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Unit-6 Moleculer Biology
Answer: Adenine pairs with thymine in DNA through two hydrogen bonds.
Answer: The three main types of RNA are messenger RNA, transfer RNA and ribosomal RNA.
Answer: Guanine pairs with cytosine through three hydrogen bonds.
Answer: Tertiary structure is the overall 3D folding of one polypeptide chain stabilized by various bonds.
Answer: Waxes are water-repellent lipids that waterproof plant leaves and animal feathers.
Answer: Messenger RNA copies the genetic information from DNA and carries it to ribosomes for protein synthesis.
Answer: Transfer RNA carries specific amino acids to the ribosome and matches them to the mRNA code.
Answer: Ribosomal RNA combines with proteins to build the ribosomes where proteins are made.
Answer: Transcription is the process in which the DNA sequence is copied into messenger RNA.
Answer: Water absorbs or releases large amounts of heat with little change in temperature, stabilizing body temperature.
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.