All Free Biology MCQs with Answers
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19844 questions · page 510 of 1985
5091. Which of the following compounds are added to wax for the preparation of candles?[A] Palmitic acid [B] Stearic acid[C] Arachidonic acid [D] Linoleic acid
- A. A and C
- B. A and B
- C. B and C
- D. B and D
Explanation: Linoleic acid and arachidonic acid are polyunsaturated omega-6 fatty acid whereas palmitic acid and stearic acid are saturated fatty acids added to wax for preparation of candles.
Correct answer: A and B5092. Which of the following compounds is an example of an non-ionic detergent?
- A. Trimethylcerylammonium bromide
- B. Sodium lauryl sulphonate
- C. Pentaerythritolmonostearate
- D. Sodium cetylsulphate
Explanation: Pentaerythritolmonostearate(C23H46O5) is an example of a non-ionic detergent. Non-ionic detergents do not carry a net charge and are commonly used in laundry detergents, as they are gentle on fabrics and are less likely to cause skin irritation.
Correct answer: Pentaerythritolmonostearate5093. Soaps and detergents are kept in the family of which of the following types of compounds?
- A. Surface active
- B. Surface inactive
- C. Water soluble
- D. Water insoluble
Explanation: Soaps and detergents are surface-active agents, also known as surfactants. They possess both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts in their molecular structure. This dual nature allows them to interact with both water and oil, enabling them to act as cleansing agents that emulsify and lift away dirt and grease from surfaces.
Correct answer: Surface active5094. Brazil wax is also known by the following other name?
- A. Wool wax
- B. Carnauba wax
- C. Beeswax
- D. Spermaceti wax
Explanation: Carnauba wax is a natural wax obtained from the leaves of the Copernicia prunifera palm plant.This plant is found only in Brazil so it is also known as Brazil wax.
Correct answer: Carnauba wax5095. Example of monopropellants is:
- A. CH3O2
- B. Hydrazine
- C. H2 and O2
- D. All of these
Explanation: Monopropellants are substances used in rocket propulsion that decompose or react without needing an additional oxidizer to produce thrust.Hydrazine (N2H4) is an example of a monopropellant commonly used in rocket propulsion. It decomposes exothermically, releasing heat and gas to generate thrust.
Correct answer: Hydrazine5096. Paracetamol contains:
- A. -OH and -NHCHO groups
- B. -OH and -NHCH2 groups
- C. --NHCO CH3 and -SO2NH2 group
- D. -OH and -NHCOCH3 groups
Explanation: Paracetamol contains a hydroxyl group (-OH) and an amide group (-NHCOCH3), which is also referred to as the acetamide group.
Correct answer: -OH and -NHCOCH3 groups5097. The substance which affects the Central Nervous System and induces sleep are called:
- A. Antipyretics
- B. Tranquilizers
- C. Analgesics
- D. None of above
Explanation: Tranquilizers, also known as sedatives or hypnotics, are drugs that act on the CNS to reduce anxiety, promote relaxation, and induce sleep.
Correct answer: Tranquilizers5098. Sulpha drugs are derivatives of:
- A. Benzenesulphonic acid
- B. Sulphanilic acid
- C. Sulphanilamide
- D. p-Aminobenzoic acid
Explanation: Sulphanilamide is the parent compound and the first sulfonamide antibiotic. It served as the foundation for the development of other sulfonamide drugs, which played a crucial role in early antibiotic therapy.
Correct answer: Sulphanilamide5099. Zigzag and regular coiling of polypeptide linkage forms:
- A. Primary structure
- B. Secondary structure
- C. Tertiary structure
- D. Quaternary structure
Explanation: The secondary structure of a protein is a regular coiling or zigzagging of polypeptide chains caused by hydrogen bonding between N-H and C=O groups of amino acids near each other in the chains.
Correct answer: Secondary structure5100. The hydrogen bond in secondary structure of protein is present between:
- A. O-H
- B. N-H
- C. C-H
- D. F-H
Explanation: The secondary structure of a protein is a regular coiling or zigzagging of polypeptide chains caused by hydrogen bonding between NH and C = 0 groups of amino acids near each other in the chains. Here, the hydrogen bond forms between the oxygen of the carboxyl group and the hydrogen of the amine group.
Correct answer: O-H