Biology ยท Chemistry
Biomolecules and Enzymes
1,501 Questions
This topic focuses on biomolecules, specifically proteins, enzymes, and amino acids. It includes questions on enzyme structures, protein folding, and catalysis. These concepts are crucial for medical and biology competitive exams.
Enzyme catalysisProtein structuresAmino acid synthesisPolypeptide chainsBiomolecule properties
Biomolecules and Enzymes Questions
What is the primary component of amyloid plaques, a hallmark of Alzheimer's disease?
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Tau protein
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Beta-amyloid peptide
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Alpha-synuclein
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Huntingtin protein
B
Correct answer
Explanation
Amyloid plaques are primarily composed of beta-amyloid peptide, which forms aggregates that are toxic to neurons.
Which protein is associated with the formation of neurofibrillary tangles in Alzheimer's disease?
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Tau protein
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Beta-amyloid peptide
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Alpha-synuclein
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Huntingtin protein
A
Correct answer
Explanation
Neurofibrillary tangles are composed primarily of hyperphosphorylated tau protein, which aggregates and disrupts neuronal function.
What is the main protein found in pulses?
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Albumin
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Globulin
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Glutelin
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Prolamin
B
Correct answer
Explanation
The main protein found in pulses is globulin.
What is the main amino acid found in pulses?
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Lysine
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Methionine
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Threonine
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Tryptophan
A
Correct answer
Explanation
The main amino acid found in pulses is lysine.
Which of the following is a common file format used for storing chemical structure data?
A
Correct answer
Explanation
MOL is a common file format used for storing chemical structure data.
What is the primary protein found in milk?
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Casein
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Whey
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Albumin
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Globulin
A
Correct answer
Explanation
Casein is the primary protein found in milk. It is a phosphoprotein that makes up about 80% of the total protein content of milk. Casein is responsible for the formation of curds when milk is heated or acidified.
Which of the following amino acids is nonpolar?
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Serine
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Alanine
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Aspartic acid
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Lysine
B
Correct answer
Explanation
Alanine is a nonpolar amino acid due to its side chain being a methyl group, which is hydrophobic.
The primary structure of a protein refers to:
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The sequence of amino acids
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The three-dimensional arrangement of amino acids
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The interactions between amino acids and other molecules
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The overall shape of the protein
A
Correct answer
Explanation
The primary structure of a protein is the linear sequence of amino acids linked by peptide bonds.
Which of the following forces is responsible for maintaining the secondary structure of a protein?
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Hydrogen bonds
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Ionic bonds
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Covalent bonds
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Disulfide bonds
A
Correct answer
Explanation
Hydrogen bonds between the backbone atoms of amino acids are responsible for maintaining the secondary structure of a protein, such as alpha helices and beta sheets.
The tertiary structure of a protein refers to:
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The arrangement of amino acids in space
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The interactions between amino acids and other molecules
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The overall shape of the protein
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The sequence of amino acids
A
Correct answer
Explanation
The tertiary structure of a protein is the three-dimensional arrangement of amino acids in space, including the folding of the polypeptide chain.
Which of the following is an example of a globular protein?
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Collagen
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Myoglobin
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Keratin
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Actin
B
Correct answer
Explanation
Myoglobin is a globular protein with a compact, spherical shape, while collagen, keratin, and actin are fibrous proteins with elongated structures.
The quaternary structure of a protein refers to:
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The arrangement of multiple polypeptide chains
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The interactions between amino acids and other molecules
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The overall shape of the protein
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The sequence of amino acids
A
Correct answer
Explanation
The quaternary structure of a protein is the arrangement of multiple polypeptide chains into a single functional unit.
Which of the following is an example of a protein with a quaternary structure?
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Insulin
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Hemoglobin
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Collagen
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Myoglobin
B
Correct answer
Explanation
Hemoglobin is a protein with a quaternary structure, consisting of four polypeptide chains.
The structure of a protein is determined by:
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The sequence of amino acids
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The interactions between amino acids and other molecules
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The environment in which the protein is located
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All of the above
D
Correct answer
Explanation
The structure of a protein is determined by the sequence of amino acids, the interactions between amino acids and other molecules, and the environment in which the protein is located.
The function of a protein is determined by:
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Its structure
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Its interactions with other molecules
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The environment in which it is located
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All of the above
D
Correct answer
Explanation
The function of a protein is determined by its structure, its interactions with other molecules, and the environment in which it is located.