about the amount of sunlight and heat arriving on Earth? Show Answer

Q293) The total amount of energy that plants assimilate by photosynthesis is called Show Answer

Q294) The amount of energy reaching an upper trophic level is determined by Show Answer

Q295) Select the correct combination of statements (I - IV) regarding the characteristics of productivity.
I. The rate of biomass production is called productivity and is expressed in terms of a kcal m^(-2).
II. Gross primary productivity is rate of production of biomass during photosynthesis.
III. Gross primary productivity minus respiration loss is called net primary productivity.
IV. Primary productivity depends only on the plant species inhabiting a particular area. The correct statements are Show Answer

Q296) Fill in the blanks, in the following simplified model of a nutrient cycle. Show Answer

Q297) The given figure best represents Show Answer

Q298) Valuable, practical services that help to preserve ecosystems performed by nature are called _____. Show Answer

Q299) Identify the incorrect statement from the following Show Answer

Q300) The correct definition of ecosystem is Show Answer

Q301) When a peacock eats snakes which eats insects thriving on green plants, the peacock is Show Answer

Q302) In an ecosystem, the population of Show Answer

Q303) Which is correct sequence in the food chain? Show Answer

Q304) When a big fish eats a small fish which eats water fleas supported by phytoplankton, the water fleas are Show Answer

Q305) Graphical representation of biomass relationship between the producer and the consumers is called Show Answer

Q306) A food chain consists of Show Answer

Q307) In a forest ecosystem, green plants are Show Answer

Q308) In a food chain, herbivores are Show Answer

Q309) Percentage of nitrogen in air is about Show Answer

Q310) The transfer of energy in food chain is Show Answer

Q311) A vegetarian food habits of man help in getting Show Answer

Q312) The gaseous portion of outer earth surface is Show Answer

Q313) Which of the food chain will be advantageous in terms of energy? Show Answer

Q314) Ecological niche refers to Show Answer

Q315) Which of the following biome has largest number of species? Show Answer

Q316) Chapparal occurs in area Show Answer

Q317) Name the sedimentary cycle that has a small gaseous components Show Answer

Q318) The secondary productivity means Show Answer

Q319) Which one of the following has the largest population in a food chain? Show Answer

Q320) Second most important trophic level is a lake is Show Answer

Q321) Secondary producers are Show Answer

Q322) What is the percentage of photosynthetically active radiation (PAR), if incident solar radiation is considered 100%. Show Answer

Q323) Identify the incorrect statement from the following. Show Answer

Q324) Which of the following process will be most adversely affected if microorganisms are removed from a forest ecosystem? Show Answer

Q325) Food chains differ from food webs in that -
A. food chains are a single sequence of who eats whom in a community.
B. food chains better represent the entire community.
C. food webs represent the complex interaction among food chain.
D. food chain is the flow of energy in a population. Show Answer

Q326) Which of the following factors influence communities -
A. Climate
B. Species interaction
C. Feeding relationships among organisms
D. Succession Show Answer

Q327) Which of following is/are trend (s) in ecological succession -
A. an increase in complexity of species
B. an increase in productivity
C. an increase in community stability and species diversity
D. a decrease in non-living organic materials. Show Answer

Q328) Primary productivity depends upon -
A. The plant species inhabiting a particular area.
B. Availability of nutrients.
C. Photosynthetic capacity of plants. Show Answer

Q329) Which of the following ecological pyramids may be upright or inverted?
A. pyramid of energy
B. pyramid of number
C. pyramid of biomass
D. none. Show Answer

Q330) Which of the following statement(s) is/are correct about biogeochemical cycle -
A. Carbon and nitrogen cycle faster than phosphorus cycle.
B. All biogeochemical cycles include both organisms and non-living components.
C. Most elements remain longest in the living portion of their cycle.
D. The chemical elements used by organisms in large quantities cycle back and forth between organisms and environment. Show Answer

Q331) The cycle most important for modifying temperature fluctuation is Show Answer

Q332) Which is/are true regarding ecosystem?
A. Self sufficient unit.
B. Cyclic exchange of materials between living beings and environment.
C. Only requirement is input of energy.
D. Characterized by a major vegetation type. Show Answer

Q333) Which of the following are artificial aquatic ecosystems?
A. large dams and reservoirs
B. lakes and canals
C. fishery tanks and aquaria
D. river Show Answer

Q334) The phosphates remain outside the natural cycle for a long time Show Answer

Q335) The term used to describe all the species and physical factor at a site is the Show Answer

Q336) The amount of energy that is left to build bodies is termed Show Answer

Q337) A. P-cycling depends only on biological processes.
B. In general, food chains are more stable then food webs.
C. The food chain that depends on decomposing plant or animal matter is the detritus.
D. Humans can feed at several trophic levels and are classified as omnivores. Show Answer

Q338) Combustion of fossil fuels most directly affects the Show Answer

Q339) Which of the following include(s) ecosystem services -
A. Purification of air and water by forests.
B. Forests mitigate droughts and flood.
C. Forests act as store house of carbon.
D. Forests influence hydrological cycle. Show Answer

Q340) Select the correct statement(s) -
A. The factors affecting decomposition are chemical nature of detritus and the climatic factors.
B. It detritus is rich in lignin and chitin decomposition is very fast.
C. Decomposition is very slow if the detritus is rich in nitrogen.
D. Detritus is the raw material for decomposition. Show Answer

Q341) A. The amount of living matter (biomass) present at every trophic level is called standing crop.
B. Saprophytes are not given any in ecological pyramids.
C. Ecological pyramid does not account the same species belonging to two or more trophic levels.
D. Humus is reservoir of nutrients. Show Answer

Q342) Which of the following is/are incorrect -
A. All ecosystems are constant in size.
B. In nature food chains exist, not food web.
C. Flow of energy in ecosystem is linear.
D. Gene flow occurs between 2 different population (of 2 species) Show Answer

Q343) Ecological efficiency at each trophic level of a particular ecosystem is 20%. If green plants of the ecosystem capture 100 units of energy, about how many units of energy will be available to support herbivores Show Answer

Q344) Ecological succession is Show Answer

Q345) Succession is a Show Answer

Q346) A dynamic equilibrium is established between community and environment when Show Answer

Q347) Which is correct? Show Answer

Q348) Herbivores are Show Answer

Q349) Food chain consists of Show Answer

Q350) Autotrophs are Show Answer

Q351) In which of the following areas does the primary succession occur? Show Answer

Q352) Which of the following statements about the food chain is false? Show Answer

Q353) Go through the following statements.
A. Primary productivity of all ecosystem is a constant.
B. The annual net primary productivity of the whole of the biosphere is 17 million tons (dry weight) of organic matter.
C. Net primary productivity is the amount of biomass available for consumption by carnivores.
D. Secondary productivity is defined as the rate of formation of new organic matter by decomposers.
E. Primary productivity depends on the plant species inhabiting a particular area.
Which of the above the statements about productivity is true ? Show Answer

Q354) Arrange the following ecosystems in increasing order of mean NPP (Tonnes/ha/year)
A. Tropical deciduous forest
B. Temperate coniferous forest
C. Tropical rain forest
D. Temperate deciduous forest Show Answer

Q355) The energy invested in the production of new tissue by autotrophic organisms is termed Show Answer

Q356) Which of the following is true of net primary production? Show Answer

Q357) Which of the following statements is incorrect? Show Answer

Q358) Which of the following is NOT a reason why productivity declines from one trophic level to the next? Show Answer

Q359) Which of the following is NOT true of a food web? Show Answer

Q360) Which of the following is NOT a hypothesis for why food-chain length is limited? Show Answer

Q361) Which of the following is NOT a basic aspect of biogeochemical cycling? Show Answer

Q362) Several of the major human impacts are farming, logging, burning and soil erosion. They all result in accelerated nutrient loss by what common mechanism? Show Answer

Q363) In a comparative study of grassland ecosystem and pond ecosystem it may be observed that Show Answer

Q364) Why are changes in the global carbon cycle important? Show Answer

Q365) Go through the statements.
A. In terrestrial ecosystem, maximum energy is present in T1.
B. In grassland ecosystem, the pyramid of biomass is upright.
C. In pyramid of food, the producers occupy the base.
D. Energy flow in an ecosystem is bidirectional.
E. If all green plants of earth are destroyed, all animals shall die ultimately.
F. The typical biome of an area having 50 to 100 cm of rainfall is grassland.
How many of the above statement(s) is wrong? Show Answer

Q366) The important step in the process of decomposition in order is Show Answer

Q367) In trophic level of our ecosystem we belong to Show Answer

Q368) Which of the following is false?
I. Quantity of biomass in a trophic level at a particular period is called standing crop.
II. The energy content in a trophic level is determined by considering a few individuals of a species in that trophical level.
III. The succession that occurs in nearly cooled lava is called primary succession.
IV. Rate of succession is faster in the secondary succession.
V. Phytoplanktons are the pioneers in aquatic succession. Show Answer

Q369) The component of the ecosystem are seen to function as a unit when you consider which of the following aspects -
A. Productivity
B. Decomposition
C. Energy flow
D. Nutrient cycle Show Answer

Q370) Which of the following is correct? Show Answer

Q371) Which of the following is wrong? Show Answer

Q372) Which of the following statements is correct?
A. An important characteristic of all communities is that composition and structure constantly change in response to the changing environmental condition.
B. These changes lead finally to a community that is in equilibrium with it self and not the environment and that is called climax community.
C. The entire sequence of communities that successively change in a given area are called sere(s). Show Answer

Q373) The two major differences between carbon and phosphorus cycle are -
A. Atmospheric inputs of phosphorus through rainfall are much smaller than carbon inputs.
B. Atmospheric inputs of phosphorus through rainfall are much greater than carbon inputs.
C. Gaseous exchange of phosphorus between organic and environment is not negligible.
D. Gaseous exchange of phosphorus between organic and environment are negligible. Show Answer

Q374) With which of four levels of biological organization of Ecology is basically concerned?
A. Organisms
B. Species
C. Family
D. Population
E. Community
F. Biomass Show Answer

Q375) Which of the following is in order of importance of the most influencing factor in life of organisms? Show Answer

Q376) Which of the following statements are correct?
A. Detritivores break down detritus into smaller particles. This process is called fragmentation.
B. By the process of leaching, water soluble inorganic nutrients go down into the soil horizon and get participated as unavailable salts.
C. Bacterial and fungal enzymes degrade detritus into simpler inorganic substances. This process is called catabolism. Show Answer

Q377) Which of the following statements regarding decomposition is false?
I. Warm and moist favours decompositions.
II. Decomposition rate is slower if detritus is rich in chitin and lignin.
III. Earthworm is detritus.
IV. Precipitation of soluble inorganic nutrients in the soil horizon as unavailable salt is called mineralization.
V. Detritus is the raw material for decomposition. Show Answer

Q378) Dead plant remains such as leaves, bark, flowers and dead remains of animals, including fecal matter constitutes Show Answer

Q379) Which of the following represents an incomplete ecosystem? Show Answer

Q380) Which of the given below pyramids represents the variation in biomass at different trophic levels in pond ecosystem? Show Answer

Q381) Choose the odd one out w.r.t. succession Show Answer

Q382) During nutrient immobilization, nutrients get incorporated in the body of living organisms like Show Answer

Q383) Net primary productivity Show Answer

Q384) The amount of biomass or organic matter produced per unit area over a time period by plants during photosynthesis is called primary production, which is expressed as Show Answer

Q385) Researchers have put an average price tag of US $ 33 trillion a year on the fundamental ecosystems services, which are largely taken for granted because they are free. This is nearly how many times the value of the global gross national product. Show Answer

Q386) The overall productivity in terrestrial ecosystems is limited by Show Answer

Q387) The path that an element takes as it moves from abiotic systems through living organisms and back again is referred to as its Show Answer

Q388) Which of the following is not one of the three aspects studied in biogeochemical cycling? Show Answer

Q389) Which of the following most often limits the rate at which nutrients move through an ecosystem? Show Answer

Q390) Perturbation of which of the following cycles contributes most to global warming? Show Answer

Q391) Why are economists trying to quantify the dollar value of ecosystem services? Show Answer

Q392) In most food chains, Show Answer

Q393) Assume that the green plants in an ecosystem produce 1000 grams of dry mass per square meter par year and there is an efficiency of 10 percent in each transfer of energy from one trophic level to the next. How many total grams of dry mass will produce by the tertiary consumers per square meter per year? Show Answer

Q394) The problem(s) with the notion that if all humans became vegetarians, then the earth could support more people is that Show Answer

Q395) Of the five elements that are the most important constituents of living things, the only one that requires the action of microorganisms to enter the living system is Show Answer

Q396) Relationships in an ecosystem can be depicted through Show Answer

Q397) In upright pyramid of biomass, herbivores occupy the position Show Answer

Q398) Which one is inverted pyramid? Show Answer

Q399) Pyramid of numbers in grassland ecosystem is Show Answer

Q400) An ecological pyramid of biomass is the representation of the ecosystem's Show Answer

Q401) Both, hydrarch and xerarch successions lead to Show Answer

Q402) Mr. X is eating yoghurt. For this he is occupying the trophic level. Show Answer

Q403) The breakdown of detritus into smaller particles by earthworm is a process called Show Answer

Q404) Which of the following would probably have the greatest total biomass? Show Answer

Q405) Which one of the species is probably carnivorous? Show Answer

Q406) Which species is (a) decomposer? Show Answer

Q407) If a pyramid of number, representing an ecosystem of a large fresh water pond, the number of primary consumers is Show Answer

Q408) The free floating organisms of an open sea and the shore are collectively called Show Answer

Q409) Which creatures are direct or indirect food of all creatures on the ocean's surface? Show Answer

Q410) In plant succession when climax is reached the net productivity Show Answer

Q411) In autogenic succession Show Answer

Q412) Find out the correct older of succession levels in xerarch. Show Answer

Q413) Which one of the following ecosystem types has the highest annual net primary productivity? Show Answer

Q414) In a pyramid of number, in a grassland ecosystem, the largest population is that of Show Answer

Q415) Some of the stages in the hydrarch are labelled as -
A. Marsh meadow stage
B. Reed swamp stage
C. Submerged plant stage
D. Phytoplankton stage
E. Submerged free floating plant stage
Identify the choice that represents the correct sequence of these stages. Show Answer

Q416) Which one of the following regarding ecological pyramid is not correct? Show Answer

Q417) The bacteria which attack dead animals are Show Answer

Q418) Which one of the following is considered as pioneer community in xerarch? Show Answer

Q419) A detrivorous animal of economic importance is Show Answer

Q420) The dominant second trophic level, in a lake ecosystem is Show Answer

Q421) The correct sequence of plants in a hydrosere is Show Answer

Q422) Which one of the following types of organisms occupy more than one trophic level in a pond ecosystem? Show Answer

Q423) Which of the following statements is false?
I. Pyramids of energy and yearly biomass production can never be inverted, since this would violate the laws of thermodynamics.
II. Pyramids of standing crop and numbers can be inverted, since the amount of organisms at any one time does not indicate the amount of energy flowing through the system.
III. There are certain limitations of ecological pyramids such as it does not take into account the same species belonging to two or more trophic levels.
IV. Saprophytes are not given any place in ecological pyramids even though they play a vital role in the ecosystem. Show Answer

Q424) Read the following statements carefully.
I. Primary succession is a very slow process taking thousands of years for the climax to be reached.
II. Energy at a higher trophic level is always more than at a lower level.
III. Bacterial and fungal enzymes degrade detritus into simpler inorganic substances. This process is called fragmentation.
IV. All succession whether taking place in water or on land, proceeds to a similar climax community - the mesic.
Which of the two above statements are correct? Show Answer

Q425) In the process of ecological succession, organisms that are present at one stage change Show Answer

Q426) Amount of carbon in the environment Show Answer

Q427) The four main processes of the water cycle are Show Answer

Q428) In recycling of mineral elements within an ecosystem, the responsible direct causal organism are called Show Answer

Q429) Animals with a constant body temperature such as mammals and birds require more food than do animals with a changing body temperature such as reptiles and fish. Why? Show Answer

Q430) The most energy-efficient method to feed large human populations such as China is to eat Show Answer

Q431) A. GFC is major conduit of energy flow in aquatic ecosystem.
B. Food chain maintains stability in an ecosystem by providing alternate organisms at different trophic level.
C. DFC may be connected to GFC. Show Answer

Q432) A term biotype means Show Answer

Q433) The pyramid of number of a parasitic food chain in forest ecosystem is Show Answer

Q434) Which one of the following statements is correct for secondary succession? Show Answer

Q435) In terms of percentage of total forest cover, the most abundant type of the forest in India is Show Answer

Q436) The rate of formation of new organic matter by rabbit in a grassland, is called Show Answer

Q437) The important steps, in the process of decomposition are Show Answer

Q438) In an ecosystem, at a particular time standing crop Show Answer

Q439) In a pyramid of biomass, if the total dry weight (kg/ml) of primary producers is about 809 it will decrease at teritary consumer level up-to Show Answer

Q440) Which one of the following is not a functional unit of an ecosystem Show Answer

Q441) The upright pyramid of number is absent in Show Answer

Q442) Which one of the following processes during decomposition is correctly described? Show Answer

Q443) A sedentary sea anemone gets attached to the shell lining of hermit crab. The association is Show Answer

Q444) Natural reservoir of phosphorus is Show Answer

Q445) Secondary productivity is rate of formation of new organic matter by Show Answer

Q446) The total mass of nutrient matter that makes up the Earth is _______. Show Answer

Q447) The net primary productivity of an ecosystem can be viewed as the Show Answer

Q448) Which of the following is incorrect? Show Answer

Q449) The removal of 'Keystone' species will affect Show Answer

Q450) Anthropogenic ecosystems Show Answer

Q451) Select the correct statements. Show Answer

Q452) The rate of biomass production and the rate of production of organic matter during photosynthesis are called respectively Show Answer

Q453) Pick out the correct option from (A) to (D).
A. Primary succession begins in areas where natural communities have been destroyed.
B. Hydrarch succession takes place in water.
C. The climax community is the community that is in near equilibrium with the immediate environment.
D. In newly cooled lava secondary succession occurs. Show Answer

Q454) Which one of the following group of organisms can represent every trophic level in a ecosystem? Show Answer

Q455) Vertical distribution of different species occupying different levels in a biotic community is known as Show Answer

Q456) Secondary succession takes place on/in Show Answer

Q457) In an ecosystem the rate of production of organic matter during photosynthesis is termed as Show Answer

Q458) Most animals are tree dwellers in a Show Answer

Q459) Most animals that live in deep oceanic waters are Show Answer

Q460) In which of the following both pairs have correct combination? Show Answer

Q461) During ecological succession Show Answer

Q462) Which of the following is a characteristic feature of cropland ecosystem? Show Answer

Q463) Which of the following would appear as the pioneer organisms on bare rocks? Show Answer

Q464) The primary producers of the deep-sea hydrothermal vent ecosystem are Show Answer

Q465) Ecotone is Show Answer

Q466) 'Edge effect' is observed in case of Show Answer

Q467) Community dynamics is related to Show Answer

Q468) Which of the following organisms in the given food web act as a predator and a prey? Show Answer

Q469) Which of the following organism in the given food wen acts as a secondary consumer? Show Answer

Q470) Read the given statements and select the correct option. Statement 1 : Herbivores are also called as first order consumers. Statement 2 : Herbivores obtain their food directly from plants. Show Answer

Q471) Percentage of photosynthetically active radiation (PAR) in the incident solar radiation is Show Answer

Q472) Percentage of photosynthetically active radiation (PAR) that is captured by plants in synthesis of organic matter is Show Answer

Q473) Select the correct food chain. Show Answer

Q474) Read the following statements and select the correct ones. (i) A given species may occupy more than one trophic level in the same ecosystem at the same time. (ii) Productivity of an aquatic ecosystem is less than that of a terrestrial ecosystem. (iii) Producers constiture the first trophic level of a detritus food chain. Show Answer

Q475) If 10 joules of energy is available at the producer level, then amount of energy persent at the level of seconday consumers is Show Answer

Q476) Organisms which are associated with first as well as third trophic level are Show Answer

Q477) In a grassland ecosystem, if the number of primary producers is approximately 6 million plants, the number of top carnivores (in million), which may be supported by it, may be Show Answer

Q478) Which one of the following animals may occupy more than one trophic levels in the same ecosystem at the same time? Show Answer

Q479) Study the following statements concerning food chains and select the correct ones. (i) Removal of 80% tigers from an area resulted in greatly increased growth of vegetation. (ii) Removal of most of the carnivores resulted in an increased population of deers. (iii) The length of food chains is generally limited to 3-4 trophic levels due to energy loss. (iv) The length of food chains may vary from 2 to 8 trophic levels. Show Answer

Q480) In an aquatic ecosystem, the organism present at the trophic level equivalent to cows in grasslands is Show Answer

Q481) Which one of the following is not a correct match of the term and its description? Show Answer

Q482) Which one of the following is the most productive ecosystem? Show Answer

Q483) 'Calcifuges' are the plants growing in Show Answer

Q484) Which one of the following aspects is not a component of functional unit of ecosystem? Show Answer

Q485) In a comparative study of grassland ecosystem and pond ecosystem, it may be observed that Show Answer

Q486) __________ is the rate of production of organic matter by consumers. Show Answer

Q487) Primary productivity depends upon Show Answer

Q488) Read the given statements and select the correct option.
Statement 1: Net primary productivity is less than the gross primary productivity. Statement 2: Net primary productivity is equal to the gross primary productivity minus the respiration losses. Show Answer

Q489) The annual net primary productivity of the whole biosphere is approximately Show Answer

Q490) Productivity at the second trophic level is always Show Answer

Q491) The biomass available for consumption by the herbivores and the decomposers is called Show Answer

Q492) Which one of the following exhibits least productivity? Show Answer

Q493) Which of the following is not a characteristic of humus? Show Answer

Q494) During the process of decomposition Show Answer

Q495) Fragmentation, leaching and catabolism are some of the important steps of decomposition. Study the following statements ((i), (ii) and (iii)) regarding these and select the correct option.
(i) Detritivores (e.g., earthworm) break down detritus into smaller particles.
(ii) Water soluble inorganic nutrients go down into soil horizon and get precipitated as unavailable salts.
(iii) Decomposers (e.g., bacteria and fungi) excrete digestive enzymes and degrade detritus into simpler inorganic substances. Show Answer

Q496) Rate of decomposition depends upon Show Answer

Q497) Decomposers are also called as Show Answer

Q498) Read the given statements and select the correct option.
Statement 1: In an aquatic ecosystem, pyramid of biomass is inverted.
Statement 2: Biomass depends upon reproductive potential and longevity of individuals. Show Answer

Q499) Mr. X is eating curd/yoghurt. For this food intake in a food chain he should be considered as occupying Show Answer

Q500) Primary succession occurs on Show Answer

Q501) Successions that occur on soils or areas which have recently lost their community are referred to as Show Answer

Q502) In lithosere, foliose lichens make the conditions favourable for the growth of Show Answer

Q503) Select the correct sequence of succession in a pond. Show Answer

Q504) Correct sequence of stages of succession on a bare rock is Show Answer

Q505) Read the given statements and select the correct option.
Statement 1: Pioneer community is the stable and final biotic community of an ecological succession.
Statement 2: Pioneer community has maximum diversity and niche specialization. Show Answer

Q506) An ecosystem which can be easily damaged but can recover after some time if damaging effect stops will be having Show Answer

Q507) The second stage of hydrosere is occupied by plants like Show Answer

Q508) Read the given statements and select the correct option.
Statement 1: Major reservoirs of phosphorus are phosphate rocks and fossil bone deposits laid down in the past geological ages.
Statement 2: During weathering of rocks, minute amounts of these phosphates dissolve in soil solution and are absorbed by the roots of the plants. Show Answer

Q509) Select the pairs of sedimentary biogeochemical cycles.
I. Hydrogen cycle and water cycle
II. Phosphorus cycle and sulphur cycle
III. Calcium cycle and magnesium cycle
IV. Carbon cycle and nitrogen cycle Show Answer

Q510) About 70% of total global carbon is found in Show Answer

Q511) Which one of the following is not a gaseous biogeochemical cycle in ecosystem? Show Answer

Q512) Read the given statements and select the correct option.
Statement 1: Global water cycle does not involve the living organisms.
Statement 2: In this cycle, water circulates between hydrosphere and atmosphere. Show Answer

Q513) Source of maximum sulphur is Show Answer

Q514) Which of the following is most important in water cycle? Show Answer

Q515) Out of the total proposed cost of various ecosystem services, cost of climate regulations and habitat for wildlife are Show Answer

Q516) Given below is a table of factors affecting microbial decomposition. ('+' means 'favouring' and '-' means inhibiting or lowering). Select the correct option. Show Answer

Q517) Decomposers like fungi and bacteria are
(i) autotrophs
(ii) heterotrophs
(iii) saprotrophs
(iv) chemo-autotrophs.
Choose the correct answer. Show Answer

Q518) The process of mineralisation by micro organisms helps in the release of Show Answer

Q519) An inverted pyramid of biomass can be found in which ecosystem? Show Answer

Q520) Which of the following is not a producer? Show Answer

Q521) Which of the following ecosystems is most productive in terms of net primary production? Show Answer

Q522) Pyramid of numbers is Show Answer

Q523) Approximately how much of the solar energy that falls on the leaves of a plant is converted to chemical energy by photosynthesis? Show Answer

Q524) Among the following, where do you think the process of decomposition would be the fastest? Show Answer

Q525) How much of the net primary productivity of a terrestrial ecosystem is eaten and digested by herbivores? Show Answer

Q526) During the process of ecological succession the changes that take place in communities are Show Answer

Q527) Climax community is in a state of Show Answer

Q528) Among the following bio-geo-chemical cycles which one does not have losses due to respiration? Show Answer

Q529) The sequence of communities of primary succession in water is Show Answer

Q530) The reservoir for the gaseous type of bio-geo chemical cycle exists in Show Answer

Q531) If the carbon atoms fixed by producers already have passed through three species, the trophic level of the last species would be Show Answer

Q532) Which of the following type of ecosystem is expected in an area where evaporation exceeds precipitation, and mean annual rainfall is below 100mm? Show Answer

Q533) The zone at the edge of a lake or ocean which is alternatively exposed to air and immersed in water is called Show Answer

Q534) Edaphic factor refers to Show Answer

Q535) Which of the following is an ecosystem service provided by a natural ecosystem? Show Answer

Q536) Assertion: Oceans are a low productivity ecosystems despite occupying about 70% of the earth's surface.
Reason: In aquatic ecosystems, productivity is limited by light which decreases with increasing water depth. Show Answer

Q537) Assertion: Amount of organic matter synthesized by producers per unit time and per unit area during the process of photosynthesis is referred to as net primary productivity. Reason: Primary productivity is usually high and sustained throughout the year in temperate areas due to abundance of sunlight. Show Answer

Q538) Assertion: Temperature and soil moisture are the important climatic factors that regulate the process of decomposition.
Reason: Warm and moist environments favour decomposition whereas low temperature and anaerobiosis inhibit decomposition. Show Answer

Q539) Assertion: The loss of biologically useful energy as heat with every energy transfer in a food chain is a consequence of the second law of thermodynamics.
Reason: Energy does not remain trapped permanently in any organism, it is either passed on to higher trophic level or becomes available to detrivores and decomposers after the organism dies. Show Answer

Q540) Assertion: In a marine aquatic ecosystem, the biomass of phytoplanktons (producers) at any given time, is lower than the biomass of zooplanktons (primary consumers).
Reason: Phytoplanktons are consumed almost as rapidly as they are formed and thus have shorter life spans. Show Answer

Q541) Assertion: Aquatic herbivores are usually more productive as compared to terrestrial herbivores.
Reason: Due to their small size and lack of structural tissues, the phytoplanktons achieve faster growth rates and are more nutritious to heterotrophs than their terrestrial counterparts. Show Answer

Q542) Assertion: Primary succession occurs over a primarily bare area where there was no living matter from the very beginning.
Reason: During primary succession, reproductive structures of the previous occupants give rise to a new seral community as soon as the conditions become favourable. Show Answer

Q543) Assertion: Crustose lichens, in a lithosere, secrete organic acids causing the weathering of rocks so that minerals essential for proper growth of lichens are released.
Reason: Early colonists in a primary succession are usually lichens, which suggests that colonization is easier when an organism has a mutualistic association. Show Answer

Q544) Assertion: Secondary succession always involves a predictable sequence of species and ends up with the same climax community as existed prior to the disturbance.
Reason: A pond cannot be considered as a self-sustained ecosystem as it does not possess all the structural and functional components which work as a unit in an ecosystem. Show Answer

Q545) Assertion: During an ecological succession, the number of species increases, the community biomass increases and the community's ratio of respiration to photosynthesis also increases.
Reason: At climax community of an ecological succession, the rate of photosynthesis of a community is almost equal to the rate of respiration. Show Answer

Q546) Assertion: Herbivores are also called as key industry animals because they convert plant matter into animal matter.
Reason: Decomposers play a pivotal role in the ecosystem and they indirectly support the producers. Show Answer

Q547) Assertion: Sedimentary nutrient cycles of phosphorus, calcium, magnesium etc. are considered as imperfect cycles.
Reason: These cycles get more easily disrupted by local disturbances as the bulk of material remains in the relatively inactive and immobile reservoir on the earth's crust. Show Answer

Q548) Assertion: The process of nitrification involves the decomposition of proteins of dead plants and animals, and nitrogenous wastes like urea, uric acid etc. of animals to ammonia.
Reason: Nitrification is carried out by putrefying bacteria such as Bacillus ramosus, B. vulgaris etc. Show Answer