| A | B |
|---|
| adenine | a nitrogen containing base that is a component of a nucleotide |
| anticodon | a region of tRNA consisting of three bases complementary to the codon of mRNA |
| base pairing rules | the rule stating that in DNA, cytosine pairs with guanine and adenine pairs with thymine and in RNA, adenine pairs with uracil |
| codon | a group of three sequential nitrogen bases of an mRNA molecule |
| complementary base pair | cytosine pairs with guanine, and adenine pairs with thymine. The DNA nucleotides normally pair in these combinations |
| cytosine | a nitorgen containing base: a pyrimidine of DNA and RNA |
| deoxyribose | the sugar of DNA |
| DNA polymerase | an enzyme that binds to the separate strands of DNA and assembles each strand's complement in replication |
| double helix | DNA is composed of two nucleotide chains that wrap around each other to form a double spiral similar to a spiral staircase |
| genetic code | triplets of nucleotides in mRNA that determine the sequence of amino acid in protein |
| guanine | a nitrogen containing base that is a component of a nucleotide |
| helicase | an enzyme that separates DNA strands before replication |
| messenger RNA (mRNA) | the type of RNA that carries genetic information from the nucleus the ribosomes |
| mutation | a change in DNA |
| nitrogenous base | a DNA nucleotide containing nitrogen, a sugar molecule and a phosphate group |
| promoter | a nucleotide sequence on a DNA molecule that when attached to an RNA polymerase molecule, will initiate transcription of a specific structural gene |
| protein synthesis | the process in which amino acids are arranged in a linear sequence through the processes of transcription of DNA to RNA and the translation of RNA to a polypeptide chain |
| purine | an organic molecule that has a double ring of arbon and nitrogen atoms |
| pyrimidine | an organic molecule that has a single ring of carbon and nitrogen atoms |
| DNA replication | the process in which DNA makes a duplicate copy of itself |
| replication fork | the points at which the DNA strands separate during replication |
| ribose | the five carbon sugar in RNA |
| ribosomal RNA (rRNA) | the type of RNA found in a ribosome |
| RNA polymerase | the primary transcription enzyme |
| start codon | the codon AUG which engages a ribosome to start translating an mRNA molecule |
| stop codon | causes the ribosome to stop translating mRNA; UAA, UAG, UGA |
| termination signal | a specific sequence of nucleotides that marks the end of a gene in eukaryotes |
| thymine | a nitrogen containing base one component of a nucleotide |
| transcription | the process in which a strand of messenger RNA (mRNA) is synthesized by using the genetic information found on a DNA strand as a template |
| transfer RNA (tRNA) | the type of RNA that carries amino acids from the cytoplasm to the ribosome |
| translation | the process in which the messenger RNA (mRNA) molecule on a ribosome is decoded to produce a sequence of amino acids for protein synthesis |
| uracil | a nitrogen containing base found in DNA |
| gene expression | the process in which a nucleotide sequence of a gene is used to make functional product such as protein or RNA |
| semiconservative replication | the process in which the DNA molecule uncoils and separates into two strands. Each original strand becomes a template on which a new strand is constructed resulting in two DNA molecules idential to the original DNA molecule |
| virulent | describes a microorganism that causes disease and that is highly infectious |
| transformation | the transfer of genetic material in the form of DNA fragments from one cell to another or from one organism to another |
| bacteriophage | a virus that infects bacteria |
| nucleotide | in a nucleic acid chain, a subunit that consists of a sugar, a phosphate and a nitrogenous base |
| base sequence | the order of nitrogenous bases on a chain of DNA |
| genome | the complete genetic material contained in an individual |
| RNA (ribonucleic acid | a natural polymer that is present in all living cells and that plays a role in protein synthesis |
