Civil Services GS Environment Ecology Objective Questions

Civil Service Preliminary Exam GS Environment Ecology MCQ

Consider the following statements and select the correct answer using the code given below:
1. The non-living components set the stage for the operation of the ecosystem.
2. The duration of Sun exposure is the photo-period.
3. Along the equator, days are almost 12 hours in length throughout the year.
Code:

(A) 1 and 2 are correct
(B) 1 and 3 are correct
(C) 2 and 3 are correct
(D) 1, 2 and 3 are correct

Which one of the following statements is not correct?

(A) Operation of the hydrological cycle depends upon precipitation, evaporation and seasonal distribution of rainfall.
(B) The hydrological cycle is an open system.
(C) A plant that grows in water is known as hydrophyte.
(D) A soil that develops in water is known as hydrophyte soil.

Consider the following statements and select the correct answer using the code given below:
1. A cycle at various scales of minerals and compounds through the ecosystem is known as biological cycle.
2. The biochemistry of carbon is of great significance because of the global warming and greenhouse effect.
Code:

(A) Only 1 is correct
(B) Only 2 is correct
(C) Both 1 and 2 are correct
(D) Neither 1 nor 2 is correct.

Which one of the following statements is not correct?

(A) In living matter, hydrogen, oxygen and carbon constitute 99 per cent of the biomass.
(B) Coal mines are the greatest pool of carbon,
(C) The atmosphere is the principal reserve of oxygen;
(D) Large reserves of carbon exist in the earth’s crust.

Consider the following statements and select the correct answer using the code given below:
1. The major reservoirs of water are the oceans and glaciers.
2. The oceans and glaciers contain 97.5 per cent of the world’s water.
3. Less than 1 per cent of the water resides in atmosphere, rivers and lakes and soils.
4. The water vapour can reside in the atmosphere for about 9 days.
Code:

(A) 1,2 and 3 are correct
(B) 1,3 and 4 are correct
(C) 1,2 and 4 are correct
(D) 1, 2, 3 and 4 are correct

Which one of the following statements is not correct?

(A) Phosphorous is abundant in nature.
(B) Phosphates in the soil are taken into plants for protein synthesis,
(C) Phosphates pass through the food chain,
(D) Guano droppings are used as fertilizers.

Which one of the following is not correct?

(A) The application of chemical fertilizers in modern agriculture damage the phosphorous cycle.
(B) The application of chemical fertilizers make the soils sustainable.
(C) Application of chemical fertilizers change the soil chemistry.
(D) Erosion and weathering are more serious in the soils in which heavy doses of chemical fertilizers is use

Consider the following statements and select the correct answer using the code given below:
1. Ecological succession occurs when older communities of plants and animals are replaced by new communities.
2. In ecological succession, the new communities are usually more simple.
Code:

(A) 1 and 2 are correct
(B) Only 1 is correct
(C) Only 2 is correct
(D) Neither 1 nor 2 is correct

Which one of the following is not correct?

(A) The process whereby different and usually more complex assemblages of plants and animals replace older and usually simpler communities is called ecological succession.
(B) Ecosphere is another name for the biosphere.
(C) The role that an organism takes in the ecosystem is known as ecological niche.
(D) Ecological succession does not need an initiating disturbance.

Consider the following statements and select the correct answer using the code given below:
1. A bare rock can be a site for primary succession.
2. The initial community is called as a pioneer community.
3. Secondary succession begins on an abandoned farm of formerly ploughed field.
Code:

(A) 1 and 2 are correct
(B) 1 and 3 are correct
(C) 2 and 3 are correct
(D) 1, 2 and 3 are correct

Consider the following statements and select the correct answer using the code given below:
1. In ecology, fire is recognized as an ingredient of community succession.
2. Controlled fire secures plant reproduction and prevents accumulation of forest litter.
Code:

(A) Only 1 is correct
(B) Only 2 is correct
(C) Both 1 and 2 are correct
(D) Neither 1 nor 2 is correct

Which one of the following is not correct?

(A) At present, fire is recognized as a natural component of most ecosystems.
(B) In many forests, undergrowth is burned in controlled cool fire.
(C) When forests are not burned, they lead to abundant undergrowth Accumulation,
(D) The undergrowth accumulation of litter is conducive for the sustainability of the ecosystem.

Consider the following statements and select the correct answer using the code given below:
1. Food chain is the sequence of transfer of energy from the lower levels to the upper or higher trophic level.
2. Food chain is the way an organism obtains physical, chemical and biological factors it needs to survive.

(A) 1 and 2 are correct
(B) Only 1 is correct
(C) Only 2 is correct
(D) Neither 1 nor 2 is correct

Consider the following statements and select the correct answer using the code given below:
1. Lakes and ponds also exhibit ecological succession.
2. A lake may be filled with nutrients and sediments, and as an aquatic plant takes root and grows, it captures more sediment and adds organic debris to the system.
3. The gradual enrichment of water bodies is known as Eutrophication.
Code:

(A) 1 and 2 are correct
(B) 1 and 3 are correct
(C) 2 and 3 are correct
(D) 1,2 and 3 are correct

Consider the following statements and select the correct answer using the code given below:
1. Basically, all animals depend on plants for their food.
2. Rabbits eat grasses and foxes may eat rabbit.
3. A hawk eats a lizard; the lizard had just eaten a grasshopper.
4. The food-web is similar in all the tropical countries.
Code:

(A) 1,2 and 3 are correct
(B) 1,3 and 4 are correct
(C) 1,2 and 4 are correct
(D) 1, 2 3 and 4 are correct