Previous year MCQs

General science UPPSC 2023 GS-I
Question

Which among the following is a constituent of natural silk?

Answer & Solution

Answer: (Detailed Solution Below)

Option B: Nitrogen

Detailed Solution:

The correct answer is “Nitrogen”.
Natural silk is primarily made of proteins, and proteins are composed of amino acids, which contain nitrogen. The primary protein in silk is fibroin, which is rich in nitrogen as part of its amino acid composition.
The other elements listed—phosphorus, magnesium, and potassium—are not the primary constituents of silk fibers.

Similar Questions:

Which of the following has the largest brain in proportion to its body size?
  1. A) Ant
  2. B) Elephant
  3. C) Dolphin
  4. D) Human Being
The energy of the sun is produced by?
  1. A) Ionisation
  2. B) Nuclear fusion
  3. C) Nuclear fission
  4. D) Oxidation
Which one of the following compounds is used as a sedative?
  1. A) Potassium bromide
  2. B) Calcium chloride
  3. C) Ethyl alcohol
  4. D) Phosphorus trichloride
Given below are two statements, one is labelled as Assertion (A) and the other as Reason (R).

Assertion (A): CO2, SO2 and NO2 gases get dissolved in rain water and produce acid rain.
Reason (R): Atmospheric air is polluted due to high concentration of gases like carbon dioxide, sulphur dioxide and oxides of nitrogen.

Select the correct answer from the codes given below:
  1. A) Both (A) and (R) are true and (R) is the correct explanation of (A).
  2. B) (A) is false, but (R) is true.
  3. C) Both (A) and (R) are true, but (R) is not the correct explanation of (A).
  4. D) (A) is true, but (R) is false.
Match list-I with list-Il and select the correct answer using code given below—
List - I List - II (Diseases) (Factors)

(A) Peptic ulcers - (1) Virus
(B) Dengue - (2) Protozoa
(C) Elephant Foot - (3) Worm
(D) Malaria - (4) Bacteria
Code -
  1. A) A-(4), B-(2), C-(3), D-(1.)
  2. B) A-(4), B-(1), C-(3), D-(2)
  3. C) A-(4), B-(1), C-(2), D-(3)
  4. D) A-(1), B-(4), C-(3), D-(2)
Ultra-violet radiation from sun light causes the reaction that produce which of the following?
  1. A) CO
  2. B) SO2
  3. C) O3
  4. D) Fluorides
The "blue moon" phenomenon occurs:
  1. A) When two full moons occur in the same month
  2. B) When four full moons appear in two consecutive months of the same calendar year.
  3. C) when two full moons appear in the same month thrice in a calendar year
  4. D) None of the above.
The movement of nutrient elements through the various components of an ecosystem is called.
  1. A) Bio-geo-chemical cycle
  2. B) Bio-geological cycle
  3. C) Ecological succession
  4. D) Biological cycle
Match List-I and List-II and select the correct answer from the code given below the lists:
List-I - List-II

A. Sour Milk - 1. Malic acid
B. Vinegar and pickle - 2. Carbonic acid
C. Soda water and cold drinks 3. Acetic acid
D. Apple - 4. Lactic acid

Code:
A B C D
  1. A) 1 2 3 4
  2. B) 4 3 1 2
  3. C) 4 3 2 1
  4. D) 3 4 2 1
When the TV is switched ON then:
  1. A) Both audio and visuals start simultaneously
  2. B) The audio is heard immediately but the video is visible later because the video needs some practice time
  3. C) The visual starts immediately but audio is heard later because the sound travels less than the speed of light
  4. D) It depends on the brand of TV
Which of the following is not a part of the Article 20 of the Constitution of India?
  1. A) Prohibition against Self Incrimination
  2. B) Double Jeopardy Clause
  3. C) Prohibition Against Torture
  4. D) Ex-post Facto Law Torture
The colour of the Star is an indication of its
  1. A) distance from earth
  2. B) temperature
  3. C) luminosity
  4. D) distance from the Sun