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| the only type of RNA that carries protein-building information to ribosomes. |
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| type of RNA that becomes complexed with proteins to form ribosomes, and some catalyze te assembly of polypeptide chains. |
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| type of RNA molecule that delivers amino acids to the ribosomes. (its anticodon pairs with an mRNA codon during transation.) |
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| when associating with RNA, uracil takes the place of thymine, and can, too, pair with adenine. |
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| an enzyme that adds ribonucleotides one at a time to the end of a growing RNA strand. |
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| the first step in protein synthesis. In this process, an RNA strand is assembled from nucleotides using a gene region in DNA as a template. |
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| second stage of protein synthesis. At ribosomes, information that's encoded in an mRNA transcript guides the synthesis of a new polypeptide chain from amino acid. |
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| acts as a "start" signal; a base sequence in DNA to which RNA polymerases bind and prepare for transcription. The gene's base sequence is used as a template for covalently bonding ribonucleotides together. When it reaches a sequence that signals "the end" of the gene region, the new RNA is released as a free transcript. |
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| exons are protein-coding base sequences that are interrupted by noncoding sequences, called introns. (Introns are snipped out before the transcript reaches the cytoplasm.) |
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| the base triplets in mRNA, (bases are "read" three at a time.) |
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| a ribonucleotide base triplet that can base-pair with complementary codons in an mRNA transcript. (There are 64 codons.) *A-T and G-C* |
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| Most cases happen while DNA is being replicated. Mutation does not always neccessarily mean negative outcomes, however when related with genes they are usually refered to as not beneficial. TMutation can occur when one base gets substituted for another in the nucleotide sequence. In other cases, an extra base is inserted or one is lost. These small changes to the sequence of a DNA molecule can greatly alter the message that becomes encoded in the mRNA. |
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| breaks down chromosomes into pieces. Exposure to this radiation is known to cause some types of mutation because it damages the DNA directly, penetratin living tissues and leaving behind a long trail of destructive free radicals. |
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| excites electrons to a higher energy level. DNA absorbs one form, (UV light.) Exposing your skin to these rays causes damage and dimer formation of the skin cells. |
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| transfer charged methyl or ethyl groups to reactive sites in DNA. At these sites, DNA is more vulnerable to mistakes in base-pairinf and to mutation. |
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| a deadly protein with two polypeptide chains; found in castor oil plants, a done o ricin as small as a grain of salt can kill you, because it inactivates ribosomes (the protein builders for all cells.) |
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| process to translate DNA into protein |
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Definition
| DNA--->(transcription) RNA---> (translation) Protein |
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| by this, one gene can specify two or more proteins that differ slightly in form and function. It may occur in half or all genes of the human genome. |
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| the set of 64 different codons, (and has been highly conserevd over time.) |
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| are built on ribosomes, each consisting of a large and small subunit made of tRNA and proteins |
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| the last stage o translation; the mRNA's stop codon enters the ribosome, (no tRNA has a corresponding anitcodon,) and proteins, called release factors, bind to the ribosome. Binding is what triggers the enzyme activity that detaches the mRNA and the polypetide chain from the ribosome. |
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| (or transposable elements,) are what mutations arise from, and can jump around the genome. When they lnd, they alter the timing or duration of its activity, or block it entirely. |
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