NEET Biology Ecosystem MCQs Set E

Question: Secondary productivity is rate of formation of new organic matter by

• a) Consumer
• b) Decomposer
• c) Producer
• d) Parasite

Answer: Consumer

Question: Which one of the following processes during decomposition is correctly described?

• a) Fragmentation-Carried out by organisms such as earthworm
• b) Leaching-Water soluble inorganic nutrients rise to the top layers of soil
• c) Catabolism-Last step in the decomposition under fully anaerobic condition
• d) Humification-Leads to the accumulation of a dark coloured substance humus which undergoes microbial action at a very fast rate

Answer: Fragmentation-Carried out by organisms such as earthworm

Question: Which one of the following is not a functional unit of an ecosystem?

• a) Stratification
• b) Energy flow
• c) Decomposition
• d) Productivity

Answer: Stratification

Question: The upright pyramid of number is absent in

• a) Forest
• b) Pond
• c) Grassland
• d) Lake

Answer: Forest

Question: Which one of the following is not a gaseous biogeochemical cycle in ecosystem?

• a) Phosphorus cycle
• b) Sulphur cycle
• c) Carbon cycle
• d) Nitrogen cycle

Answer:  Phosphorus cycle

Question: Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels ?

• a) Level PC is "insects" and level SC is "small insectivorous birds"
• b) Level PP is "phytoplanktons" in sea and "Whale" on top level TC
• c) Level PC is "rates" and level SC is "cats"
• d) Level one PP is "pipal trees" and the level SC is "sheep

Answer: Level PC is "insects" and level SC is "small insectivorous birds"

Question:

• a) Cobra
• b) Parrot
• c) Rabbit
• d) Wolf

Answer: Cobra

Question: The rate of formation of new organic matter by rabbit in a grassland, is called

• a) Secondary productivity
• b) Gross primary productivity
• c) Net productivity
• d) Net primary productivity

Answer:  Secondary productivity

Question: The second stage of hydrosere is occupied by plants like

• a) Vallisneria
• b) Salix
• c) Typha
• d) Azolla

Answer: Vallisneria

Question:

• a)

  

  

• b)

  

  

• c)

  

  

• d) None of these

Answer:

Question: Mass of living matter at a trophic level in an area at any time is called

• a) Standing crop
• b) Detritus
• c) Humus
• d) Standing state

Answer: Standing crop

Question: Which one of the following statements is correct for secondary succession?

• a) It occurs on a deforested site
• b) It follows primary succession
• c) It begins on a bare rock
• d) It is similar to primary succession except that it has a relatively fast pace

Answer: It occurs on a deforested site

Question: Which one of the following statements for pyramid of energy is incorrect, whereas the remaining three are correct?

• a) It is inverted in shape
• b) It shows energy content of different trophic level organisms
• c) Its base is broad
• d) It is upright in shape

Answer: It is inverted in shape

Question: Which one of the following animals may occupy more than one trophic levels in the same ecosystem at the same time?

• a) Sparrow
• b) Lion
• c) Frog
• d) Goat

Answer: Sparrow

Question: Both, hydrarch and xerarch successions lead to

• a) Medium water conditions
• b) Highly dry conditions
• c) Excessive wet conditions
• d) Xeric conditions

Answer: Medium water conditions

Question: Of the total incident solar radiation the proportion of PAR is

• a) Less than 50%
• b) About 60%
• c) About 70%
• d) More than 80%

Answer: Less than 50%

Question: The breakdown of detritus into smaller particles by earthworm is a process called

• a) Fragmentation
• b) Humification
• c) Catabolism
• d) Mineralisation

Answer: Fragmentation

Question: The biomass available for consumption by the herbivores and the decomposers is called

• a) Net primary productivity
• b) Standing crop
• c) Gross primary productivity
• d) Secondary productivity

Answer: Net primary productivity

Question:

• a) C
• b) B
• c) A
• d) D

Answer: C

Question:  The correct sequence of plants in a hydrosere is

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which one of the following types of organisms occupy more than one trophic level in a pond ecosystem ?

• a) Fish
• b) Zooplankton
• c) Frog
• d) Phytoplankton

Answer: Fish

Question: About 70% of total global carbon is found in

• a) Oceans
• b) Agroecosystems
• c) Grasslands
• d) Forests

Answer: Oceans

Question:  Consider the following statements concerning food chains

(a) Removal of 80% tigers from an area resulted in greatly increased growth of vegetation.
(b) Removal of most of the carnivores resulted in an increased population of deers.
(c) The length of food chains is generally limited to 3-4 trophic levels due to energy loss.
(d) The length of food chains may vary from 2 to 8 trophic levels.
Which two of the above statements are correct?

• a) b & c
• b) c & d
• c) a & d
• d) a & b

Answer: b & c

Question: The slow rate of decomposition of fallen logs in nature is due to their

• a) Low moisture content
• b) Anaerobic environment around them
• c) Low cellulose content
• d) Poor nitrogen content

Answer: Low moisture content

Question: Which one of the following ecosystem types has the highest annual net primary productivity?

• a) Tropical rain forest
• b) Temperate evergreen forest
• c) Temperate deciduous forest
• d) Tropical deciduous forest

Answer: Tropical rain forest

Question: Which one of the following is not used for construction of ecological pyramids?

• a) Fresh weight
• b) Number of individuals
• c) Dry weight
• d) Rate of energy flow

Answer: Fresh weight

Question: Which of the following groups is absolutely essential functional component of the ecosystem

• a) Producers and detritivores
• b) Producers
• c) Producers and herbivores
• d) Detritivores

Answer: Producers and detritivores

Question: Which of the following ecosystem has the highest gross primary productivity?

• a) Rain forest
• b) Grassland
• c) Coral reef
• d) Mangroves

Answer:  Rain forest

Question: The rate at which light energy is converted into chemical energy of organic molecules is the ecosystem’s

• a) Gross primary productivity
• b) Gross secondary productivity
• c) Net secondary productivity
• d) Net primary productivity

Answer: Gross primary productivity

Question: Which of the following is expected to have the highest value (gm/m²/yr) in a grassland ecosystem?

• a) Gross production (GP)
• b) Secondary production
• c) Tertiary production
• d) Net production (NP)

Answer: Gross production (GP)

Question: An ecosystem which can be easily damaged but can recover after some time if damaging effect stops will be having

• a) Low stability and high resilience
• b) Low stability and low resilience
• c) High stability and low resilience
• d) High stability and high resilience

Answer: Low stability and high resilience

Question: Which one of the following is a primary consumer in maize field ecosystem?

• a) Grasshopper
• b) Wolf
• c) Phytoplankton
• d) Phytoplankton

Answer: Grasshopper

Question: When man eats fish which feeds on zooplankton which have eaten small plants, the producer in the chain is

• a) Small plants
• b) Fish
• c) Man
• d) Zooplankton

Answer: Small plants

Question: The dominant second trophic level, in a lake ecosystem, is

• a) Zooplanktons
• b) Submerged rooted vegetation
• c) Phytoplanktons
• d) Benthos

Answer: Zooplanktons

Question: If we completely remove the decomposers from an ecosystem, its functioning will be adversely affected, because

• a) Mineral movement will be blocked
• b) Energy flow will be blocked
• c) The rate of decomposition will be very high
• d) Herbivores will not receive solar energy

Answer: Mineral movement will be blocked

Question: In a biotic community, the primary consumers are

• a) Herbivores
• b) Carnivores
• c) Omnivores
• d) Detritivores

Answer: Herbivores

Question: The 10% energy transfer law of food chain was given by

• a) Lindemann
• b) Tansley
• c) Stanley
• d) Weismann

Answer: Lindemann

Question: Which of the following acts as “nature’s scavengers”?

• a) Microorganisms
• b) Man
• c) Animals
• d)  Insects

Answer: Microorganisms

Question: In desert grasslands, which type of animals are relatively more abundant?

• a) Fossorial
• b) Diurnal
• c) Arboreal
• d) Aquatic

Answer: Fossorial

Question: In a terrestrial ecosystem such as forest, maximum energy is available at which trophic level?

• a) T₁
• b) T₂
• c) T₃
• d) T₄

Answer: T₁

Question: Energy transfer from one trophic level to other, in a food chain, is

• a) 10%
• b) 20%
• c) 1%
• d) 2%

Answer: 10%

Question: Which of these is responsible for highest biomass in aquatic ecosystem?

• a) Benthoic and brown algae
• b) Nanoplankton, blue green algae, green algae
• c) Sea grass, and slime moulds
• d) Diatoms

Answer: Benthoic and brown algae

Question:  Plant decomposers are

• a) Monera and fungi
• b) Protista and animalia
• c) Fungi and plants
• d) Animalia and monera

Answer: Monera and fungi

Question: Bamboo plant is growing in a fir forest then what will be the trophic level of it?

• a) First trophic leve
• b) Second trophic level
• c) Third trophic level
• d) Fourth trophic level

Answer: First trophic leve

Question: Which of the following is the most stable ecosystem?

• a) Ocean
• b) Forest
• c) Desert
• d) Mountain

Answer: Ocean

Question: The primary succession refers to the development of communities on a

• a) Newly-exposed habitat with no record of earlier vegetation
• b) Forest clearing after devastaing fire
• c) Freshly cleared crop field
• d) Pond, freshly filled with water after a dry phase

Answer: Newly-exposed habitat with no record of earlier vegetation

Question: Which one of the following is not a gaseous biogeochemical cycle in ecosystem?

• a) Phosphorus cycle
• b) Sulphur cycle
• c) Carbon cycle
• d) Nitrogen cycle

Answer: Phosphorus cycle

Question: Which of the following pairs is a sedimentary type of biogeochemical cycle?

• a) Phosphorus and sulphur
• b) Phosphorus and carbon
• c) Phosphorus and nitrogen
• d) Oxygen and nitrogen

Answer: Phosphorus and sulphur

Question: The main role of bacteria in the carbon cycle involves

• a) Digestion or breakdown of organic compounds
• b) Assimilation of nitrogenous compounds
• c) Chemosynthesis
• d) Photosynthesis

Answer: Digestion or breakdown of organic compounds

Question: Earth is a/an

• a) Both
• b) Closed system
• c) Open system
• d) None of these

Answer: Both