Science Group
Explore subjects and practice MCQs
7
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Total MCQs
Science Group
Answer: Translation is the process in which ribosomes use mRNA to assemble a chain of amino acids into a protein.
Answer: Enzyme activity increases with temperature up to an optimum, beyond which heat denatures the enzyme.
Answer: Chromosomes are composed mainly of DNA, which carries the genes.
Answer: The active site is the specific region of an enzyme where the substrate attaches and reacts.
Answer: Guanine and cytosine pair through three hydrogen bonds, making their pairing stronger than A-T.
Answer: Enzymes are proteins that act as biological catalysts to speed up chemical reactions without being consumed.
Answer: High temperature breaks the bonds of the enzyme, denaturing it and destroying its active site permanently.
Answer: The substrate is the reactant molecule that binds to the active site of the enzyme.
Answer: Most cellular enzymes have an optimum pH near neutrality, around pH 6 to 8.
Answer: Sugar and phosphate groups alternate to form the DNA backbone, with bases projecting inward.
Answer: Salivary amylase is an enzyme that begins breaking starch down into simpler sugars in the mouth.
Answer: Iodine is needed for thyroid hormone production, and its deficiency causes goiter.
Answer: Calcium and phosphorus form the hard mineral part of bones and teeth.
Answer: Iron is an essential component of hemoglobin, which carries oxygen in the blood.
Answer: Chitin is a structural polysaccharide that forms the hard exoskeleton of insects and crustaceans.
Answer: Water acts as a universal solvent in which many biochemical reactions of the body take place.
Answer: Ascorbic acid is the chemical name of vitamin C, found in citrus fruits and vegetables.
Answer: A water molecule consists of two hydrogen atoms and one oxygen atom, written as H2O.
Answer: Vitamin D deficiency causes rickets, a disease of weak and deformed bones in children.
Answer: The secondary structure (alpha-helix and beta-pleated sheet) is stabilized by hydrogen bonds.