English (Part – B) (General studies) NDA/NA SOLVED PAPER 2019 (II) (51 to 100)

Total Questions: 50

21. Which one of the following statements regarding lenses is not correct?

Correct Answer: (b) A concave lens produces both real and virtual images
Solution:

A concave lens always formes virtual image, whereas convex lens forms both real and virtual images.
Hence, option (b) is incorrect

22. 10 g of ice at −10° C is mixed with 10 g of water at 0°C. The amount of heat required to raise the temperature of mixture to 10°C is:

Correct Answer: (c) 1050 cal
Solution:

23. Which one of the following does not represent the salt, calcium carbonate?

Correct Answer: (a) Lime water
Solution:

Calcium carbonate is also known as limestone and has a molecular formula is CaCO3 . It is found in nature in the form of chalk, marble etc. Thus, limestone. chalk and marble represents calcium carbonate. Whereas, lime water is the aqueous solution ofCa(OH)₂.
Thus, the correct option is (a).

24. Soaps clean surfaces on the principle of based on:

Correct Answer: (d) surface tension
Solution:

Soaps clean surfaces on the principle of based on surface tension. Soap is a surface active agent or surfactant. It helps to reduce the surface tension of water and thereby speed up the cleaning process of soaps.

25. Which one of the following substances is not a mixture?

Correct Answer: (a) Tin
Solution:

A mixture is a type of matter which has variable composition throughout. Among the given options, only Sn(tin) is not a mixture, while rest are the examples of mixture. Sn is an element which contains only one kind of particles or atoms.

26. Which one of the following is termed as ‘dry ice’?

Correct Answer: (c) Solid state of carbon dioxide
Solution:

When liquefied CO₂ is allowed to expand rapidly, it gets converted in the form of solid CO₂ which is also called dry ice. Thus, dry ice is solid state of the carbon dioxide.

27. Net movement of water from a dilute to a concentrated solution through a selectively permeable membrane is called:

Correct Answer: (c) Osmosis
Solution:

The net movement of water from a dilute to concentrated solution through a selectively permeable membrane is called osmosis. This term is used specifically to refers to the diffusions of water across semi or selectively permeable membrane.
Water moves from a region of higher concentration to a region of lower concentration until an equilibrium is reached.

28. Blood is a type of:

Correct Answer: (d) connective tissue
Solution:

Blood is a type of connective tissue, which forms 30-32% of total extracellular fluid. The connective tissues have a special function of linking and supporting other tissues/organs of the body.
Blood is a fluid, which helps in the transportation of various substances in the body. It is red because it contains a red pigment called haemoglobin in its red blood cells.

29. Mitochondria are able to produce their own:

Correct Answer: (b) proteins
Solution:

Mitochondria are able to produce their own protein. It acts as the cell’s power producer and also called as powerhouse of the cell.
It possesses single circular DNA molecules, a few RNA molecules, ribosomes and the components required for the synthesis of proteins. It provides energy for energy requiring processes of the cell like muscle contraction, nerve impulse, conduction, etc. It may store and release calcium when required.

30. Which one of the following statements is correct?

Correct Answer: (a) Xylem consists of tracheids, vessels, xylem parenchyma and xylem fibres
Solution:

The statement given in option (a) is correct. Rest of the statements are incorrect and can be corrected as
(b) Flexibility in plants is due to the permanent tissue collenchyma. Sclerenchyma provides mechanical support to organs.
(c) Parenchyma cells are thin walled with small intercellular spaces.
(d) Phloem consists of sieve plates, sieve tube and companion cells.