Q. 41. The technique used for the early diagnosis of genetic disorders is
Western blotting
ELISA
PCR
Spectrophotometry
Answer:
(C) PCR
Explanation:
Polymerase Chain Reaction (PCR) allows for the massive amplification of small DNA sequences, making it highly effective for the early diagnosis and detection of genetic mutations and disorders.
Q. 42. Which of the following is used as an anti-freeze in automobile engines?
Methanol
Ethanol
Propanol
Ethylene glycol
Answer:
(D) Ethylene glycol
Explanation:
Ethylene glycol lowers the freezing point and raises the boiling point of water, making it the most common and effective antifreeze/coolant used in internal combustion engines.
Q. 43. Which among the following polymers is used in making bulletproof vests?
Polyethylene
Polystyrene
Kevlar
Teflon
Answer:
(C) Kevlar
Explanation:
Kevlar is a heat-resistant, immensely strong synthetic polymer fiber that has a high tensile strength-to-weight ratio, making it the primary material for bulletproof vests and body armor.
Q. 44. Biodegradable plastics are mainly made from:
Polyvinyl alcohol (PVA)
Polystyrene
Polyhydroxyalkanoates (PHA)
Polyethylene
Answer:
(C) Polyhydroxyalkanoates (PHA)
Explanation:
PHAs are polyesters naturally produced in nature by numerous microorganisms through bacterial fermentation of sugar or lipids, resulting in completely biodegradable plastics.
Q. 45. Which of the following is used as a preservative in food and soft drinks?
Calcium carbonate
Sodium chloride
Sodium benzoate
Potassium nitrate
Answer:
(C) Sodium benzoate
Explanation:
Sodium benzoate (E211) is widely used as a preservative in acidic foods and carbonated soft drinks to prevent the growth of mold, yeast, and some bacteria.
