Environmental Studies · Biology

Ecology and Biodiversity

1,737 Questions

Ecology and biodiversity are vital topics in environmental studies, covering ecosystem structures, species diversity, and environmental impacts. These concepts are frequently tested in competitive examinations for civil services and state selections. The questions cover carrying capacity, ecological succession, and conservation fundamentals.

Species richness measurementTypes of ecological diversityBiome distribution factorsCarrying capacity conceptEcosystem servicesEnvironmental Impact Assessment

Ecology and Biodiversity Questions

Multiple choice evs earth - our home need to conserve biodiversity protecting our environment rules are for everyone

What is a keystone species?

  1. A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organization and survival.

  2. A common species that has plenty of biomass, yet has a fairly low impact on the community's organization.

  3. A rare species that has minimal impact on the biomass and on other species in the community.

  4. A dominant species that constitutes a large proportion of the biomass and which affects many other species.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A keystone species is often a dominant predator whose removal allows a prey population to explode and often decreases overall diversity. Other kinds of keystone species are those, such as coral or beavers, that significantly alter the habitat around them and thus affect large numbers of other organisms.

Multiple choice evs earth - our home need to conserve biodiversity protecting our environment rules are for everyone

A biosphere reserve conserves and preserves

  1. Wild animals

  2. Land

  3. Natural vegetation

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An area which is conserved to protect the biodiversity and culture of that area is known as biosphere reserve. A biosphere reserve is consisted of many protected areas like sanctuaries, national parks, lakes, lands mountains etc. 

Multiple choice evs earth - our home need to conserve biodiversity protecting our environment rules are for everyone

All non-domesticated and non-cultivated biota in the natural environment are termed 

  1. Wildlife

  2. Ordinary life

  3. Domesticated life

  4. Stray life
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
 The term biota refers to a group of animals, plants or other organisms that share the same geographical region. All non domesticated and non cultivated biota in natural environment are called wild life. E.g. Lion, deer etc and plants like sunflower, thyme present in the natural environment.
So, the correct answer is 'Wildlife'
Multiple choice evs earth - our home need to conserve biodiversity protecting our environment rules are for everyone

The species though insignificant in number; determine the existence of many other species in a given ecosystem. Such species is known as

  1. Extinct species

  2. Keystone species

  3. Endemic species

  4. Sacred species
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A keystone species is a species that has a disproportionately large effect on its environment relative to its abundance. Such species are described as playing a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and numbers of various other species in the community. 

Extinction is the end of an organism or of a group of organisms (taxon), normally a species.
Endemic species is one that is only found in that region and nowhere else in the world. They are of conservation concern because they are not widespread and may be confined to only one or two protected areas. 
Certain life forms, often a keystone species, are sacred to indigenous peoples because they present a body of knowledge and ways leading to balanced relationship with life.

Multiple choice zoology biodiversity and conservation hotspots and methods of conservation biodiversity: conservation conservation of biodiversity basis of classification in animals basis of the classification of animals criteria for animal classification five kingdoms of living organisms biodiversity and need of classification biodiversity and classification

Vertical distribution of different species occupying different levels in dense vegetation is called.

  1. Stratification

  2. Species composition

  3. Standing crop

  4. Trophic structure
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Vertical distribution of different species occupying different levels is called stratification. For example, trees occupy top vertical strata or layer of a forest, strubs the second and herbs and grasses occupy the bottom layers.

Multiple choice zoology biodiversity and conservation hotspots and methods of conservation biodiversity: conservation conservation of biodiversity basis of classification in animals basis of the classification of animals criteria for animal classification five kingdoms of living organisms biodiversity and need of classification biodiversity and classification

Ecological amplitude of a species is related to

  1. Zones of stress

  2. Zone of optimum tolerance range of a factor

  3. Area with zones of optimum tolerance ranges of all determining factors

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ecological amplitude refers to the range of environmental conditions (tolerance) under which a species can survive and reproduce successfully.

Multiple choice botany ecosystem energy flow in food chain food chain and energy flow energy flow in ecosystem

Ecological efficiency is

  1. $\frac{Food\ energy\ assimilated}{Food\ energy\ ingested}$ x 100
  2. $\frac{Gross\ primary\ productivity}{Incident\ total\ solar\ radiation}$ x 100
  3. $\frac{Volume\ of\ CO _2\ evolved}{Volume\ of\ O _2\ consumed}$
  4. $\frac{Energy\ in\ biomass\ production\ at\ a\ trophic\ level}{Energy\ in\ biomass\ production\ at\ previous\ trophic\ level}$ x 100
  5. $\frac{Net\ primary\ productivity}{Gross\ primary\ productivity}$ x 100
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An ecological efficiency is the efficiency of energy transfer from one trophic level to the next trophic level. In other words, it is the energy in biomass production at a trophic level divided by energy in biomass production at previous trophic level. It is the ratio of energy flows at different trophic levels in a food-chain. It is expressed in percentage.

Thus, the correct answer is 'Energy in biomass production at a trophic level / Energy in biomass production at previous trophic level x 100.'

Multiple choice economics environmental economics acid rain air pollution - effects and control air pollution and its effects

Acid rain is produced when rain mixes with gases such as sulphur dioxide. This will eventually result in

  1. Lowering of pH and changes of temperature in ponds

  2. Raising of pH in ponds, encouraging growth of if microorganisms

  3. Lowering of pH in ponds, limiting survival of aquatic organisms

  4. Raising of pH in ponds, limiting development of organisms
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The ecological effects of acid rain are most clearly seen in the aquatic environments, such as streams, lakes, etc. Acid rain flows into streams, lakes and marshes after falling on forests, fields, building and roads. Acid rain water primarily decreases the pH of water sources from normal range (6 to 8 pH) Lakes and streams become acidic (i.e., pH values goes down), when water itself and its surrounding soil cannot buffer the acid rain water to neutralize it. In areas where buffering capacity is low, acid rain releases aluminium from soils into lakes and streams, aluminium is highly toxic to many species of aquatic organisms leading to their mortality. Therefore, limiting the survival of aquatic animals. So, the correct answer is 'Lowering of pH in ponds, limiting survival of aquatic organisms'.

Multiple choice economics environmental economics acid rain air pollution - effects and control air pollution and its effects

Read the passage and answer the following questions:
Acid rain is formed after the burning of fossil fuels releases compounds containing nitrogen and sulfur into the atmosphere. Sunlight and rain bring about chemical reactions that convert these compounds into nitric acid and sulfur dioxide, which combine with water droplets to form acid rain. Acid rain typically has a pH of approximately 5.5. "The higher acidity of soil and water affects many living organisms adversely. As the pH of lake water falls, fish become ill and die. Table 1 shows the effects of pH on the size of adult fish.

pH of lake Average length of fish (cm)    Average mass of fish (g)
7.5 30 cm 454 g
7.0 28 cm    450 g
6.5 29 cm  453 g
6.0 25 cm   401 g
5.5 20 cm    288 g
5.0 17 cm 127 g
4.5 All fish died All fish died


Mycorrhizal fungi, which form a mutualistic association with many plant roots, are particularly sensitive to the effects of acid rain. These fungi facilitate the
absorption of water and nutrients by the plants; in turn, the plants provide sugars and amino acids without which the fungi could not survive.
Fungi are classified as

  1. Prokaryotic decomposers

  2. Eukaryotic producers

  3. Eukaryotic decomposers

  4. Eukaryotic autotrophs

  5. Prokaryotic consumers
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fungi have a well-defined nucleus and membrane-bound organelles and are classified as eukaryotes.

Fungi are not producers (can not synthesize organic compounds by themselves), they feed on the dead and decaying matter and derive their nutrition by decomposition of complex organic matter present in debris making them saprophytes and decomposers. 
Therefore, the correct answer is option C.

Multiple choice economics environmental economics acid rain air pollution - effects and control air pollution and its effects

Acid rain is produced when rain mixes with chemicals such as sulfur dioxide in the air. This may result in

  1. Lowering the pH in ponds, thus limiting the survival of many organisms

  2. Lowering the pH in ponds, thus affecting water temperature

  3. Raising the pH in ponds, thus encouraging the growth of organisms

  4. Raising the pH in ponds, thus limiting animal development

  5. Depleting atmospheric carbon dioxide available for photosynthesis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Acid rain will lower down the pH of pond water and will cause an adverse effect on survival of many organisms as the acidic environment does not support the growth and existence of organisms. 

Normal pond water has neutral or slightly alkaline pH; acid rain would lower down its pH. 
Water temperature of the pond is determined by the availability of Sunlight and depth of water. 
pH does not affect the level of available dissolved carbon dioxide. 
Therefore, the correct answer is option A.

Multiple choice economics environmental economics acid rain air pollution - effects and control air pollution and its effects

Read the passage and answer the following questions.


Acid rain is formed after the burning of fossil fuels releases compounds containing nitrogen and sulphur into the atmosphere. Sunlight and rain bring about chemical reactions that convert these compounds into nitric acid and sulphur dioxide, which combine with water droplets to form acid rain. Acid rain typically has a pH of approximately 5.5. "The higher acidity of soil and water affects many living organisms adversely. As the pH of lake water falls, fish become ill and die. Table 1 shows the effects of pH on the size of adult fish.

pH of lake Average length of fish (cm)    Average mass of fish (g)
7.5 30 cm    454 g
7.0 28 cm  450 g
6.5 29 cm   453 g
6.0 25 cm    401 g
5.5 20 cm    288 g
5.0 17 cm   127 g
4.5 all fish died all fish died


Mycorrhizal fungi, which form a mutualistic association with many plant roots, are particularly sensitive to the effects of acid rain. These fungi facilitate the absorption of water and nutrients by the plants; in turn, the plants provide sugars and amino acids without which the fungi could not survive.
What might be the best strategy to prevent the death of the fishes?

  1. Stock the lakes with bigger fish so that they can resist the effects of the acid better

  2. Reduce the amount of fossil fuels that are burned

  3. Supply plants with excess phosphorus and water

  4. Supply fungi with excess sugars and amino acids

  5. Add alkalines to soil and water to neutralize the acid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Acid rain is caused by burning of fossil fuels. By reducing the amount of burning of fossil fuel, which is one of the major cause of acid rain, frequency of acid rain can be reduced. Bigger fishes may or may not withstand the acidity. Supply of excess phosphorus and water may not benefit the plants as absorption of these substances by plant is not guaranteed. Likewise, supplying excess sugar and amino acid wont benefit the fungi. Adding alkaline might help but are not eco-friendly.

Therefore, the correct answer is option B.

Multiple choice economics environmental economics acid rain air pollution - effects and control air pollution and its effects

Read the passage and answer the following questions.


Acid rain is formed after the burning of fossil fuels releases compounds containing nitrogen and sulphur into the atmosphere. Sunlight and rain bring about chemical reactions that convert these compounds into nitric acid and sulphur dioxide, which combine with water droplets to form acid rain. Acid rain typically has a pH of approximately 5.5." . The higher acidity of soil and water affects many living organisms adversely. As the pH of lake waterfalls, fish become ill and die. Table 1 shows the effects of pH on the size of adult fish.

pH of lake Average length of fish (cm)    Average mass of fish (g)
7.5 30 cm 454 g
7.0 28 cm 450 g
6.5 29 cm  453 g
6.0 25 cm    401 g
5.5 20 cm    288 g
5.0 17 cm    127 g
4.5 all fish died all fish died


Mycorrhizal fungi, which form a mutualistic association with many plant roots, are particularly sensitive to the effects of acid rain. These fungi facilitate the absorption of water and nutrients by the plants; in turn, the plants provide sugars and amino acids without which the fungi could not survive.
If the pH of the soil was 7.0, then

  1. The fungi would survive but the plant would be harmed.

  2. The fungi would be harmed but the plant would survive.

  3. The fungi would be slightly harmed and the plant would be slightly harmed.

  4. Both the fungi and plant would survive.

  5. Neither the fungi nor the plant would be harmed.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

pH 7 is the neutral pH that does not harm plants and animals. Both plant and fungi will survive. Thus, the correct answer is option D.