| dna | deoxyribonucleic acid; the unique genetic code for every living thing. |
| Watson and Crick | Scientists who proposed the double helix structure of DNA |
| adenine | The base that pairs with Thymine in DNA |
| thymine | The base that pairs Adenine in DNA |
| cytosine | The base that pairs with Guanine with DNA |
| guanine | The base that pairs with Cytosine in DNA |
| Thomas Morgan | Documented sex-linked traits in fruit flies |
| replication | The process by which a cell makes a copy of the DNA in its nucleus |
| Deoxyribose | A five-carbon sugar found in DNA. |
| Phosphate group | alternates with deoxyribose to make up the sides of DNA |
| Griffith | used mice to discover that genetic material had a transforming factor, |
| Hershey and Chase | Identified DNA to be genetic material through experiments with bacteriophages |
| Initiation | DNA replication is initiated when helicase enzyme breaks the hydrogen bonds holding the base pairs together and the DNA uncoils. |
| Elongation | Addition of nucleotides on uncoiled DNA through polymerase. |
| Ligase | The enzyme that joins DNA fragments together |
| RNA | Ribonucleic acid; a nucleic acid that plays an important role in the production of proteins |
| Protein synthesis | The assembly of chains of amino acids into functional protein molecules |
| Uracil | a nitrogen-containing base found in RNA (but not in DNA) |
| mRNA | Messenger RNA; the RNA molecule that serves as the template for protein synthesis. |
| tRNA | Transfer RNA; the type of RNA that carries an amino acid from the cytoplasm to the ribosome for incorporation into a growing protein. |
| rRNA | Ribosomal RNA; the type of RNA that associates with ribosomal proteins to make a functional ribosome. |
| Transcription | A process in which DNA is used as a template to make complementary messenger RNA. |
| Translation | The assembly of a protein on a ribosome, using mRNA to direct the order in wich amino acids are added to the protein being made. |
| AUG | Start codon for protein synthesis. |
| ribosome | A cell organelle which functions as the site of protein synthesis in the cytoplasm; consists of rRNA and protein molecules, which make up two subunits. |
| exons | coding regions; parts of a gene that are expressed as amino acids |
| introns | sequences of nucleotides not involved in coding for proteins |
| oncogenes | genes that cause cancer by blocking the normal controls on cell reproduction |
| structural genes | a DNA sequence that codes for a specific product |
| repressor protein | a regulatory protein that binds to an operator and blocks transcription of the genes of an operon |
| operator gene | controls the activity of the structured genes (switches on/off to control transcription) |
| mutations | change in the nucleotide sequence of DNA |
| Substitution Mutation | A single nucleotide is replaced by a different nucleotide |
| missense mutation | a type of point mutation that results in an alternate incorrect amino acid to be coded; produces a disfunctional protein |
| nonsense mutation | a mutation that changes an amino acid codon to one of the 3 stop codons, resulting in a shorter and usually nonfunctional protein |
| silent mutation | a type of point mutation in which no harmful effect is produced |