Genetics vocab ch. 9

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Genetics vocab ch. 9
2011-04-10 21:45:49
Genetics vocab

Chapter 9 vocab
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  1. Alkaptonuria
    an autosomal recessive trait with altered metabolism of homogentisic acid. Affected individuals do not produce the enzyme needed to metabolize this acid, and their urine turns black
  2. Amino Acid
    One of the 20 subunits of proteins. Each contains an amino group, a carboxyl group, and an R group
  3. Codon
    Triplets of nucleotides in mRNA that encolde the information for a specific amino acid in a protein
  4. Stop Codon
    A codon in mRNA that signals the end of translation. UAA, UAG, and UGA are stop codons
  5. Start Codon
    A codon present in mRNA that signals the location for translation to begin. AUG
  6. pre-messenger RNA (pre-mRNA)
    The transcript made from the DNA template that is processed and modified to form messenger RNA
  7. Transcription
    Transfer of genetic information from the base sequence of DNA to the base sequence of an mRNA molecule into the linear sequence of amino acids in a protein
  8. Introns
    DNA sequences present in some genes that are transcribed but are removed during processing and therefore are not present in mature mRNA
  9. Exons
    DNA sequences that are transcribed joined to other exons during mRNA processing, and translated into the amino acid sequence of a protein
  10. cap
    A modified base (guanine nucleotide) attached to the 5' end of eukaryotic mRNA molecules
  11. Poly-A tail
    A series of A nucleotides added to the 3' end of mRNA molecules
  12. Amino Group
    A chemical group NH2 found in amino acids and at one end of a polypeptide chain
  13. Carboxyl Group
    a chemical group COOH found in amino acids and at one end of a polypeptide chain
  14. R group
    each amino acid has a different side chain, called an __________, it can be positively or negatively charged of neutral
  15. Polypeptide
    a molecule made of amino acids joined together by peptide bonds
  16. N-terminus
    the end of a polypeptide of protein that has a free carboxyl group
  17. C-terminus
    The end of a polypeptide or protein that has a free carboxyl group
  18. Ribosomes
    Cytoplasmic particle composed of tow subunits that are the site of protein synthesis
  19. Ribosomal RNA
    RNA molecules that are part of the Ribosome
  20. Transfer RNA
    A small RNA molecule that contains a binding site for a specific type of amino acid and has a three-base segment known as an anticodon that recognizes a specific base sequence in messenger RNA
  21. Anticodon
    A group of three nucleotides in a tRNA molecule that pairs with a complementary sequence (known as a codon) in an mRNA moleucle
  22. Initiation complex
    formed by the combination of mRNA, tRNA, and the small ribosome subunit. The firs step in translation
  23. Peptide bond
    A covalent chemical link between the carboxyl group of one amino acid and the amino group of another amino acid
  24. Polysomes
    a mRNA molecule with several ribosomes attached
  25. Primary Structure
    The amino acid sequence in a polypeptide chain
  26. Secondary structure
    The pleated or helical structure in a protein molecule generation by the formation of bonds between amino acids
  27. Tertiary structure
    the three dimensional structure of a protein molecule brought about by folding on itself
  28. Quaternary Structure
    the structure formed by the interaction of two or more polypeptide chains in a protein
  29. Prion
    A protein folded into an infectious conformation that is the cause of several disorders, including Creutzfelt-Jakob disease and mad-cow disease
  30. Mad cow disease
    a prion disease of cattle, also known as bocine spongiform encephalopathy, or BSE
  31. Chromatin remodeling
    The process of chemical changes to the DNA and histones that activate and inactivate gene expression
  32. RNA interference (RNAi)
    A mechanism of gene regulation that controls the amounts of mRNA available for translation