Question | Answer |
Amino group | A functional group that consists of a nitrogen atom bonded to two hydrogen atoms. |
Carboxyl group | A functional group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group. |
Codon | A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code. |
Exon | A coding region of a eukaryotic gene. Exons, which are expressed, are separated from each other by introns. |
Gene | A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA. |
Hydrophilic | Having an affinity for water |
Hydrophobic | Having an aversion to water; tending to coalesce and form droplets in water. |
Hydroxyl group | A functional group consisting of a hydrogen atom joined to an oxygen atom by a polar covalent bond. Molecules possessing this group are soluble in water and are called alcohols. |
Intron | A non-coding, intervening sequence within a eukaryotic gene. |
Messenger RNA (mRNA) | A type of RNA, synthesized from DNA and attaches to ribosomes in the cytoplasm; it specifies the primary structure of a protein. |
Mutation | A rare change in the DNA of a gene, ultimately creating genetic diversity. |
Nucleotide | The building block of a nucleic acid, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group. |
Primary Structure | The level of protein structure referring to the specific sequence of amino acids. |
Quaternary Structure | The particular shape of a complex, aggregate protein, defined by the characteristic three-dimensional arrangement of its constituent subunits, each a polypeptide. |
Ribonucleic Acid (RNA) | A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses. |
Ribosome | A cell organelle that functions as the site of protein synthesis in the cytoplasm; consists of ribosomal RNA and protein molecules, and is formed by combining two subunits. |
Secondary Structure | The localized, repetitive coiling or folding of the backbone of a protein due to hydrogen bond formation between amino acids. |
Tertiary Structure | Irregular contortions of a protein molecule due to interactions of side chains involved in hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges. |
Transcription | The synthesis of RNA on a DNA template. |
Transfer RNA (tRNA) | An RNA molecule that functions as an interpreter between nucleic acid and protein language by picking up specific amino acids and recognizing the appropriate codons in the mRNA. |
Translation | The synthesis of a polypeptide using the genetic information encoded in an mRNA molecule. There is a change of language from nucleotides to amino acids. |