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A-B-C-D-E-F-G-H-I-J-K-L-M-N-O-P-Q-R-S-T-U-V-W-X-Y-Z
- T cell
- Lymphocyte that matures within the thymus. The cells active in cell-mediated immunity are T cells. [Discussion] [CD4+ subset] [CD8+ subset] [Helper subsets (Th1 and Th2)]
- TACO
- tryptophan-aspartate coat protein
- Taiga
- The northern coniferous forest.
- TAP
- Transporter associated with antigen processing [More]
- Taste
- in humans
- Taxis
- Automatic locomotion of a motile organism in a direction determined by the direction from which the stimulus strikes the organism.
- Taxol
- Taxonomy
- Classification of organisms.
- TCDD
- [dioxin]
- TCR
- T-cell receptor for antigen. [More] [gene segments]
- Telomerase
- Telomeres
- Tendon
- Teratogen
- A substance that causes birth defects.
- Teratoma
- Tertiary structure
- [Protein]
- tesla
- Unit of magnetic field strength. [More]
- Test cross
- Testosterone
- Tetanus
- Sustained maximal contraction of a muscle. [More]
- Tetracycline antibiotics
- Tetrad
- (1) The duplicated homologous chromosomes held together by chiasmata prior to anaphase I of meiosis. Each tetrad contains four chromatids. [More] (2) The four products of meiosis kept together like the four spores in the ascus of budding yeast.
- Thalamus
- THC
- delta-9-tetrahydrocannabinol
- Thiamine
- vitamin B1
- Thick (and thin) filaments
- of muscle
- Thoracic duct
- Threonine
- [structure]
- Threshold
- Minimum intensity of a stimulus to which something responds. [of excitable cells]
- Thrombin
- Enzyme that converts fibrinogen to fibrin. [More]
- Thrombocytopenic purpura, immune
- Thrombopoietin
- Liver hormone that stimulates platelet production. [More]
- Thylakoid
- A pair of chlorophyll-containing membranes that form disklike structures within chloroplasts. Stacks of thylakoids are called grana.[More]
- Thymidine kinase
- [More]
- Thymine
- [structure]
- Thyroid-stimulating hormone (TSH)
- Thyrotoxicosis
- Graves' disease
- Thyrotropin-releasing hormone (TRH)
- Thyroxine
- Tight Junctions
- Tissue
- Association of cells bound together by cell walls (plants) or extracellular matrix (animals) that performs particular functions.
- Tissue typing
- to determine histocompatibility
- Tissue plasminogen activator (TPA)
- Titin
- [Size]
- Tocopherol
- vitamin E
- Tonus
- Sustained, partial contraction of a muscle. [More]
- Torr
- A unit of pressure equal to that exerted by a column of mercury 1 mm high; hence equal to the unit mm Hg.
- Total fertility rate (TFR)
- The average number of children in a family.
- Toxin
- Metabolic product (usually a protein) of an organism that is poisonous to another organism.
- Toxoid
- Toxin treated to destroy its poisonous quality but leaves it capable of stimulating the production of antibodies that will be able to bind to the unaltered toxin. The DTP vaccine contains both diphtheria and tetanus toxoid.
- Tracheophyte
- A plant with a vascular system of xylem and phloem. Includes all plants except mosses and their relatives.
- Tranquilizers
- Trans fatty acids
- Transcription
- The synthesis of a sequence of ribonucleotides complementary to the sequence of deoxyribonucleotides in a molecule of DNA. [Discussion]
- Transcription factor
- A protein needed to initiate the transcription of a gene. Some transcription factors bind to specific sequences of DNA (promoters and enhancers); others bind to each other; many bind both to DNA as well as to other transcription factors.
- [selector genes]
[glucocorticoid receptor][jun,fos,myc][E2F]
- Transducin
- Transformation
- The modification of the genotype of a cell by introduction of DNA from another source. Also, the conversion of a normal cell into a cancerous one.[Discussion]
- Transgenic
- An animal or plant that has been deliberately transformed with a foreign gene and is able to pass that gene on to future generations in its gametes.[making transgenic mice] [making transgenic plants]
- Transitions
- [mutation]
- Translation
- The synthesis of a polypeptide in accordance with the genetic information encoded in a molecule of messenger RNA (mRNA).[Discussion]
- Translocation
- (1) Transfer of a piece of one chromosome to another, nonhomologous, chromosome. [More]. [Example: Philadelphia chromosome]
- (2) Transport of proteins in (and out) of the endoplasmic reticulum.
- (3) Transport of materials from one part of a plant to another.
- Transmembrane protein
- Protein that passes one or more times through the lipid bilayer of a cell membrane. [color schematic (48K)]
- Transplantation
- discussion of organ and tissue transplantation
- Transpiration
- Evaporation of water from plants.[More]
- Transport vesicle
- Membrane-enclosed structure that shuttles soluble as well as integral membrane proteins to various destinations within the cell. [More]
- Tranversions
- [mutation]
- Tricyclic antidepressants
- Triglyceride
- Glycerol carrying three molecules of fatty acid. A fat. [More]
- Trihalomethanes (THMs)
- [by-products of water chlorination]
- Trilinolein
- [structure]
- Trinucleotide repeats
- [DNA]
- Trisomy
- [21]
- Tristearin
- [structure]
- Trophic level
- Position in a food chain such as a primary consumer or a secondary consumer.
- Trophoblast
- Tropism
- Automatic response of growth or orientation in a direction determined by the direction from which the stimulus strikes the organism.
- Trypsin
- Tryptophan
- [structure][repressor]
- TSH
- Thyroid-stimulating hormone
- Tubular secretion
- Tubulin
- [and microtubules]
- Tumor necrosis factor (TNF)
- Cytokine that triggers apoptosis. [More] [secretion by Th1 cells]
- Tumor Suppressor Genes
- Discussion
- Tundra
- Relatively flat, treeless plain north of the taiga and south of the polar regions.
- Turgor
- Distention of the wall of a plant cell by the accumulation of water within the cell. [in guard cells of leaf]
- Turner's syndrome
- Described
- Tyrosine
- [structure]