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| 7600263595 | Transformation | change in genotype and phenotype due to the assimilation of external DNA by a cell; discovered by Griffith | 0 | |
| 7600263596 | Bacteriophages | viruses that infect bacteria | 1 | |
| 7600263599 | DNA Nucleotide | nitrogenous base, pentose sugar called deoxyribose, and a phosphate group | 2 | |
| 7600263600 | Adenine | nucleotide complementary to thymine in DNA | 3 | |
| 7600263601 | Guanine | nucleotide complementary to cytosine | 4 | |
| 7600263602 | Chargaff's Rules | 1) the base composition of DNA varies between species 2) the percentages of A and T bases are roughly equal | 5 | |
| 7600263603 | Double helix | shape of a DNA molecule but not of an RNA molecule | 6 | |
| 7600263604 | antiparallel | meaning the two sugar-phosphate backbones run in opposite directions (5' to 3' and 3' to 5') | 7 | |
| 7600263605 | Purine | adenine and guanine; having 2 organic rings | 8 | |
| 7600263606 | Pyrimidine | cytosine and thymine; single ring nitrogenous bases | 9 | |
| 7600263608 | Semiconservative model | model for replication in which two strands of the parental molecule separate, and each functions as a template for synthesis of a new, complementary strand; new molecules have one original strand and one new strand | 10 | |
| 7600263609 | Origins of replication | short stretches of DNA having a specific sequence of nucleotides; where replication begins | 11 | |
| 7600263610 | Replication fork | y-shaped region where the parental strands of DNA are being unwound | 12 | |
| 7600263611 | Helicase | enzymes that untwist the double helix at the replication forks | 13 | |
| 7600263612 | Single-strand binding proteins | bind to the unpaired DNA strands, keeping them from re-pairing | 14 | |
| 7600263613 | Topoisomerase | helps relieve strain from untwisting by breaking, swiveling, and rejoining DNA strands | 15 | |
| 7600263614 | Primer | RNA nucleotide chain produced at a DNA strand to begin replication; needed for DNA polymerase to begin adding DNA nucleotides during replication | 16 | |
| 7600263615 | Primase | synthesizes primer | 17 | |
| 7600263616 | DNA Polymerase | enzyme that catalyzes the synthesis of new DNA by adding nucleotides to a preexisting chain | 18 | |
| 7600263617 | Leading strand | receives 1 RNA primer and extends from the primer by a DNA polymerase; continuous replication in the 5' to 3' direction toward the replication fork | 19 | |
| 7600263618 | Lagging strand | DNA strand elongating away from the replication fork; requires several primers and produces new DNA in fragments | 20 | |
| 7600263619 | Okazaki Fragments | short series of segments on the lagging strand | 21 | |
| 7600263620 | DNA ligase | joins the sugar-phosphate backbones of all the Okazaki fragments into a continuous DNA strand | 22 | |
| 7600263622 | Nuclease | DNA cutting enzyme | 23 | |
| 7600263623 | Nucleotide excision repair | DNA repair system involving nuclease, DNA polymerase, and ligase | 24 | |
| 7600263624 | Telomeres | special nucleotide sequence at the ends of eukaryotic chromosomes | 25 | |
| 7600263625 | Chromatin | DNA and protein combined | 26 | |
| 7600263626 | Transcription | synthesis of RNA using information from DNA | 27 | |
| 7600263627 | mRNA | carries genetic message from the DNA to a protein-synthesizing machinery | 28 | |
| 7600263628 | Translation | synthesis of a polypeptide using the information in the mRNA; occurs at a ribosome | 29 | |
| 7600263630 | Template strand | The side of the DNA that provides a pattern for the sequence of nucleotides in an RNA transcript | 30 | |
| 7600263632 | RNA Polymerase | pries the 2 strands of DNA apart and joins together RNA nucleotides complementary to the DNA template strand; enzyme in charge of transcription | 31 | |
| 7600263633 | Promoter | sequence on the DNA template where RNA polymerase attaches and initiates transcription | 32 | |
| 7600263634 | Terminator | sequence that signals the end of transcription | 33 | |
| 7600263635 | Transcription unit | stretch of DNA downstream from the promoter that is transcribed into an RNA molecule | 34 | |
| 7600263637 | Transcription factors | collection of proteins that mediate the binding of RNA polymerase and the initiation of transcription in eukaryotes | 35 | |
| 7600263638 | Transcription initiation complex | whole complex of transcription factors and RNA polymerase II | 36 | |
| 7600263639 | TATA box | a sequence of nucleotides that is part of a eukaryotic promoter | 37 | |
| 7600263640 | RNA processing | stage in eukaryotes where both ends of the primary transcript are altered and splicing out of introns and joining of exons occurs | 38 | |
| 7600263641 | 5' cap | modified form of Guanine nucleotide added onto the 5' end during RNA processing | 39 | |
| 7600263642 | poly-A-tail | at the 3' end an enzyme adds 50-250 more adenine nucleotides to the mRNA to form this | 40 | |
| 7600263643 | RNA splicing | accomplished by spliceosomes | 41 | |
| 7600263644 | introns | intervening sequences; do not code for protein, are removed from the pre-mRNA | 42 | |
| 7600263645 | exons | coding sequences of the mRNA; get translated into amino acid sequences | 43 | |
| 7600263646 | spliceosome | complex made of proteins and snRNAs; remove introns from pre-mRNA and join together exons | 44 | |
| 7600263647 | ribozymes | RNA molecules that function as enzymes | 45 | |
| 7600263648 | Alternative RNA splicing | known to give rise to 2 or more different polypeptides depending on which segments are treated as exons during RNA processing | 46 | |
| 7600263649 | Domains | discrete structural and functional regions of proteins; usually coded for by different exons | 47 | |
| 7600263650 | tRNA | the translator; carries amino acids to their proper position on a mRNA | 48 | |
| 7600263651 | anticodon | particular nucleotide triplet on a tRNA that base-pairs to a specific mRNA codon during translation | 49 | |
| 7600263652 | Wobble | flexible base pairing at the third nucleotide position of a codon | 50 | |
| 7600263653 | rRNAs | make up ribosomes; catalyze reactions during translation | 51 | |
| 7600263654 | P site | the site on the large sub-unit of a ribosome that holds tRNA carrying the growing polypeptide chain when the A site is empty | 52 | |
| 7600263655 | A site | the site on the large sub-unit of a ribosome that receives the tRNA carrying the next amino acid to be added to a growing polypeptide | 53 | |
| 7600263656 | E site | where discharged tRNAs leave the ribosome | 54 | |
| 7600263657 | Signal peptide | targets a polypeptide being synthesized to the rough ER | 55 | |
| 7600263658 | SRP | recognizes a signal sequence on a polypeptide, connects to it, and then moves the polypeptide and its ribosome to the rough ER | 56 | |
| 7600263659 | Polyribosomes | enable a cell to make many copies of a polypeptide; multiple ribosomes translating the same mRNA | 57 | |
| 7600263660 | Mutations | responsible for the huge diversity of genes found among organisms; changes in DNA | 58 | |
| 7600263661 | Point mutations | changes in a single nucleotide pair of a gene | 59 | |
| 7600263662 | nucleotide-pair substitution | replacement of one nucleotide and its partner with another pair | 60 | |
| 7600263663 | silent mutation | no observable effect on the phenotype | 61 | |
| 7600263664 | missense mutation | if a substitution mutation changes only one amino acid of a protein | 62 | |
| 7600263665 | nonsense mutation | changes a codon for an amino acid into a stop codon | 63 | |
| 7600263666 | frameshift mutation | whenever the number of nucleotides inserted or deleted is not a multiple of three; can result in extensive missense or nonsense | 64 | |
| 7600622293 | histone | proteins that DNA wraps around to form nucleosomes of chromatin; | 65 | |
| 7600622294 | DNA polymerase I | removes the primer during replication and replaces it with DNA nucleotides on the lagging strand | 66 | |
| 7600641298 | Meselson and Stahl | their experiment supported the semi-conservative model of replication | 67 | |
| 7600645542 | nucleosome | a core of 8 histone proteins with DNA wrapped around it; beads on a string | 68 | |
| 7600663304 | pyrimidine nitrogenous bases | thymine, cytosine, uracil | 69 | |
| 7600671032 | telomerase | enzyme found in germ cells and tumors that maintains the length of telomeres | 70 | |
| 7600682798 | heterochromatin | highly condensed chromatin | 71 | |
| 7600685554 | euchromatin | chromatin that is not condensed and is available for transcription | 72 | |
| 7600695776 | one gene-one enzyme hypothesis | proposed by Beadle and Tatum as a result of their experiments with nutritional mutants of Neurospora | 73 | |
| 7600707495 | one gene-one polypeptide or RNA molecule | an improvement on Beadle and Tatum's hypothesis | 74 | |
| 7600723905 | gene expression | consists of transcription and translation | 75 | |
| 7600734881 | coupled transcription and translation | gene expression in prokaryotes; transcription and translation both happen at the same time in the cytoplasm | 76 | |
| 7600758601 | uncoupled transcription and translation | gene expression in eukaryotes; transcription occurs in the nucleus and translation happens in the cytoplasm; | 77 |
