Biotechnology and Genetics terms starting with T

196 terms

  1. Toxicogenomics The study of how genomes respond to environmental stressors or toxicants. Combines genome-wide mRNA expression profiling with protein expression patterns…
  2. toxin (TOK-sin) A poison produced by certain animals, plants, or bacteria.
  3. tracer A substance (such as a radioisotope) used in imaging procedures.
  4. tracheid An elongated, tapering xylem cell, with lignified pitted walls, adapted for solute conduction and physical support.
  5. Traditional breeding Modification of plants and animals through selective breeding. Practices used in traditional plant breeding may include aspects of biotechnology such as…
  6. Trait See Phenotype.
  7. trans configuration See: repulsion.
  8. trans heterozygote A double heterozygote that contains two mutations arranged in the trans configuration.
  9. trans test See: complementation test.
  10. trans-acting 1. A term describing substances that are diffusable and that can affect spatially separated entities within cells. 2. A genetic element (e.g.
  11. trans-acting factor Any of the multiple ancillary DNA -binding proteins that interact with the cis-regulatory DNA sequences to control gene expression.
  12. Transaminase An enzyme that catalyzes chemical reactions in the body in which an amino group is transferred from a donor molecule to a recipient molecule.
  13. Transcapsidation The partial of full coating of the nucleic acid of one virus with a coat protein of a differing virus. See Coat protein.
  14. Transcript a written copy of spoken or recorded material which is the official or legal copy of a court hearing, also called a court reporter’s transcript.
  15. Transcription In biology, the process by which a cell makes an RNA copy of a sequence of DNA that is a gene.
  16. Transcription factor A protein that regulates the transcription of genes.
  17. Transcription factors Specialized proteins that bind to specific sites on DNA and turn on or turn off the expression of different sets of genes.
  18. transcription unit A segment of DNA that contains signals for the initiation and termination of transcription, and is transcribed into one RNA molecule.
  19. transcriptional anti-terminator A protein that prevents RNA polymerase from terminating transcription at specific transcription termination sequences.
  20. transcriptional roadblock A DNA -binding protein which affects the rate at which RNA polymerases transcribe genes.
  21. Transcriptome The full complement of activated genes, mRNAs, or transcripts in a particular tissue at a particular time
  22. Transdifferentiation The ability of a particular cell of one tissue, organ or system, including stem or progenitor cells, to differentiate into a cell type characteristic of…
  23. Transducing phage See Transduction.
  24. Transduction The transfer of DNA sequences from one bacterium to another via lysogenic infection by a bacteriophage (transducing phage).
  25. Transfection The uptake and expression of a foreign DNA sequence by cultured eukaryotic cells.
  26. Transfer DNA See T\-DNA.
  27. transfer RNA See: tRNA.
  28. Transfer RNA (tRNA) See tRNA.
  29. transferase A class of enzymes that catalyses the transfer of a group of atoms from one molecule to another.
  30. Transformant In prokaryotes, a cell that has been ge- netically altered through the uptake of foreign DNA.
  31. transformation (TRANZ-for-MAY-shun) In medicine, the change that a normal cell undergoes as it becomes malignant.
  32. Transformation efficiency The number of bacterial cells that uptake and express plasmid DNA divided by the mass of plasmid used (in transformants/microgram). (See Transformation.)
  33. transformation efficiency or frequency The fraction of a cell population that takes up and integrates the introduced transgene; expressed as the number of transformed cells recovered divided by…
  34. Transforming oncogene A gene that upon transfection converts a previously immortalized cell to the malignant phenotype. (See Oncogene.)
  35. Transgene See Transgenic.
  36. transgenesis The introduction of a gene or genes into animal or plant cells, which leads to the transmission of the input gene (transgene ) to successive generations.
  37. Transgenic An organism in which a foreign DNA gene (a transgene) is incorporated into its genome early in de- velopment.
  38. Transgenic animal Genetically enginnered animal or offspring of genetically engineered animals. The transgenic animal usually contains material from at lease one unrelated…
  39. Transgenic plant Genetically engineered plant or offspring of genetically engineered plants. The transgenic plant usually contains material from at least one unrelated…
  40. transgressive variation The appearance, in a segregating generation, of individuals showing expression of a trait outside the extremes defined by the parent of the cross that was…
  41. transient expression Short-term activity of a transgene following its introduction into. Transient expression usually implies non-integration of the transgene into the.
  42. transition These are where one type of bottom material or structure changes to another, for instance, a rock pile to solid rock, or sand to gravel.
  43. transition stage The period between juvenile and reproductive stages of growth.
  44. Transition-state intermediate In a chemical reaction, an unstable and high-energy configuration assumed by reactants on the way to making products.
  45. Translation The process of converting the genetic infor- mation of an mRNA on ribosomes into a polypeptide.
  46. translational initiation signal See: initiation codon.
  47. translational start codon See: initiation codon.
  48. translational stop signal See: termination codon.
  49. Translocation (TRANZ-loh-KAY-shun) A genetic change in which a piece of one chromosome breaks off and attaches to another chromosome.
  50. Transplantation (tranz-plan-TAY-shun) The replacement of tissue with tissue from the person's own body or from another person.
  51. Transplantation biology The science that studies the transplantation of organs and cells. Transplantation biologists investigate scientific questions to understand why foreign…
  52. Transposable element A class of DNA sequences that can move from one chromosomal site to another.
  53. Transposable genetic element See Transposon.
  54. transposase An enzyme encoded by a that catalyses the movement of a DNA sequence to a different site in a DNA molecule.
  55. transposition The movement of a DNA segment within the genome of an organism.
  56. transposon Synonym of transposable genetic element.
  57. Transposon (transposable, or movable genetic element) A relatively small DNA segment that has the ability to move from one chromosomal position to another.
  58. transposon tagging A method of gene isolation that exploits the disruption of normal gene expression that is the result of an insertion of a transposon within, or close to…
  59. transversion The substitution in DNA or RNA of one purine by a pyrimidine or vice versa. See: transition, base substitution.
  60. tri-hybrid The hybrid offspring of a cross between parents carrying contrasting alleles at three loci.
  61. tribrid protein A fusion protein that has three segments, each encoded by parts of different genes.
  62. trichome A short filament of cells, resulting in a hair-like structure.
  63. trinucleotide repeat Tandem repeats of three nucleotides that are present in many genes. Commonly trinucleotide repeats have undergone variable expansion in copy number…
  64. tripartite mating A process in which conjugation is used to transfer a plasmid vector to a when the plasmid vector is not self-mobilizable.
  65. triplet A sequential group of three nucleotides in DNA or RNA. See: codon.
  66. triploid A cell, tissue or organism containing three times the haploid number of chromosomes.
  67. trisomic (adj.) See: trisomy.
  68. trisomy The presence in a diploid cell or organism of an extra chromosome of one homologue (chromosome formula: 2n + 1). See: disomy; monosomic.
  69. triticale The hybrid man-made species formed by the crossing of tetraploid or hexaploid wheat with diploid rye.
  70. tRNA Abbreviation for transfer RNA. Small RNA molecules that transfer amino acids to the ribosome during protein synthesis.
  71. tRNA (transfer RNA) The class of small RNA molecules that transfer amino acids to the ribosome during protein synthesis. See Transfer RNA.
  72. Trophectoderm a term used to refer to trophoblast cells in mice.
  73. Trophoblast (TROH-foh-BLAST) A thin layer of cells that helps a developing embryo attach to the wall of the uterus, protects the embryo, and forms a part of the…
  74. tropism Plant response to an external stimulus, resulting in the bending/turning of stem or root growth.
  75. true-to-type Conforming to the phenotype of the breed/variety.
  76. Trypsin A proteolytic enzyme that hydrolyzes peptide bonds on the carboxyl side of the amino acids arginine and lysine.
  77. trypsin inhibitor Substances inactivating trypsin, typically found in of certain plants, where they are thought to have evolved as anti-feedant agents against insect…
  78. TSCA The Toxic Substances Control Act. See Environmental Protection Agency.
  79. TTP Abbreviation for thymidine 5'-triphosphate. TTP is required for DNA synthesis since it is a direct precursor molecule. See: thymidine, thymidylic acid.
  80. tubulin (TOO-byuh-lin) One of a group of proteins found in high levels in the cell cytoplasm (fluid inside a cell but outside the cell's nucleus).
  81. tumble tube A glass tube mainly used in vitro to agitate and consequently aerate suspension cultures.
  82. Tumor DNA See T\-DNA.
  83. tumor suppressor gene (TOO-mer suh-PREH-ser jeen) A type of gene that makes a protein called a tumor suppressor protein that helps control cell growth.
  84. Tumor virus A virus capable of transforming a cell to a malignant phenotype. (See Virus.)
  85. Tumor-inducing plasmid See Ti plasmid.
  86. tumour virus A virus capable of transforming a cell to a malignant phenotype.
  87. tumour-inducing plasmid See: Ti plasmid.
  88. tunica The outer one- to four-cell layer region of the apical meristem, where cell division is anticlinal, i.e. perpendicular to the surface.
  89. turbidostat An open continuous culture in which a pre-selected biomass density is uniformly maintained by automatic removal of excess cells.
  90. turgid Swollen, distended; referring to a cell that is extended as a result of adequate water uptake. Loss of turgidity in plant cells is a sign of water deficit.
  91. turgor potential See: pressure potential.
  92. turgor pressure The pressure within a cell resulting from the absorption of water into the vacuole and the imbibition of water by the protoplasm.
  93. turion An underground bud or shoot from which an aerial stem arises. See: sucker.
  94. twin One of two individuals originating from the same zygote.
  95. Twinning Development of monozygotic twins, that is, when a very early embryo separates into two pieces, each of which continues development, so that two embryos…
  96. Type-1A diabetes A form of insulin dependent diabetes, usually becoming evident in childhood, resulting from an autoimmune reaction that destroys the pancreatic beta…