General Knowledge (NDA/NA SOLVED PAPER 2023-I) (Part – B) (51 to 100)

Total Questions: 50

21. One advantage of sexual reproduction over asexual reproduction is that it helps species to survive over long evolutionary time. This is because sexual reproduction produces:

Correct Answer: (d) more variation in offspring.
Solution:Sexual reproduction involves two parents, whereas asexual reproduction involves only one parent. The offspring resulting from sexua! reproduction therefore have characteristics from both the parents and therefore, will be different from each parent. This will bring variations in the population. Variations are important for the survival of species over time.

22. Which one of the following structures or components is not always present in living cells?

Correct Answer: (a) Cell wall
Solution:Cell Wall is the characteristics of plant cell only and not the all types of cell including animal cells. Plasma membrane, cytoplasm, genetic material these all are essential cell component.
The Plasma Membrane is a double membranous cell organelle, composed of the phospholipid bilayer and is present both in prokaryotic and eukaryotic cells.
Cytoplasm is the fluid inside a cell but outside the cell's nucleus. Most chemical reactions in a cell take place in the cytoplasm.
The part of the cell which carries the genetic information that can be inherited is called genetic material. It is necessary for the reproduction and propagation of genes from one generation to another. DNA/RNA are types of genetic material inside a cell.

23. Browning of the chopped apple can be minimized by:

Correct Answer: (c) using lemon juice.
Solution:Browning of the chopped apple can be minimized by adding lemon juice or similar types of antioxidants. "Enzymatic browning of apple occurs when the sliced pieces are exposed to oxygen. This triggers an enzyme known as polyphenol oxidase (PPO) which oxidizes 87 polyphenols in the apple's flesh and turn it into brown.

24. Which of the hydrocarbons are arranged as per the increasing order of their boiling points?

Correct Answer: (b) Propane, Butane, Pentane, Octane
Solution:Boiling points of alkenes increases with their molecular masses due to stranger intermolecular forces.
The order of their masses is:-
Methane < Ethane < Propane < Butane < Pentane <
Hexane < Heptane < Octane
Thus, the boiling points increases in the same order.
Therefore, (b) propane < butane < pentane < octane <, is the correct option

25. Which one of the following apparatus is sued for separating benzene and water mixture?

Correct Answer: (c) Separating funnel
Solution:Benzene and water form an immiscible mixture and can be separated by a separating funnel wherein benzene forms the upper layer and can be separated. Dean and Stark apparatus is used for mixtures that are separated by distillation.

26. An iron nail dipped in copper sulphate solution turns brown. This is due to which one of the following types of reactions?

Correct Answer: (d) Displacement reaction
Solution:The brown colour is due to Cu deposits and this is a displacement reaction.

27. Among the following, which is not the correct method for keeping the curd?

Correct Answer: (b) Keeping in copper vessel
Solution:Curd contains acids that might react with the metallic copper so it should not be kept in a copper vessel. Other materials are not reactive.

28. Toothpaste prevents tooth decay by:

Correct Answer: (e) both (a) and (c)
Solution:Toothpaste prevents tooth decay by neutralizing excess acidity.

29. Freedom fighter Kanaklata Barua was martyred in:

Correct Answer: (b) Quit India Movement
Solution:(b)

30. Which one among the following statements about the Mansabdari system is correct?

Correct Answer: (b) Mansabs were usually assigned on the basis of ancestry.
Solution:The term mansabdar refers to an individual who holds a mansab, meaning a position or rank. It was a grading system used by the Mughals to fix rank, salary and military responsibilities. Rank and salary were determined by a numerical value called zat. The higher the zat, the more prestigious was the noble's position in court and the larger his salary.