Biology · Chemistry
Biomolecules and Enzymes
1,432 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
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Cystine and Threonine
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Cysteine and Methionine
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Methionine and Lysine
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Lysine and threonine
B
Correct answer
Explanation
Cysteine (Chemical formula HO2CCH(NH2)CH2SH): Sulphur containing amino acid
Methionine (Chemical formula HO2CCH(NH2)CH2CH2SCH3): Sulphur containing amino acid
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valine
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leucine
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lysine
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phenylalanine
C
Correct answer
Explanation
Lysine has a basic, polar hydrophilic side chain: -CH2(CH3)2-NH2.
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serine
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glycine
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leucine
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all of the above
B
Correct answer
Explanation
Glycine, or aminoethanoic acid (NH2CH2COOH) is the only amino acid that is not optically active as it does not contain a chiral carbon.
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primary structure only
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secondary structure only
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primary, secondary and tertiary structures
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secondary, tertiary and quaternary structures
D
Correct answer
Explanation
Denaturation of proteins involves the disruption and possible destruction of secondary, tertiary and quaternary structures.
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<span style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-font-family:"Times" new="lang=EN-GB">co-factor
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<span style="font-size:10.0pt;font-family:Arial,sans-serif;mso-fareast-font-family:Times" new="lang=EN-GB">co-enzyme
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<span style="font-size:">prosthetic group
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<span style="font-size:">activator
A
Correct answer
Explanation
A co-factor is the non-protein chemical compound that is bound to a protein and is required for the protein's biological activity. These proteins are commonly enzymes, and co-factors can be considered helper molecules that assist in biochemical transformations.
Match the following:
| |
|
| Names of proteins |
Functions |
| a. Fibrinogens |
1. They help in maintaining the osmotic balance. |
| b. Globulins |
2. They are primarily involved in defence mechanisms of the body. |
| c. Albumins |
3. They are needed for coagulation of blood. |
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a - 3, b - 2, c - 1
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a - 3, b - 1, c - 2
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a - 1, b - 3, c - 2
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a - 2, b - 3, c - 1
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a - 1, b - 2, c - 3
A
Correct answer
Explanation
This is the correct option. Fibrinogens are needed for coagulation of blood. Globulins are primarily involved in defence mechanisms of the body. Albumins help in maintaining the osmotic balance.
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Sugars
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Nucleotides
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Dextrins
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Amino acids
D
Correct answer
Explanation
Amino acids are the monomers of proteins.
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Glycine
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Proline
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Alanine
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Valine
A
Correct answer
Explanation
Glycine derived from glyceraldehyde has no optical activity as it is not chiral (achiral).
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Casein
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Histone
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Collagen
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Myoglobin
A
Correct answer
Explanation
Casein is a phosphoprotein.
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glycoproteins
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phosphoproteins
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metalloprotein
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lipoprotein
C
Correct answer
Explanation
Ceruloplasmin is a blue copper protein (Metalloprotein) found in the alpha 2-globulin fraction of vertebrate plasma. It is a single-chain glycoprotein of molecular weight 132 000. It contains six copper atoms per molecule, comprising three or possibly four different types of copper.
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peptide bonds
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hydrogen bonds
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van der Waals forces
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All of the above
B
Correct answer
Explanation
In α-helix structure, proteins are stabilised by hydrogen bonds.
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high concentration of Mg++ ions
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low concentration of Mn++ ions
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high concentration of Ca++ ions
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low concentration of Mg++ ions
A
Correct answer
Explanation
Ribosome is large & complicated cell organelle presents in almost all living cell that serevs as the major site of biological protein synthesis. 2 ribosomal sub-units remain together with each other because of high concentration of Mg++ ions.
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H1 protein
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H2 protein
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HU protein
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H3 protein
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H4 protein
C
Correct answer
Explanation
HU is the most abundant protein in prokaryotes.
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Slubility
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Svedberg subunit
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Sdimentation coefficient
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Both 2 and 3
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None of the above
D
Correct answer
Explanation
‘S ‘ denotes both Svedberg subunit and Sedimentation coefficient.
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Transition
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Frameshift mutation
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Transversion
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Chromosome mutation
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Point mutation
B
Correct answer
Explanation
This type of mutation causes a change in all the amino acids downstream.