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DNA, RNA, and PS
DNA, RNA and Protein Synthesis by Elaina Huerta
| Term | Definition |
|---|---|
| Double helix | The shape of the DNA molecule; consists of TWO nucleotide chains that wrap around each other to form a double spiral. |
| Nucleotides | Monomers that make up DNA and RNA; consists of a nitrogen base (A, C, T, U, or G), a sugar and a phosphate molecule. |
| Adenine (A) | Nitrogenous base found in DNA and RNA; pairs with T or U. |
| Guanine (G) | Nitrogenous base found in DNA and RNA; pairs with C. |
| Cytosine (C) | Nitrogenous base found in DNA and RNA; pairs with G. |
| Thymine (T) | Nitrogenous base found in DNA and RNA; pairs with A. |
| Uracil (U) | Nitrogenous base found in RNA only; pairs with T. |
| Purines | Nitrogenous bases that have a double ring of carbon and nitrogen atoms; Adenine and Guanine. |
| Pyrimidines | Nitrogenous bases that have a single ring of carbon and nitrogen atoms; Cytosine, Thymine, and Uracil. |
| Complementary | Matching, as in complementary bases: A, matches T or U; C matches G. |
| Semi-conservative replication | Specific type of replication in DNA that results in two, double stranded DNA molecules. Each new molecule has half of the original strand, and half that is a complimentary (newly built) strand. |
| Hydrogen bonds | Weak attractions between molecules; hydrogen bonds hold the rungs of the DNA ladder together , but can be easily broken and reformed again. |
| Helicase | Enzyme that unwinds and unzips DNA. |
| Ligase | Enzyme that creates bonds between sugars and phosphates in a growing DNA or RNA strand as it is being built. |
| DNA polymerase | Enzymes that can bind to a single (unwound and separated) DNA strand, read it, and synthesize a new strand of complementary DNA; some are able to proofread their work. |
| Protein synthesis | The formation of proteins using information coded on DNA and carried out by RNA in the ribosome. |
| messenger RNA (or mRNA) | A single uncoiled strand of RNA that transmits information from DNA to the ribosomes during protein synthesis. |
| Transfer RNA (or tRNA) | A single folded strand of RNA that bonds with and carries a specific amino acid, |
| Ribosomal RNA (rRNA) | A globular form of RNA that is the major constituent of the ribosomes. |
| transcription | The process of forming a mRNA strand from a DNA strand in the nucleus. |
| RNA polymerase | Enzyme used in protein synthesis (translation) read a DNA gene and compose a complementary mRNA strand. |
| Codon | A 3-nucleotide mRNA sequence that codes for one specific amino acid. |
| Start codon | A coding sequence that signals the start of the gene to be transcribed. |
| Stop codon | A coding sequence that signals the end of the gene to be transcribed. |
| Translation | The formation of proteins in the cytoplasm using information coded on mRNA and carried out by the ribosome. |
| Anticodon | One end of a tRNA molecule that contains a set of three nucleotides that will compliment codons on the mRNA during translation; has a site for a specific amino acid on the opposite end. |
| Mutations | A mutation is any change in the DNA's letter (nitrogenous base) sequence. |
| Point mutation | A change in a single nitrogen base in DNA; may or may not cause a change in the amino acid depending on position of letter changed. |
| Frameshift mutation | Addition or deletion of a nitrogen base, causing a shift in codons so that the gene sequence is nonsense. |
| Mutagen | Anything that causes a mutation. |
| Human genome project | An international effort to determine all the base pairs of the human genome. |
| DNA fingerprinting | Scientists utilize the genetic "fingerprints" where DNA is broken into pieces and examined for patterns. |
| Gene therapy | Treats a genetic disorder by introducing a gene into a cell or by correcting a defect in a cell's genome. |
| Genetic engineering | Used to identify genes for specific traits or to transfer genes from one organism to another organism; involves the making of recombinant DNA in a lab. |
| Recombinant DNA | A combination of DNA from two or more sources. |
| Genetically modified organisms (GMOs) | Any organism whose DNA has been modified by genetic engineering |
| Cloning | Refers to any of a number of biotechnologies that aim to reproduce a genetic copy of an entire organism. |