bio test 2

  1. promoter
    a site where the transcription enzyme, RNA polymerase, attaches and initates transcription, determines which of the two strands of the DNA double helix is used as the template in trascription
  2. operator
    DNA control sequence, acts as a switch, determines whether RNA polymerase can attach to the promoter and start transcribing the gene
  3. operon
    cluster of genes with related functions, exist ONLY in prokaryotes
  4. repressor
    protein that turns off transcription, functions by binding to the operator and physically blocking the attachment of RNA polymerase to the promoter
  5. regulatory gene
    ocated outside the operon, codes for the repressor
  6. activators
    activatorsproteins that turn operons on by binding to DNA, make it easier for RNA polymerase to bind to the promoter
  7. histones
    crucial aspect of DNA packing, account for about half the mass of eukaryotic chromosomes --> small proteins grouped and wrapped around a DNA strand to form a nucleosome
  8. nucleosome
    consists of DNA wound around a protein core of 8 histone molecules
  9. transcription factors
    eukaryotic RNA polymerase requires the assistance of these proteins, such as activator proteins
  10. enhancer
    DNA control sequences, part of the first step in initiating gene transcription --> binding of activator proteins to these
  11. microRNA (miRNA)
    small RNA molecules that can bind to complementary sequences on mRNA molecules
  12. RNA interference (RNAi)
    procedure that involves injecting miRNa into a cell that can turn off expression of a gene with a sequence that matches the miRNA
  13. oncogene
    can cause cancer when present in a single copy in the cell
  14. proto-oncogene
    normal gene that has the potential to become an oncogene
  15. tumor suppressor genes
    proteins they encode help prevent uncontrolled cell growth/tumors
  16. restriction fragment length polymorphism (RFLP)
    variation in the lenght of a restriction fragment, produced when homologous DNA sequences containing SNPs are cut up with restriction fragments
  17. transcription
    the synthesis of RNA under the direction of DNA
  18. translation
    the synthesis of protein under the direction of RNA
  19. codons
    the genetic instructions for the amino acid sequence of a polypeptide chain are written in DNA and RNA as a series of nonoverlapping three-base "words"
  20. RNA polymerase
    transcription enzyme, links together the growing chain of RNA nucleotides during transcription, using a DNA strand as a template
  21. terminator
    that signals the end of the gene
  22. mRNA messenger RNA
    the type of ribonucleic acid that encodes the genetic information from DNA and conveys it to ribosomes, where the information is translated into amino acid sequences
  23. introns
    internal non-coding regions
  24. exons
    coding regions, the parts of a gene that are expressed
  25. RNA splicing
    the removal of introns and joining of exons in eukaryotic RNA, forming an mRNA molecule with a continuous coding sequence, occurs before mRNA leaves the nucleus
  26. transfer RNA (tRNA)
    a type of ribonucleic acid that functions as an interpreter in translation --> each molecule has an anticodon, picks up a specific amino acid, and conveys the amino acid to the appropriate codon on mRNA
  27. ribosomes
    structures in the cytoplasm that position mRNA and tRNA close together and catalyze the synthesis of polypeptides
  28. ribosomal RNA (rRNA
    a type of ribonucleic acid consisting of nucleotide monomers with a ribose suger and the nitrogenous bases A, C, G, U; usually single-stranded, fuctions in protein synthesis, gene regulation
  29. start codon
    specific codon that an mRNA molecule binds to where translation is to begin on the mRNA molecule
  30. stop codon
    in mRNA, one of the tree triplets (UAG, UAA, UGA) that signal gene translation to stop
  31. silent mutation
    a mutation in a gene that changes a codon to one that encodes for the same amino acid as the original codon --> the amino acid sequence of the resulting polypeptide is thus unchanged
  32. missense mutation
    a change in the nucleotide sequence of a gene that alters the amino acid seqeunce of the resulting polypeptide --> a codon is changed from encoding one amino acid to encoding a different amino acid
  33. nonsense mutation
    a change in the nucleotide sequence of a gene that converts an amino-acid-encoding codon to a stop codon --> results in a shortened polypeptide
  34. Transcription
    RNA Splicing
    Post-Translational Modification
    Steps in Gene Expression include what?
  35. induction
    Enzyme induction is a process in which a molecule induces the expression of an enzyme
  36. Repression
    Repression, in metabolism, a control mechanism in which a protein molecule, called a repressor, prevents the synthesis of an enzyme by binding to—and thereby impeding the action of—the deoxyribonucleic acid that controls the process by which the enzyme is synthesized
  37. allosteric
    allosteric regulation (or allosteric control) is the regulation of an enzyme by binding an effector molecule at a site other than the enzyme's active sit
  38. cAMP or Cyclic adenosine monophosphate
    2nd messenger of biological processes,
  39. TATA box
    DNA sequence that indicates where a genetic sequence can be read and decoded. It is a type of promoter sequence, which specifies to other molecules where transcription begins
  40. coactivator
    protein that increases gene expression by binding to an activator (transcription factor) which contains a DNA binding domain.
  41. Acetylation
    is the process where an acetyl functional group is transferred from one molecule (in this case, Acetyl-Coenzyme A) to anothe
  42. siRNA
  43. alternative splicing
    Alternative splicing, or differential splicing, is a regulated process during gene expression that results in a single gene coding for multiple proteins.
  44. Ubiquitin
    a compound found in living cells that plays a role in the degradation of defective and superfluous proteins. It is a single-chain polypeptide.
  45. Proteasome
    The main function of the this is to degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks peptide bonds.
  46. DNA Polymerase
    are enzymes that synthesize DNA molecules from deoxyribonucleotides, the building blocks of DNA.
  47. Helicase
    essential during DNA replication because they separate double-stranded DNA into single strands allowing each strand to be copied.
  48. Primase
    enzyme that creates a primer on a DNA strand by adding RNA nucleotides to the strand according to the DNA template sequenc
  49. Ligase
    an enzyme that brings about ligation of DNA or another substance.
  50. Topoisomerase
    enzymes that participate in the overwinding or underwinding of DNA.
  51. Gyrase
    enzyme within the class of topoisomerase that relieves strain while double-stranded DNA is being unwound by helicase
  52. Telomere
    distinctive structures found at the ends of our chromosomes
  53. Splicing
    involves the removal or "splicing out" of certain sequences referred to as intervening sequences, or introns
  54. Anti-Codon
    a sequence of three nucleotides forming a unit of genetic code in a transfer RNA molecule, corresponding to a complementary codon in messenger RNA.
  55. Mitosis
    a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
  56. meiosis
    type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells
  57. binary fission
    type of asexual reproduction in prokaryotic cells an adult cell splits in half creating two new cells
  58. G1
    stages of Cell Cycle
  59. interphase
    the resting phase between successive mitotic divisions of a cell, G1, S, and G2 phases happen in this cell phase
  60. prophase
    first stage of cell divisions, during which the chromosomes become visible as paired chromatids and the nuclear envelope disappears
  61. Prometaphase
    second phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells, nuclear envelope breaks down
  62. Metaphase
    3rd stage in mitosis the chromosomes, guided by the spindle fibers, line up in the middle of the dividing cell.
  63. Anaphase
    4th phase of mitosis,  spindle apparatus pulls the two chromatids of each chromosome apart and drags them toward opposite poles of the cell.
  64. Telophase
    fifth and final phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells.
  65. Cytokinesis
    physical process of cell division, which divides the cytoplasm of a parental cell into two daughter cells, happens at the end of mitosis or meiosis
  66. centrosome
    organelle that serves as a microtubule organizing center during division. It's duplicated during S phase, and the two copies move to opposite sides of the cell.
  67. mitotic spindle
    The spindle apparatus is the collective term for all the spindle fibers that form during mitosis or meiosis. These spindle fibers are responsible in moving and segregating the chromosomes during nuclear division.
  68. Homologous chromosomes
    one of the pair is from mother other father. The maternal and paternal chromosomes in a homologous pair have the same genes at the same loci, but possibly different alleles.
  69. Autosomes
    any chromosome that is not a sex chromosome
  70. gametes
    a mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.
  71. Zygote
    a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum.
  72. haploid
    (of a cell or nucleus) having a single set of unpaired chromosomes.(of an organism or part) composed of haploid cells.
  73. diploid
    ) containing two complete sets of chromosomes, one from each parent.
  74. Non-Disjunction
    the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei
  75. RNA-induced silencing complex, or RISC
    is a multiprotein complex, specifically a ribonucleoprotein, which incorporates one strand of a single-stranded RNA (ssRNA) fragment, such as microRNA (miRNA), or double-stranded small interfering RNA (siRNA).
Card Set
bio test 2