Campbell Biology Chapter 17 Flashcards
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| 6895213247 | A Site | one of a ribosome's three binding sites for tRNA during translation; the A site holds the tRNA carrying the next amino acid to be added to the polypeptide chain. (A stands for aminoacyl tRNA.) |  | 0 |
| 6895213248 | Alternative RNA Splicing | a type of eukaryotic gene regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns |  | 1 |
| 6895213249 | Anticodon | a nucleotide triplet at one end of a tRNA molecule that base-pairs with a particular complementary codon on an mRNA molecule |  | 2 |
| 6895213250 | 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 |  | 3 |
| 6895213251 | Exon | a sequence within a primary transcript that remains in the RNA after RNA processing; also refers to the region of DNA from which this sequence was transcribed |  | 4 |
| 6895213252 | Frameshift Mutation | A mutation occurring when nucleotides are inserted in or deleted from a gene and the number inserted or deleted is not a multiple of three, resulting in the improper grouping of the subsequent nucleotides into codons |  | 5 |
| 6895213253 | Gene Expression | the process by which information encoded in DNA directs the synthesis of proteins or, in some cases, RNAs that are not translated into proteins and instead function as RNAs |  | 6 |
| 6895213254 | Insertion | a mutation involving the addition of one or more nucleotide pairs to a gene | 7 | |
| 6895213255 | Intron | a noncoding, intervening sequence within a primary transcript that is removed from the transcript during RNA processing; also refers to the region of DNA from which this sequence was transcribed | | 8 |
| 6895213256 | Messenger RNA (mRNA) | a type of RNA, synthesized using a DNA template, that attaches to ribosomes in the cytoplasm and specifies the primary structure of a protein. (In eukaryotes, the primary RNA transcript must undergo RNA processing to become mRNA.) |  | 9 |
| 6895213257 | Missense Mutation | a nucleotide-pair substitution that results in a codon that codes for a different amino acid |  | 10 |
| 6895213258 | Mutagen | a chemical or physical agent that interacts with DNA and can cause a mutation (Ex: UV light, tanning bed) | 11 | |
| 6895213259 | Mutation | a change in the nucleotide sequence of an organism's DNA or in the DNA or RNA of a virus |  | 12 |
| 6895213260 | Nonsense Mutation | a mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein |  | 13 |
| 6895213261 | Nucleotide-Pair Substitution | a type of point mutation in which one nucleotide in a DNA strand and its partner in the complementary strand are replaced by another pair of nucleotides |  | 14 |
| 6895213262 | P Site | one of a ribosome's three binding sites for tRNA during translation; the P site holds the tRNA carrying the growing polypeptide chain. (P stands for peptidyl tRNA.) |  | 15 |
| 6895213263 | Point Mutation | a change in a single nucleotide pair of a gene |  | 16 |
| 6895213264 | Poly-A Tail | a sequence of 50-250 adenine nucleotides added onto the 3′ end of a pre-mRNA molecule |  | 17 |
| 6895213265 | Polyribosome (Polysome) | a group of several ribosomes attached to, and translating, the same messenger RNA molecule The whole picture is a polyribosome |  | 18 |
| 6895213266 | Primary Transcript | an initial RNA transcript from any gene; also called pre-mRNA when transcribed from a protein-coding gene. This is what you get right after the slicing occurs. | 19 | |
| 6895213267 | Promoter | a specific nucleotide sequence in the DNA of a gene that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place |  | 20 |
| 6895213268 | Reading Frame | on an mRNA, the triplet grouping of ribonucleotides used by the translation machinery during polypeptide synthesis |  | 21 |
| 6895213269 | Ribosomal RNA (rRNA) | RNA molecules that, together with proteins, make up ribosomes; the most abundant type of RNA | 22 | |
| 6895213270 | Ribosome | a complex of rRNA and protein molecules that functions as a site of protein synthesis in the cytoplasm; consists of a large and a small subunit. In eukaryotic cells, each subunit is assembled in the nucleolus; see also nucleolus |  | 23 |
| 6895213271 | RNA Processing | modification of RNA primary transcripts, including splicing out of introns, joining together of exons, and alteration of the 5′ and 3′ ends | 24 | |
| 6895213272 | RNA Splicing | after synthesis of a eukaryotic primary RNA transcript, the removal of portions of the transcript (introns) that will not be included in the mRNA and the joining together of the remaining portions (exons) |  | 25 |
| 6895213273 | Signal Peptide | a sequence of about 20 amino acids at or near the leading (amino) end of a polypeptide that targets it to the endoplasmic reticulum or other organelles in a eukaryotic cell |  | 26 |
| 6895213274 | Signal-Recognition Particle (SRP) | a protein-RNA complex that recognizes a signal peptide as it emerges from a ribosome and helps direct the ribosome to the endoplasmic reticulum (ER) by binding to a receptor protein on the ER | | 27 |
| 6895213275 | Silent Mutation | a nucleotide-pair substitution that has no observable effect on the phenotype; for example, within a gene, a mutation that results in a codon that codes for the same amino acid |  | 28 |
| 6895213276 | Start Point | in transcription, the nucleotide position on the promoter where RNA polymerase begins synthesis of RNA |  | 29 |
| 6895213277 | TATA Box | a DNA sequence in eukaryotic promoters crucial in forming the transcription initiation complex |  | 30 |
| 6895213278 | Template Strand | the DNA strand that provides the pattern, or template, for ordering, by complementary base pairing, the sequence of nucleotides in an RNA transcript |  | 31 |
| 6895213279 | Terminator | In bacteria, a sequence of nucleotides in DNA that marks the end of a gene and signals RNA polymerase to release the newly made RNA molecule and detach from the DNA. Same as STOP but for Bacteria |  | 32 |
| 6895213280 | Transcription | the synthesis of RNA using a DNA |  | 33 |
| 6895213281 | Transcription Factor | a regulatory protein that binds to DNA and affects transcription of specific genes |  | 34 |
| 6895213282 | Transcription Unit | a region of DNA that is transcribed into an RNA molecule |  | 35 |
| 6895213283 | Transfer RNA (tRNA) | an RNA molecule that functions as a translator between nucleic acid and protein languages by carrying specific amino acids to the ribosome, where they recognize the appropriate codons in the mRNA | 36 | |
| 6895213284 | 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 |  | 37 |
| 6895213285 | Triplet Code | a genetic information system in which sets of three-nucleotide-long words specify the amino acids for polypeptide chains |  | 38 |
| 6895213286 | Wobble | flexibility in the base-pairing rules in which the nucleotide at the 5′ end of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position (3′ end) of a codon |  | 39 |