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
-
Aminoacyl
-
Exit
-
Initiator
-
Peptidyl
-
proteins
-
monomers
-
water
-
polymers
C
Correct answer
Explanation
A hydrolysis reaction is a chemical process in which a molecule of water is added to a substance to break its chemical bonds. Therefore, water is always a reactant in these reactions.
-
Active Site
-
Substrate
-
None of the above
-
Allosteric Site
B
Correct answer
Explanation
The substrate is the specific reactant molecule that binds to an enzyme's active site, where it undergoes a chemical reaction to be converted into products.
-
Carbohydrate
-
Protein
-
Lipid
-
Nucleic Acid
B
Correct answer
Explanation
In biochemical nomenclature, molecules ending with the suffix '-ase' are enzymes (such as lactase, amylase, or helicase). Since enzymes are specialized catalytic proteins, they belong to the protein class of macromolecules.
-
Carbohydrate
-
Protein
-
Lipid
-
Nucleic Acid
A
Correct answer
Explanation
In biochemistry, chemical names ending in the suffix '-ose' represent sugars, which are carbohydrates (such as glucose, fructose, and sucrose). Proteins, lipids, and nucleic acids do not follow this naming convention.
-
Hydrocarbon chains
-
Amino acids
-
mRNA nucleotides
-
Polypeptide chains
D
Correct answer
Explanation
Protein synthesis links amino acids together via peptide bonds to form polypeptide chains, which then fold into functional proteins. Amino acids are the individual building blocks, not the final product of the synthesis process.
-
Elastin
-
Collagen
-
Glycoaminoglycan
-
Chitin
A
Correct answer
Explanation
Elastin is a highly elastic protein in connective tissue that allows many tissues in the body to resume their shape after stretching or contracting. Collagen provides tensile strength rather than rubber-like elasticity, while glycosaminoglycans are carbohydrate chains in the ground substance, and chitin is a structural polysaccharide found in fungi and arthropods.
-
Cell adhesion proteins
-
Enzymes
-
Digestive proteins
-
Protein fibers that make up fibrous connective tissue
A
Correct answer
Explanation
Fibronectin and laminin are glycoproteins of the extracellular matrix that function as cell adhesion proteins, anchoring cells to the matrix and guiding cell migration. They are not enzymes or digestive proteins, nor do they form the primary structural fibers like collagen or elastin.
-
Collagen
-
Elastin
-
Enzyme
-
Gluten
D
Correct answer
Explanation
Gluten is the primary composite protein found in wheat, barley, and rye, giving dough its elasticity and chewiness. Collagen and elastin are structural proteins found in animal tissues, while enzymes are biological catalysts.
A
Correct answer
Explanation
Proteins are large biomolecules made up of long chains of smaller building blocks called amino acids. These amino acids are linked together by peptide bonds to form complex three-dimensional structures.
A
Correct answer
Explanation
Mycoprotein, which is the main ingredient in Quorn products, is a fungi-derived protein source used as a meat substitute. It serves as an excellent protein alternative for vegetarians, vegans, and those looking to reduce meat consumption.
-
incomplete
-
complete
-
complementing
-
complate
B
Correct answer
Explanation
A complete protein contains all nine essential amino acids that the human body cannot synthesize on its own and must obtain from the diet. Incomplete proteins lack one or more of these essential amino acids.
-
complete protein
-
incomplete protein
-
complementing protein
-
totally awesome protein
C
Correct answer
Explanation
Complementing proteins (or complementary proteins) are two or more incomplete protein sources that, when eaten together, compensate for each other's lack of specific essential amino acids to provide a complete protein profile.
-
amino acids
-
fatty acids
-
monosaccharides
-
water
A
Correct answer
Explanation
Proteins are polymers made up of long chains of monomeric units called amino acids. Fatty acids are building blocks of lipids, and monosaccharides are building blocks of carbohydrates.
A
Correct answer
Explanation
Ribosomes are the cellular structures responsible for protein synthesis, translating messenger RNA (mRNA) into polypeptide chains.