Well structured WBBSE Class 9 Life Science MCQ Questions Chapter 5.1 Ecology and Ecological Organisations can serve as a valuable review tool before exams.
Ecology and Ecological Organisations Class 9 WBBSE MCQ Questions
Multiple Choice Questions :
Question 1.
Branch of science dealing with the interrelation of a species and its environment is-
(A) Autecology
(B) Synecology
(C) Community biology
(D) Population biology
Answer:
(A) Autecology
Question 2.
Synecology deals with –
(A) A single individual
(B) A population
(C) A community
(D) Different ecosystems
Answer:
(C) A community
Question 3.
At which level of ecology would you explain the event of change in body colour of an animal with the change in intensity of light?
(A) Individual level
(B) Population level
(C) Community level
(D) Ecosystem level
Answer:
(A) Individual level
Question 4.
Synthesis of chlorophyll in green plants is controlled by-
(A) Relative humidity
(B) Atmospheric pressure
(C) Temperature
(D) Light
Answer:
(D) Light
Question 5.
The similarity amongst chlorophyll production, transpiration rate and opening of stomata is that-
(A) All are involved in growth of plants
(B) All are light dependent events
(C) All increase weight of plant body
(D) All decrease weight of plant body
Answer:
(B) All are light dependent events
Question 6.
All the plants and animals together of a particular area are called-
(A) Ecotone
(B) Biome
(C) Biota
(D) Echod
Answer:
(C) Biota
Question 7.
Absorption of water by plants is related to-
(A) Water content of soil
(B) Chlorophyll concentration
(C) Plant height
(D) Starch content of cells
Answer:
(A) Water content of soil
Question 8.
Xerophytes have-
(A) Thick cuticle cover
(B) Less stomata
(C) Thick stem hair
(D) All of these
Answer:
(D) All of these
Question 9.
Zooplanktons come to the surface in day light and go to the bottom at night, this is–
(A) Circadian rhythm
(B) Diurnal rhythm
(C) Photoperiodism
(D) Phototactic movement
Answer:
(A) Circadian rhythm
Question 10.
Heliophytes are adapted to-
(A) Saline soil
(B) Saline water
(C) Bright sunlight
(D) Low sunlight
Answer:
(C) Bright sunlight
Question 11.
Population interaction is discussed under-
(A) Population level
(B) Community level
(C) Ecosystem level
(D) Individual level
Answer:
(B) Community level
Question 12.
Rate of metabolism increases in-
(A) Low temperature
(B) Higher temperature
(C) Low humidity
(D) High CO2
Answer:
(C) Low humidity
Question 13.
A growing population shows-
(A) Low natality
(B) High mortality
(C) Low natality and emigration
(D) Low mortality and immigration
Answer:
(D) Low mortality and immigration
Question 14.
‘S’ shaped growth curve is seen in-
(A) Newly built ant population
(B) Stable human population
(C) Honeybee population
(D) Wasp population
Answer:
(B) Stable human population
Question 15.
High natality and immigration-
(A) Increase population size
(B) Decrease population size
(C) Do not change population size
(D) None of these
Answer:
(A) Increase population size
Question 16.
If B = Birth rate, N = Total number of individuals in a population and nb = Number of live birth, the equation for birth rate will be-
(A) N = nb / B
(B) B = nb / N
(C) B = N*nb
(D) B = N / nb
Answer:
(B) B = nb / N
Question 17.
Size of population remains unchanged if-
(A) Emigration = Immigration
(B) Natality > Mortality
(C) Immigration ≠ Emigration
(D) All of these
Answer:
(A) Emigration = Immigration
Question 18.
Population size decreases with-
(A) Emigration
(B) Immigration
(C) Low mortality
(D) High natality
Answer:
(A) Emigration
Question 19.
A positive inter-specific interaction is-
(A) Mutualism
(B) Parasitism
(C) Predation
(D) Cannibalism
Answer:
(A) Mutualism
Question 20.
Population size does not depend upon-
(A) Migration
(B) Natality
(C) Emigration
(D) Species interaction
Answer:
(D) Species interaction
Question 21.
High rate of predation results in-
(A) Decline in primary consumer
(B) Increase in primary consumer
(C) Decrease in higher level of consumer
(D) Decline in producer
Answer:
(A) Decline in primary consumer
Question 22.
In which of the following interactions, involved members keep very close contact?
(A) Competition
(B) Parasitism
(C) Predation
(D) None of these
Answer:
(B) Parasitism
Question 23.
What is ‘ + +’ interaction?
(A) Autotrophism
(B) Parasitism
(C) Symbiosis
(D) Predation
Answer:
(C) Symbiosis
Question 24.
Which of the following is a topographic factor of ecosystem?
(A) Brightness of light
(B) Wind speed
(C) Slope of hills
(D) Waves of sea
Answer:
(C) Slope of hills
Question 25.
Animals that maintain constant body temperature in any environment are called-
(A) Poikilothermic animals
(B) Homeothermic animals
(C) Eurythermal animals
(D) Stenothermal animals
Answer:
(B) Homeothermic animals
Question 26.
Example of stenothermal animals is-
(A) Birds
(B) Toads
(C) Ants
(D) Fishes
Answer:
(D) Fishes
Question 27.
Which of the following is an example of obligate parasite?
(A) Round worm
(B) Mosquito
(C) Louse
(D) Ticks
Answer:
(A) Round worm
Question 28.
Which of the following is not an abiotic factor?
(A) Water
(B) Soil
(C) Plants
(D) Air
Answer:
(C) Plants
Question 29.
Global ‘sink’ for CO2 is-
(A) Tropical rain forest
(B) Mangrove
(C) Ocean
(D) Coral reef
Answer:
(C) Ocean
Question 30.
Which ecosystem has the highest primary productivity?
(A) Pond
(B) Ocean
(C) Desert
(D) Forest
Answer:
(B) Ocean
Question 31.
The most recently discovered ecosystem is-
(A) Vent*
(B) Crater
(C) Floating iceberg
(D) Coral reef
Answer:
(A) Vent*
Question 32.
Niche of a species is-
(A) Place of living
(B) Specific function
(C) Habitat and specific function
(D) None of these
Answer:
(C) Habitat and specific function
Question 33.
Which one of the following is mismatched?
(A) Deciduous forest : Shorea robusta
(B) Evergreen forest: Pinus roxburghii
(C) Xeric forest : Musa paradisica
(D) Mangrove forest : Barringtonia acutangula
Answer:
(C) Xeric forest : Musa paradisica
Question 34.
Insectivorous plants are-
(A) Organotrophs
(B) Autotrophs
(C) Heterotrophs
(D) Partial heterotrophs
Answer:
(D) Partial heterotrophs
Question 35.
Which of the following levels is not studied in synecology?
(A) Individual level
(B) Population level
(C) Community level
(D) Ecological level
Answer:
(A) Individual level
Question 36.
In ecology, interaction and organization among different organisms is studied in steps.
(A) 2
(B) 3
(C) 4
(D) 5
Answer:
(C) 4
Question 37.
Which of the following is a long day plant?
(A) Pea
(B) Cosmos
(C) Strawberry
(D) Dahlia
Answer:
(A) Pea
Question 38.
Which of the following is a short day plant?
(A) Pea
(B) Dahlia
(C) Clover
(D) Radish
Answer:
(B) Dahlia
Question 39.
Chlorophyll synthesis in plants is regulated by-
(A) Humidity
(B) Wind
(C) Temperature
(D) Light
Answer:
(D) Light
Question 40.
Melanin formation in human skin is regulated by-
(A) Humidity
(B) Light
(C) Temperature
(D) Pressure
Answer:
(B) Light
Question 41.
Migration of salmon, eel fish is regulated by-
(A) Water
(B) Humidity
(C) Temperature
(D) Light
Answer:
(C) Temperature
Question 42.
Temperature affects the size of an organism. This is known as-
(A) Bergmann’s rule
(B) Gloger’s rule
(C) Allen’s rule
(D) Lindeman law
Answer:
(A) Bergmann’s rule
Question 43.
Higher humidity makes the body colour of animals darker. This is known as-
(A) Bergmann’s rule
(B) Gloger’s rule
(C) Allen’s rule
(D) Lindeman law
Answer:
(B) Gloger’s rule
Question 44.
Animals of polar region have smaller pina, tail and limbs. This is known as-
(A) Bergmann’s rule
(B) Gloger’s rule
(C) Allen’s rule
(D) Lindeman law
Answer:
(C) Allen’s rule
Question 45.
The physiological reaction of organisms depending upon the length of day or night, is called-
(A) Photosynthesis
(B) Photoperiodism
(C) Photorespiration
(D) None of these
Answer:
(B) Photoperiodism
Question 46.
The act of leaving one’s native place permanently with the intent to reside somewhere else, is called-
(A) Adaptation
(B) Immigration
(C) Emigration
(D) Extinction
Answer:
(C) Emigration
Question 47.
Example of ‘+0’ interaction is-
(A) Autotrophism
(B) Mutualism
(C) Parasitism
(D) Commensalism
Answer:
(D) Commensalism
Question 48.
All the plant species of an ecosystem is collectively known as –
(A) Flora
(B) Fauna
(C) Biome
(D) Biomass
Answer:
(A) Flora
Question 49.
All the animal species of an ecosystem is collectively known as –
(A) Flora
(B) Fauna
(C) Biome
(D) Biomass
Answer:
(B) Fauna
Question 50.
In an ecosystem, energy flow is always-
(A) Unidirectional
(B) Bidirectional
(C) Tridirectional
(D) Multidirectional
Answer:
(A) Unidirectional
Question 51.
Number of trophic levels in a food chain ranges from-
(A) 14-16
(B) 11-13
(C) 7-10
(D) 3-5
Answer:
(D) 3-5
Question 52.
The percentage (%) of energy that flows to next tropic level in a food chain is-
(A) 100 %
(B) 10 %
(C) 20 %
(D) 90 %
Answer:
(B) 10 %
Question 53.
Lindeman law of energy flow through different trophic levels in an ecosystem is also known as-
(A) 5 % law
(B) 7 % law
(C) 10 % law
(D) 15 % law
Answer:
(C) 10 % law
Question 54.
Which of the following is a grazing food chain?
(A) Organic matter → Earthworm → Bacteria
(B) Plant → Human → Worm
(C) Decaying organic matter → Zooplankton → Small fish → Large fish
(D) Grass → Grasshopper → Frog → Snake → Hawk
Answer:
(D) Grass → Grasshopper → Frog → Snake → Hawk
Question 55.
Actively swimming aquatic organisms in a water body are called-
(A) Necton
(B) Benthos
(C) Plankton
(D) Neuston
Answer:
(A) Necton
Question 56.
Primary source of energy in an ecosystem is-
(A) Water
(B) Soil
(c) Air
(D) Sunlight
Answer:
(D) Sunlight
Question 57.
Food chain was scientifically described in 1966 by scientist-
(A) Tansley
(B) Lindeman
(C) Odum
(D) Haeckel
Answer:
(C) Odum
Question 58.
The community of organisms, that reside on or near the sea-bed is called-
(A) Necton
(B) Plankton
(C) Benthos
(D) Neuston
Answer:
(C) Benthos
Question 59.
The largest consumer population of marine ecosystem belongs to-
(A) Primary consumer
(B) Secondary consumer
(C) Tertiary consumer
(D) Topmost level of consumers
Answer:
(A) Primary consumer
Question 60.
Photoperiodism is a-
(A) Biochemical process
(B) Bio-physical process
(C) Physiological process
(D) All of these
Answer:
(C) Physiological process
Question 61.
Man is-
(A) Autotroph
(B) Omnivorous
(C) Carnivorous
(D) Herbivorous
Answer:
(B) Omnivorous
Question 62.
If different trophic levels are piled one upon another, we shall get-
(A) Food chain
(B) Food web
(C) Food pyramid
(D) Energy pyramid
Answer:
(C) Food pyramid
Question 63.
Which of the following is a component of macronutrient cycle?
(A) Na
(B) Mn
(C) Cu
(D) O2
Answer:
(D) O2
Question 64.
Which of the following is a component of micronutrient cycle?
(A) Cu
(B) C
(C) H2
(D) O2
Answer:
(A) Cu
Question 65.
Inhabitance of Anabaena in the leaf tissue of Azolla is an example of-
(A) Competition
(B) Predation
(C) Symbiosis
(D) Commensalism
Answer:
(C) Symbiosis
Question 66.
In an inter-specific relation, one of the two species is benefited but another one is neither benefited nor harmed. This interaction is called-
(A) Symbiosis
(B) Mutualism
(C) Commensalism
(D) Parasitism
Answer:
(C) Commensalism
Question 67.
Certain bacteria break organic molecules and return elementary components to nature. These bacteria are treated as-
(A) Decomposers
(B) Putrifying bacteria
(C) Transducers
(D) Transformers
Answer:
(D) Transformers
Question 68.
Unit of a population is-
(A) A community
(B) An animal species
(C) A plant species
(D) An individual of a species
Answer:
(D) An individual of a species
Question 69.
Unit of a community is-
(A) An individual of a species
(B) A plant species
(C) An animal species
(D) Population
Answer:
(D) Population
Question 70.
The largest population in an ecosystem is seen amongst-
(A) Decomposers
(B) Producers
(C) Primary consumers
(D) Secondary consumers
Answer:
(B) Producers
Fill in the blanks :
- Group of organisms of same species is known as ______.
- ______ rhythm is the daily rhythm of activities which is controlled by light.
- Animal living in desert regions have few ______ glands.
- Decomposers show ______ nutrition.
- Inflow of bulk of animals into a population is called ______.
- Interaction between flowers and insects is known as ______.
- In predation, the animal which kills other animal to consume it, is called ______.
- The step of food chain is called ______ level.
- Energy flow is ______ -directional.
- Birds of temperate region have ______ wings than that of tropical regions.
- Organisms that break down organic molecules and return elementary components to nature, are called ______.
- There are ______ types of food chain in an ecosystem.
- Carbon cycle is a type of ______ cycle.
- The sum total of the solar energy trapped by all producers is called ______ primary production.
- Cyclical pool of carbon cycle involves the atmosphere and the ______.
Answer:
- Population
- Circadian
- Sweat
- Saprophytic
- Immigration
- Mutualism
- Predator
- Trophic
- Uni Answers
- Narrower
- Transformers
- Three
- Nutrient
- Gross
- Seawater
State true or false :
- Population is a bigger unit than community.
- Light enhances the pigmentation of skin.
- Poikilotherms can maintain constant body temperature.
- Population size remains constant if birth rate is lower than death rate.
- Migration is of two types.
- Lichen is a type of obligatory mutualism.
- Predation normally is an intraspecific interaction.
- Parasitism is a negative-positive association.
- Tapeworm is an ectoparasite.
- Organic matters like protein, fat are biotic factors of an ecosystem.
- Tertiary consumers are considered as decomposers.
- Different food chains interconnect to form food web.
- Only 0.02 % of the total energy, that comes to the earth from the sun, can be trapped.
- Carbon bed of the lithosphere acts as reservoir pool for carbon.
- Chemosynthetic micro-organisms are heterotrophs.
Answer:
- False
- True
- False
- False
- True
- True
- False
- True
- False
- False
- False
- True
- True
- True
- False
Match the columns :
Question 1.
| Left column | Right column |
| 1. Short day plant | A. Rafflesia |
| 2. Long day plant | B. Agaricus, Mucor |
| 3. Day neutral plant | C. Dahlia, sugarcane |
| 4. Heterotrophic plant | D. Pea, radish |
| E. Tomato, cucumber |
Answer:
| Left column | Right column |
| 1. Short day plant | C. Dahlia, sugarcane |
| 2. Long day plant | D. Pea, radish |
| 3. Day neutral plant | E. Tomato, cucumber |
| 4. Heterotrophic plant | A. Rafflesia |
Question 2.
| Left column | Right column |
| 1. Consumer | A. Tapeworm |
| 2. Detritivore | B. Green plant |
| 3. Producer | C. Human |
| 4. Parasite | D. Earthworm |
| E. Decaying leaves |
Answer:
| Left column | Right column |
| 1. Consumer | C. Human |
| 2. Detritivore | D. Earthworm |
| 3. Producer | B. Green plant |
| 4. Parasite | A. Tapeworm |
Question 3.
| Left column | Right column |
| 1. Facultative mutualism | A. Orchid and mango tree |
| 2. Symbiosis | B. Bug and human |
| 3. Commensalism | C. Lichen |
| 4. Predation | D. Insects and flowers |
| E. Tiger and deer |
Answer:
| Left column | Right column |
| 1. Facultative mutualism | D. Insects and flowers |
| 2. Symbiosis | C. Lichen |
| 3. Commensalism | A. Orchid and mango tree |
| 4. Predation | E. Tiger and deer |
Question 4.
| Left column | Right column |
| 1. Transducers | A. Bed bug |
| 2. Ectoparasite | B. Green plants |
| 3. Transformers | C. Plasmodium vivax |
| 4. Endoparasite | D. Bacteria |
| E. Lichen |
Answer:
| Left column | Right column |
| 1. Transducers | B. Green plants |
| 2. Ectoparasite | A. Bed bug |
| 3. Transformers | D. Bacteria |
| 4. Endoparasite | C. Plasmodium vivax |