| A | B |
|---|
| Transformation | process in which one strain of bacteria is changed by a gene or genes from another strain of bacteria |
| Bacteriophage | virus that infects bacteria |
| Nucleotide | monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base |
| Base pairing | principle that bonds in DNA can form only between adenine and thymine and between guanine and ctyosine |
| Chromatin | granular material visible within the nucleus; consists of DNA tightly coiled around proteins |
| Histone | globular protein molecule around which DNA is tightly coiled in chromatin |
| Replication | copying process by which a cell duplicates its DNA |
| DNA polymerase | enzyme tyhat "proofreads" new DNA strands, helping to ensure that each molecule is a nearly perfect copy of the original DNA |
| Messenger RNA | RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell |
| Ribosomal RNA | type of RNA that makes up a major part of ribosomes |
| Transcription | process in which part of the nucleotide sequence of DNA is copied into a complementary sequence of RNA |
| RNA polymerase | enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription |
| Promoter | region of DNA that indicates to an enzyme where to bind to make RNA |
| Intron | intervening sequence of DNA; does not code for a protein |
| Exon | expressed sequence of DNA; codes for a protein |
| Codon | three-nucleotide sequence on messenger RNA that codes for a single amino acid |
| Translation | decoding of mRNA messages into a polypeptide chain |
| Anticodon | group of three bases on tRNA molecule that are complementary to an mRNA codon |
| Mutation | change in DNA sequence that affects genetic information |
| Point mutation | mutation that affects a single nucleotide, usually by substituting one nucleotide for another |
| Frameshift mutation | mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide |
| Operon | group of genes operating together |
| Operator | region of chromosomes is an operon to which the repressor binds when the operon is "turned off" |
| Hox genes | series of genes that controls the organs and tissues that develop in various parts of an embryo |
