Patho Unit 1

  1. nucleotides
    • compose DNA
    • phosphoric acid, deoxyribose (5 carbon sugar), one of 4 nitrogen bases
  2. nitrogenous bases of DNA
    • pyrimidine bases- thymine & cytosine
    • purine bases- adenine & guanine
  3. somatic cell
    • all cells other than gametes
    • 23 pairs chromosomes
  4. chromatin
    coiled structure of DNA
  5. nucleosome
    complex of DNA with histone
  6. codon
    triplet code for transmitting protein synthesis
  7. DNA to RNA substitution
    thyamine in DNA replaced by uracil in RNA
  8. stop codes
    signal end of protein molecule
  9. endonucleases
    recognize DNA distortions & remove
  10. haplotype
    • variation on gene sequence
    • human variation <0.1%
  11. mitochondrial DNA
    • inherited from mother
    • 37 genes (24 for translation & 13 for oxidative metabolism)
  12. messenger RNA
    carries instruction for protein synthesis from DNA into cytoplasm
  13. transfer RNA
    reads instructions & delivers amino acids to ribosome
  14. ribosomal RNA
    translates instructions & provides machinery for protein synthesis
  15. promoter region
    area in DNA where RNA synthesis begins
  16. molecular chaperones
    proteins that fold proteins into forms that can be transported to site to carry out function
  17. denatured proteins
    • incorrectly folded proteins (failure of chaperoning mechanism)
    • stick together & form inclusion bodies
  18. gene expression
    degree to which gene is active
  19. gene induction
    process where gene expression is increased
  20. gene repression
    regulatory gene acts to reduce or prevent gene expression
  21. transcription factors
    proteins used to initiate & regulate transcription
  22. homologous chromosomes
    maternal & paternal chromosomes
  23. autosomes
    22 chromosomes that are alike in both males & females
  24. Barr body
    inactive chromatin mass from inactive x chromosome
  25. mitosis
    • non-germ cells
    • replace cells that have limited life span
  26. meiosis
    • replicates germ cells
    • only once in cell line
  27. crossing over
    • interchange of chromatid segments
    • new combinations of genes
  28. cytogenetics
    study of structure & characteristics of chromosomes
  29. centromere
    • area where chromosome comes together
    • metacentric- center
    • submetacentric- arms different lenght
    • acrocentric- near one end
  30. telomere
    • special sequences at end of DNA
    • allow end of molecule to be replicated completely
  31. genotype
    genetic information stored in base triplet code
  32. phenotype
    recognizable traits, physical or biochemical, associated with specific genotype
  33. expressivity
    manner that gene is expressed in phenotype
  34. penetrance
    ability of gene to express function
  35. locus
    position of gene on chromosome
  36. allelle
    alternate form of gene at same locus
  37. polygenic inheritance
    multiple genes at different loci with each gene exerting small additive effect on determining a trait
  38. multifactorial inheritance
    • multiple alleles affect outcome
    • can be influenced by environments effects
  39. epistasis
    one gene masks phenotypic effects of nonallele gene
  40. multiple allele
    more than one allele affect same trait
  41. complimentary gene
    each gene mutually dependent on the other
  42. collaborative gene
    2 different genes influence same trait interact to produce phenotype neither could do alone
  43. genomic imprinting
    parental genomes do not always contribute equally to development
  44. pedigree
    graphic method for tracing family history of inherited trait
  45. linkage studies
    the closer together genes are on chromosome the more likely they will appear together and not affected by crossing over
  46. somatic cell hybridization studies
    • fusion of human somatic cells with a different species to yeild chromosomes of both
    • obtain cells w/ different partial combinations of human chromosomes
  47. in situ hybridization studies
    • use of specific sequences of DNA or RNA to locate genes that do not express themselves in cell culture
    • chemicaly tagged sequences used as probes to detect gene location
  48. nucleotide polymorphisms
    sites in DNA sequence where individuals differ at a single base
  49. recombinant DNA
    combination of DNA molecules not found together in nature
  50. gene cloning
    cutting DNA apart, modifying & reassembling fragments, and reproducing copies
  51. RNA interference
    • small pieces of RNA suppress gene expression
    • use RNA to stop genes from making disease
Card Set
Patho Unit 1
chapter 5