2021 Prelims Paper 1 UPSC Question Paper

2021 Prelims Paper 1 UPSC Questions

11.

The vegetation of savannah consists of grassland with scattered small trees, but extensive areas have no trees. The forest development in such areas is generally kept in check by one or more or a combination of some conditions. Which of the following are such conditions?
1. Burrowing animals and termites
2. Fire
3. Grazing herbivores
4. Seasonal rainfall
5. Soil properties
Select the correct answer using the code given below.

A.

1 and 2

B.

4 and 5

C.

2, 3 and 4

D.

1, 3 and 5

ANSWER :

C. 2, 3 and 4

12.

With reference to the water on the planet Earth, consider the following statements:
1. The amount of water in the rivers and lakes is more than the amount of groundwater.
2. The amount of water in polar ice caps and glaciers is more than the amount of groundwater.
Which of the statements given above is/are correct?

A.

1 only

B.

2 only

C.

Both 1 and 2

D.

Neither 1 nor 2

ANSWER :

B. 2 only

13.

Consider the following statements:
1. Moringa (drumstick tree) is a leguminous evergreen tree.
2. The tamarind tree is endemic to South Asia.
3. In India, most of the tamarind is collected as minor forest produce.
4. India exports tamarind and seeds of moringa.
5. Seeds of moringa and tamarind can be used in the production of biofuels.
Which of the statements given above are correct?

A.

1, 2, 4 and 5

B.

3, 4 and 5

C.

1, 3 and 4

D.

1, 2, 3 and 5

ANSWER :

B. 3, 4 and 5

14.
The black cotton soil of India has been formed due to the weathering of
A.
brown forest soil
B.
fissure volcanic rock
C.
granite and schist
D.
shale and limestone
ANSWER :
B. fissure volcanic rock
15.

With reference to recent developments regarding ‘Recombinant Vector Vaccines’, consider the following statements:
1. Genetic engineering is applied in the development of these vaccines.
2. Bacteria and viruses are used as vectors.
Which of the statements given above is/are correct?

A.

1 only

B.

2 only

C.

Both 1 and 2

D.

Neither 1 nor 2

ANSWER :

C. Both 1 and 2

16.

In the context of hereditary diseases, consider the following statements:
1. Passing on mitochondrial diseases from parent to child can be prevented by mitochondrial replacement therapy either before or after in vitro fertilization of the egg.
2. A child inherits mitochondrial diseases entirely from the mother and not from the father.
Which of the statements given above is/are correct?

A.

1 only

B.

2 only

C.

Both 1 and 2

D.

Neither 1 nor 2

ANSWER :

A. 1 only

17.
Bollgard I and Bollgard II technologies are mentioned in the context of
A.
clonal propagation of crop plants
B.
developing genetically modified crop plants
C.
production of plant growth substances
D.
production of biofertilizers
ANSWER :
B. developing genetically modified crop plants
18.

In a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following?
1. Area of the hole in the lid
2. Temperature of the flame
3. Weight of the lid
Select the correct answer using the code given below.

A.

1 and 2 only

B.

2 and 3 only

C.

1 and 3 only

D.

1, 2 and 3

ANSWER :

C. 1 and 3 only

19.

Consider the following:
1. Bacteria
2. Fungi
3. Virus
Which of the above can be cultured in an artificial/synthetic medium?

A.

1 and 2 only

B.

2 and 3 only

C.

1 and 3 only

D.

1, 2 and 3

ANSWER :

A. 1 and 2 only

20.

Consider the following statements:
1. Adenoviruses have single-stranded DNA genomes whereas retroviruses have double-stranded DNA genomes.
2. Common cold is sometimes caused by an adenovirus whereas AIDS is caused by a retrovirus.
Which of the statements given above is/are correct?

A.

1 only

B.

2 only

C.

Both 1 and 2

D.

Neither 1 nor 2

ANSWER :

B. 2 only