Free Biological Molecules MCQs with Answers
1,790 Biological Molecules MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The chapter covers water's polarity and biological roles, carbohydrates, lipids, proteins and nucleic acids, including their monomers, bonds, structures and functions. It also distinguishes RNA from DNA and explains conjugated molecules such as glycoproteins, glycolipids and nucleoproteins, which combine organic molecules with a non-protein component.
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1,790 questions · page 64 of 90
- 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: Tranquilizers- A. Benzenesulphonic acid
- B. Sulphanilic acid
- C. Sulphanilamide
- D. p-Aminobenzoic acid
Explanation: Sulphanilamide is the parent compound and the first sulfonamide antibiotic.
Correct answer: Sulphanilamide- 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…
Correct answer: Secondary structure- 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…
Correct answer: O-H- A. Folding
- B. Sequence of amino acids
- C. Coiling
- D. It is due to hydrogen bonding
Explanation: The primary structure of a protein refers to the linear sequence of amino acids that make up the protein chain.
Correct answer: Sequence of amino acids- A. Peptide bond is a covalent bond
- B. It is a polyamide
- C. It contain different sequence of amino acids in different proteins
- D. Primary structure is due to hydrogen bonding
Explanation: The primary structure of a protein refers to its linear sequence of amino acids linked by peptide bonds.
Correct answer: Primary structure is due to hydrogen bonding1267. Which one of the following structure of protein is the direct consequence of hydrogen bonding:
- A. Primary
- B. Tertiary
- C. Secondary
- D. Quaternary
Explanation: The secondary structure of a protein is a regular coiling or zigzagging of polypeptide chains caused by hydrogen bonding between NH and C…
Correct answer: Secondary- A. Hydrogen bonding
- B. Covalent bond
- C. Debye forces
- D. Dipole-Dipole forces
Explanation: Covalent bond is correct for the primary structure of proteins, as it refers to the bonds formed between the amino acids in the sequence…
Correct answer: Covalent bond- A. α-helix
- B. Both A and C
- C. β-sheets
- D. 3-dimensioal folding
Explanation: Alpha helices (A) and beta sheets (C) are types of secondary protein structures.
Correct answer: Both A and C- A. Result of replication
- B. Result of termination
- C. Result of duplication
- D. Result of translation
Explanation: Translation is the process where the sequence of nucleotides in mRNA is decoded into a sequence of amino acids, ultimately determining the…
Correct answer: Result of translation- A. H-Bond
- B. Disulphide linkage
- C. Covalent bond
- D. Amino acids
Explanation: Disulfide linkages are not typically found within α-helices. They form between cysteine residues in proteins, stabilizing tertiary protein…
Correct answer: Disulphide linkage- A. α-Carbon
- B. ẞ-Carbon
- C. Side chain carbon
- D. Carbonyl carbon
Explanation: This carbon atom is part of the carbonyl group (C=O) at the carboxyl end of an amino acid.
Correct answer: Carbonyl carbon- A. Organic polymers
- B. Inorganic polymers
- C. Biopolymers
- D. Synthetic polymers
Explanation: Most biologically important substances are organic compounds (Hiopolymers) built up from skeleton of carbon atoms.
Correct answer: Biopolymers- A. Terylene
- B. Nylon 6,6
- C. Protein
- D. Urea
Explanation: Within a protein, multiple amino acids are linked together by peptide bonds, thereby forming a long chain.
Correct answer: Protein- A. pH change
- B. Increase of temperature
- C. Oxidizing condition
- D. Dissolving in H2O
Explanation: The deformation or disruption of protein structure under specific conditions is called denaturation of proteins.
Correct answer: Dissolving in H2O- A. Carbon
- B. Hydrogen
- C. Sulphur
- D. Nitrogen
Explanation: All proteins contain the elements carbon, hydrogen, oxygen and nitrogen except sulphur.
Correct answer: Sulphur- A. Isomerases
- B. Lyases
- C. Transferases
- D. Ligases
Explanation: Isomerases are enzymes that catalyze the rearrangement of atoms within a molecule, converting one isomer into another.
Correct answer: Isomerases- A. Cellulose
- B. Urease
- C. L-asperginase
- D. Lactic dehydrogenase
Explanation: L-asparaginase is the correct option because it is an enzyme used in the treatment of blood cancer in children, particularly acute…
Correct answer: L-asperginase- A. Oxidoreductases
- B. Hydrolases
- C. Isoenzymes
- D. Isomerases
Explanation: Isoenzymes is the correct option because they are enzymes from the same organism that catalyze the same reaction but are chemically and…
Correct answer: Isoenzymes- A. Enzyme
- B. Substrate
- C. Enzyme and substrate
- D. Enzyme and product
Explanation: The rate of an enzymatic reaction is directly proportional to the concentration of substrate.
Correct answer: Substrate