Environmental Studies · Biology

Ecology and Biodiversity

1,739 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 zoology meaning of life energy flow and loss energy flow in a food chain energy flows

The pyramid of number of individuals per unit area in grassland ecosystem will be

  1. Erect

  2. Inverted

  3. Both A and B

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

Pyramids of numbers describes the relationship between organisms at successive trophic levels in terms of their number. In grassland, the producers, which are mainly grasses are always maximum in number as compared to the  primary consumers, the secondary consumers like snakes and lizards are lesser in number than the rabbits and mice. Finally, the top (tertiary) consumers like hawks or other birds are least in number. Thus, the pyramid becomes upright.

Therefore, the correct answer is option A.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

A component of physical environment of an ecosystem is

  1. Sunlight

  2. Decomposers

  3. Water

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

The physical components of the environment are also known as abiotic components. They include soil, water, air, climate, temperature and sunlight. It determines the type of habitat or living conditions of the living population. Thus the correct answer is option A.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

The importance of ecosystem lies in

  1. Cycling of materials

  2. Flow of energy

  3. Both A and B

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

The ecosystem is an interaction between living beings (biotic component) and their physical environment (abiotic component).

The most important characteristics of any ecosystem are energy flow and cycling of materials. Green plants trap solar energy and convert it into a usable form, which is passed on to successive levels through food chains and food webs. The other important characteristic of the ecosystem is cycling of materials. This is called as the biogeochemical cycle, in which decomposers release nutrients back to the environment to maintain the ecosystem. Thus, the correct answer is option C.

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

In terrestrial ecosystem, maximum energy is present in

  1. $T _3$
  2. $T _2$
  3. $T _1$
  4. $T _4$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The first trophic level is represented as T$ _1$. It includes producers. The second trophic level is represented as T$ _2$. It includes primary consumers. Similarly, third trophic level is represented as T$ _3$. It includes secondary consumers. In terrestrial ecosystem, maximum energy is present in T$ _1$, that is producers.

Thus, the correct answer is 'T$ _1$.' 

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

In an ecosystem, which of the following shows one-way passage?

  1. Free energy

  2. Carbon

  3. Nitrogen

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

Energy flow is the amount of energy that flows from one trophic level to another trophic level in an ecosystem. It is unidirectional or one-way passage. In an ecosystem, flow of free energy occurs through different trophic levels. Producers or plants obtain their energy from the sun by photosynthesis. The primary consumers (herbivores) obtain their energy from the producers. The secondary consumers (carnivores) obtained their energy by using herbivores as a source of food and so on. The energy present at each successive trophic level is 10% of the previous trophic level.

Thus, the correct answer is 'Free energy.'

Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

Ecosystem is not accepted by which law of thermodynamics ? 

  1. 1 st law

  2. Zeroth law

  3. 2 nd law

  4. 3rd law
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

First law of thermodynamics defines that the energy neither created nor destroyed but can only be transformed. Ecosystem is not accepted by the 1st law of thermodynamics because the energy is created.

So, the correct option is '1 st law'.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Which of the following statements regarding the estimates of number of species found on earth is not correct?

  1. Total number of species present on earth are considered to be about 7 million as estimated by Robert May.

  2. Plants constitute more than 70% of all the species recorded, whereas animals constitute less than 22% of the total number of species.

  3. Insects constitute more than 70% of all the animal species.

  4. None of these.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Animals constitute more than 70% of all the species recorded whereas plants constitute around 22% of total number of species. 

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Species diversity ______ as one moves from high to low altitudes.

  1. increases

  2. decreases

  3. first increases then decreases

  4. first decreases then increases
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Biodiversity changes with the change in altitude. It increases as one moves from higher to lower altitudes.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

On a logarithmic scale, the species area relationship is a straight line described by the equation log S = log C + Z log A.
What does S, C, Z and A represent in the given equation? Select the correct answer from the codes given below.
Species richness = 1
Slope of the line  = 2
Y- intercept          = 3 
Area                    = 4

  1. 1 - C; 2 - S; 3 - Z; 4 - A

  2. 1 - S; 2 - Z; 3 - C; 4 - A

  3. 1 - Z; 2 - S; 3 - C; 4 - A

  4. 1 - A; 2 - C; 3 - S; 4 - Z
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The relationshipbetween species richness and area is rectangular hyperbola for a wide variety of taxa whether they are birds, bats, freshwater fishes or flowering plants and the equation can be given as S = $CA^z$.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

The term $\alpha$ - diversity refers to

  1. Genetic diversity

  2. Community and ecosystem diversity

  3. Diversity among the plants

  4. Species diversity
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The local species pool is known as alpha diversity. It is also the diversity present within the community. The term was introduced by R. H. Whittaker. Example of such diversity includes high tree diversity throughout the Amazon Rainforests of Ecuador. Generally, gamma diversity = alpha diversity x beta diversity.

So, the correct answer is 'Species diversity'.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Which of the following represents the biodiversity of an area?

  1. Gene

  2. Species

  3. Ecosystem

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

In our biosphere immense diversity (or heterogeneity), exists not only at the species level but at all levels of biological organisation ranging from macromolecules within cells to biomes. Biodiversity is the term popularised by the sociobiologist Edward Wilson to describe the combined diversity at all the levels of biological organisation. The most important of them are- 
(i) Genetic diversity.
(ii) Species diversity.
(iii) Ecological diversity.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Which of the following statements is correct?

  1. Species diversity, in general, increases from poles to the equator

  2. Conventional taxonomic methods are equally suitable for higher plants and microorganisms

  3. Indias share of global species diversity is about 18%

  4. There are about 25000 species of plants in India
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
In general, species diversity, in general, increases from poles to the equator. With very few exceptions, tropics (latitudinal range of 23.5° N to 23.5° S) harbor more species than temperate or polar areas. The reason is that tropical environments, unlike temperate ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialization and lead to greater species diversity.
So, the correct answer is 'Species diversity, in general, increases from poles to the equator'.
Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Regional diversity is also called

  1. Alpha diversity

  2. Beta diversity

  3. Gamma diversity

  4. Ecosystem diversity
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Alpha diversity refers to the average species diversity of a habitat. Beta diversity is the diversity species between two habitats or regions and is given by the ratio between local (alpha species diversity) and regional species diversity. It is also known as the regional species diversity. Gamma diversity is the total diversity of a landscape.
So, the correct option is 'Beta diversity'.