Lion Science Scientia non habet inimicum nisp ignorantem		Northwest High School Jefferson County, MO

T

Taproot - A primary root that grows much larger than the other roots of a plant.
Tau - A type of "heavy" electron.
Taxidermy - Preserving a vertebrate in a life-like form.
Taxonomy - The branch of biology that names and groups organisms according to their characteristics and evolutionary history.
Technology - Putting scientific knowledge to practical use; applied science.
Telophase - The stage of mitosis when the chromosomes disappear and the nuclear membrane reforms.
Temperate - Not immediately disease causing.
Temperature - A measure of the average kinetic energy of molecules. DT means a change in temperature.
Temporal lobe - Part of the brain involved in hearing and memory.
Temporary magnets - Materials that are easy to magnetize, and loose their magnetism quickly.
Tendon - Tough, inflexible bands of connective tissue attaching muscle to bone.
Teratogen - Anything that can cause malformations of an embryo or fetus.
Terminal velocity - The point at which air resistance offsets the weight of a falling object, stopping its acceleration.
Ternary acid - An acid composed of hydrogen, oxygen, and another element.
Terrapins - Semi-aquatic animals, equally at home in water or on land.
Tetrad - The set of four haploid cells formed from one cell during meiosis.
Tetrapod - An animal with four appendages.
Tertiary consumers - Animals that eat secondary consumers.
Thecodont - Having teeth rooted in the jaw bone.
Theory of Everything (TOE) - Any theory which attempts to combine gravity and some form of grand unified theory in one package.
Thermal Energy - The energy portion of a system that increases with its temperature.
Thermal expansion - The expansion of a substance due to an increase in the motion of its molecules because of heat.
Thermal Pollution - A temperature change in natural water bodies caused by human influence.
Thermoacidophiles - Bacteria that live in extremely acidic environments (pH less than 2) that have extremely high temperatures (up to 110 ^oC).
Thermodynamics - The study of the flow of energy in matter.
Thermometer - An instrument for measuring temperature.
Thermostat - A device that uses heat changes to turn a current on and off automatically.
Thigmotropism - A plant growth response to contact with a solid object.
Thorn - A sharp and stunted stem branch, sometimes modified leaves or leaf parts.
Thought experiment - An experiment which is not intended to be carried out as a practical reality, but is "all in the mind".
Thrombase - A chemical in snake venom that causes local thrombosis, the coagulation of blood in the blood vessels at the site of the bite.
Thromboplastin - Released by platelets to react with calcium and prothrombin in the blood plasma to produce thrombin in the first stages of clotting.
Throughfare channels - Vessels that allow blood to bypass a capillary bed.
Thylakoid - Each of the flattened sacs which make up the granum of chloroplasts.
Thymine - One of two single carbon ring nitrogen bases in DNA.
Timbre - The quality of sound produced by the blending of pitches.
Tincture - A solution with alcohol as a solvent.
Tissue - A group of cells that perform a common function.
Titration - An analytical procedure in which a standard solution is used to determine the concentration of another solution.
Tolerance - The body becoming less and less responsive to a physically addictive drug.
Topographic map - A map that models the Earth's surface geology.
Torr - A unit of pressure used to indicate mm Hg.
Tortoises - Terrestrial, poor swimming animals with a shell and stumpy legs.
Toxins - Substances that disrupt the metabolism of organisms.
Trachea - A non-muscular tube leading from the pharynx to the lungs, sometimes called the windpipe.
Transcription - The process of forming mRNA from DNA.
Transfer RNA - tRNA, a single folded RNA strand that bonds with a specific amino acid.
Transformer - A device used to increase or decrease the voltage of alternating current.
Transistor - A sandwich of three semiconductor crystals used to amplify an electric current.
Transition Metals - Elements in Groups 3-12 on the periodic table.
Translation - Assembling of protein molecules from information encoded in mRNA.
Translocation - The movement of water and photosynthetic products through the vascular tissues of a plant.
Translucent - Light passes through a material but is scattered so you cannot see clearly.
Transmutation - A change in the number of protons in a nucleus producing an atom with a different atomic number.
Transparent - Light passes through a material so you can see clearly.
Transpiration - The evaporative loss of water from leaf stomata.
Transverse wave - The medium particles move at right angles to the direction of wave travel.
Tree ring - Formed by the contrast in size of cambium cells grown under differing moisture conditions.
Trichinella - A roundworm that causes trichinosis from eating undercooked pork.
Triglyceride - Three molecules of fatty acid combined with one molecule of glycerol.
Triple-beam balance - A device with three movable tares to measure the mass of matter.
Triple point - The temperature and pressure at which all three phases of a substance can exist in equilibrium.
Trochophore - The pear-shaped larva of Mollusks.
Tropism - A plant movement toward or away from an environmental stimulus.
True fruit - A fruit composed of only the plant ovary wall.
Tuber - Thick, fleshy underground stems that serve as organs for food storage and reproduction.
Tumor - A mass of cells resulting from uncontrolled, abnormal cell division.
Turtle - Marine animals with a shell and paddle-like appendages.
Tympanic membrane - A circular "eardrum" behind each eye of amphibians and reptiles.
Type specimen - The original specimen designated by the author in a scientific collection; the Holotype.

Umbel - An inflorescence having several branches arising from a common point at the end of the peduncle.
Unbalanced Force - Two forces acting upon an object in which one force is greater than the other. Unbalanced forces cause acceleration.
Unit cell - The simplest repeating unit in a crystal.
Universe - The volume of space including all the planets, stars, and material between them.
Unsaturated solution - A solution containing less solute than is possible to dissolve under a given set of conditions.
Uracil - One of two single carbon ring nitrogen bases in RNA.
Uranium - A radioactive chemical element in the periodic table that has the symbol U and atomic number 92. Uranium has the highest atomic weight of the naturally occurring elements (see plutonium).
Urea - The most common mammalian metabolic waste, CH₄N₂O.

Vacuole - Storage sites within a cell.
Valence - The number of electrons gained or lost by an atom to comply with the octet rule; oxidation number.
Valence electrons - Electrons in the outer energy level of an atom.
Van de Graaff Generator - A device used to produce large quantities of static electricity.
Van der Waals forces - Intermolecular attraction between the electrons of one atom and the protons of another.
Vapor - The gaseous phase of a substance that is not a gas at room temperature.
Vaporization - The changing of a liquid to a gas.
Variety - A classification division of a species, used most often in plants.
Vascular tissue - The conducting tissues of vascular plants.
Vector - A quantity that has both magnitude and direction.
Veins - Thin-walled blood vessels that carry blood under low pressure toward the heart.
Velocity - Speed in a given direction.
Venation - The arrangement of the principal veins in a leaf blade.
Ventral - Refers to the bottom surface of an organism.
Ventricle - The pumping chamber of the heart.
Viability - The ability of a seed to germinate in the future.
Virtual image - One that appears behind the surface of the mirror.
Virulent - Disease causing.
Visceral - Derived from or associated with the gut or coelom.
Viscosity - The resistance of a fluid to flow.
Vitamins - Complex organic molecules that assist many chemical reactions within the body.
Viviparous - The developing young is nourished inside the body of the female.
Voltaic cell - A device that changes chemical energy into electrical energy.
Volatile - A liquid that readily evaporates at room temperature.
Voltage - The electric potential difference between two points.
Voltmeter - An instrument to measure the potential difference between two half-cells in a voltaic cell.
Volume - The amount of space an object takes up.
Vomerine teeth - Two rough pads in the roof of the mouth of some amphibians.

Warning coloration - The bold, bright color patterns that make dangerous or poisonous animals clearly recognizable and warn predators away.
Water cycle - Water moving from the atmosphere to the Earth's surface and back.
Watts - Units of power, Joules per second.
Wave - A disturbance that transfers energy through matter or space.
Wavelength - The distance between two consecutive crests of a wave.
Wax - A long fatty acid chain combined with a long alcohol chain.
Weather - Short-term changes in the state of the atmosphere.
Weak force - The force responsible for radioactive decay.
Weathering - The chemical decomposition or physical disintegration of rocks and minerals.
Wedge - A moving inclined plane.
Weight - A measure of the pull of gravity on an object.
Wheel and axle - A lever that rotates in a circle around a fulcrum.
White matter - Nerve cell fibers in the brain.
Wilting - The loss of water pressure in the tissues of a plant.
Withdrawal - The physical or mental reaction to lack of a drug.
Wood - Plant stem xylem cells with thick cell walls.
Work - A force acting through a distance.

X-Axis - On a graph, the x-axis is the horizontal axis or the bottom of the graph. Place the independent variable on the x-axis.
Xylem - Straw-like tubes conducting water and minerals upward in a plant.

Y-Axis - On a graph, the y-axis is the vertical axis or the side of the graph. Place the dependent variable on the y-axis.

Zooplankton - Made up of protists, it is a primary source of energy in aquatic ecosystems.
Zygote - Formed when sperm and egg cells join in sexual reproduction.