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

Qualitative - Characteristics that can be described without measurements.
Quantitative - Characteristics that must be described with measurements, including numbers and standard units.
Quantum - The smallest amount of something that it is possible to have.
Quantum chemistry - Describes the way atoms combine to form molecules and the way molecules interact with one another, using the rules of quantum physics.
Quantum mechanics - The term 'quantum mechanics' is essentially synonymous with 'quantum physics'.
Quantum numbers - The four numbers used to describe the electrons in an atom.
Quantum physics - Describes the behavior of the world on very small scales, the scale of molecules, atoms, and below.
Quarks - Subatomic particles making up protons, neutrons, and other particles.

Raceme - An elongated inflorencence with simple pedicels along the central axis.
Radiant Energy - the energy of electromagnetic waves.
Radiation - The movement of heat through empty space in the form of infrared rays.
Radicle - The part of a plant embryo that will form the root of the new plant.
Radula - A flexible tongue-like strip covered with chitinous teeth in snails.
Rain shadow - The lack of precipitation on the lee side of a mountain range.
Raptors - Birds that have hooked beaks for tearing flesh.
Rare-Earth Metals - The two rows below the main body of the Periodic Table.
Rate - A special kind of ratio, indicating a relationship between two measurements - i.e., the rate of speed is the distance divided by the time.
Rate expression - A mathematical equation used to calculate the rate of a chemical reaction.
Rate of solution - Refers to how quickly a solute dissolves in a solvent.
Reaction center - One in about 250 chlorophyll molecules that actually processes light energy.
Reaction mechanism - The series of steps that must occur for a reaction to go to completion.
Reaction rate - The rate at which products form or reactants are used up.
Reactors - Large devices used to control nuclear chain-reactions.
Real image - One that can be projected onto a screen.
Realized intrinsic growth rate - The difference between natality and mortality in a population.
Receptacle - The swollen tip of a plant stalk supporting a flower.
Receptors - Nerve cells that receive information from internal and external stimuli.
Receptor sites - Specific places one a host cell where viruses attach.
Recombinant DNA - A combination of DNA from two or more sources.
Rectifier - A device that changes AC electricity to DC electricity.
Reducing agent - The reactant that gives up electrons during a chemical reaction.
Reduction - The gaining of electrons by an atom or ion.
Redox reaction - A reaction in which atoms or ions undergo changes in electron structure.
Reference point - A point assumed to be unmoving by which motion is described.
Reflection - The bouncing back of a wave after it strikes a boundary.
Refraction - The bending of a wave due to a change in speed.
Refractory period - The period of time it takes a neuron to return to its resting potential after being stimulated.
Regular flower - A flower with petals and sepals that are similar in size and shape.
Replication - The process of duplicating a DNA molecule.
Research paper - A comprehensive written communication about a specific topic.
Resistance force - The force applied by a machine.
Resistor - A device that allows a limited amount of current to pass through it.
Resolution - The ability of an optical device to show details clearly.
Resonance - The ablility of an object to vibrate by absorbing energy of its own natural frequency.
Resonance structure - An average representation of a molecule in which there are several possible ways for its atoms to be linked.
Respiration - The breaking down of pyruvic acid using molecular oxygen within cells to release energy; the exchange of carbon dioxide for oxygen in the lungs.
Restriction enzymes - Bacterial enzymes used to cut DNA molecules at specific sites.
Reticulate - Another term for net-veined leaves.
Retina - The lining of the back of the eye containing nerves that transfer images to the brain.
Reverberation - A combination of many reflected waves.
Reversible reaction - A chemical reaction that can reach equilibrium with the reaction continuing at the same rate in both directions.
Ribosomal RNA - rRNA, a globular form of RNA that is the major constituent of the ribosomes.
Ribosome - The site of protein synthesis in a cell.
Rhizome - Horizontal, underground stems that produce new shoots at their tips.
RNA - Ribonucleic acid, a single uncoiled strand that transmits information from DNA to the ribosomes during protein synthesis.
Rods - Nerve cells in the eye that are sensitive to light and dark.
Rolling Friction - Rolling friction is the frictional force associated with the rotational movement of a disc or other circular objects along a surface
Root cap - A shield of parenchyma cells covering and protecting the apical meristem at the root tip.
Root hairs - Small extensions of a root, greatly increasing the surface area of the root for absorption.
r-Selected species - A species capable of very rapid population growth, approximating an exponential growth pattern, followed by a crash in the adult population.
Rubric - A tool used for evaluation.
R-value - A measure of the efficiency of insulation.

Saliva - A mixture of water, mucus, and the digestive enzyme called salivary amylase.
Salt - A crystalline compound composed of the positive half of a base and the negative half of an acid.
Salt bridge - A solution connecting the two half-cells of a voltaic cell, allowing ions to move between the half-cells.
Samara - A dry fruit with 1-seed and winglike outgrowths.
Sand - Soil made of the largest particles, from 2mm down to 0.05mm (50 micrometers) in diameter.
Saprophytes - Bacteria that feed on dead or decaying organic matter.
Sapwood - The light-colored wood of a tree, consisting of active xylem cells.
Sarcoma - Cancer of the bone or muscle cells.
Saturated solution - A solution containing all the solute it is possible to dissolve under a given set of conditions.
Schr–dinger's Cat - The shorthand name for a hypothetical experiment dreamed up by Erwin Schr–dinger in 1935 to demonstrate the absurdity of the Copenhagen interpretation of quantum mechanics.
Science - A never ending search for truth.
Scientific calculator - Calculators that have trig and log functions and work in scientific notation.
Scientific law - A description of a natural phenomena that does not vary.
Scientific method - A process of logically finding solutions to problems.
Scientific name - A three part formal name for an organism accepted by scientists around the world.
Scientific notation - A way to write very large or very small numbers.
Scientific theory - A generally accepted explanation of a concept or a broad explaination of a natural phenomena.
Sclerenchyma - Short-lived plant cells with thick cell walls.
Scolex - The head of a tapeworm.
Screw - An inclined plane wrapped around a cylinder.
Scutes - Tough, transparent plates protecting the bones of the shell of turtle-like animals; the belly scales of snakes.
Secondary consumers - Animals that eat primary consumers.
Secondary growth - The growth in diameter of a plant stem produced by the lateral meristem.
Seed - A matured ovule.
Self-pollination - The transfer of pollen between flowers on the same plant.
Semipermeable - A membrane that allow some things to easily pass through and blocks other things.
Sepal - The outer floral structures protecting a flower.
Septum - A wall dividing a chamber, found in reptiles and fungi.
Sessile - Attached to some object; non-moving.
Setae - Hair-like bristles of some annelids used for locomotion.
Sex-influenced - Traits with genes located on autosomes, but express themselves differently in the sexes because of sex hormones.
Sex-linked - Traits with genes located on a sex chromosome.
Sexual reproduction - Producing offspring by the joining of gametes.
Schr–dinger - The person who developed an equation using quantum numbers to described an atomic model with electrons in three dimensions.
Series circuit - An electric circuit with only one path for the electrons to take.
Short-day plants - Plants that flower only when exposed to day lengths shorter than their critical length.
Shrub - A woody plant with several stems growing from the ground.
SI - An abbreviation for the International System of Measurement, used for all scientific data.
Sieverts - Units indicating the dose of radiation absorbed by living tissue.
Significant digit - A number indicating an actual measurement.
Silt - Soil made up of particles ranging in size from 50 micrometers down to 2 micrometers in diameter.
Silique - A dry fruit with 2 carpels and lose outer walls.
Simple fruit - A fruit derived from a single pistil of one flower.
Simple leaf - A leaf with a single blade on a single petiole.
Simple machine - Machines that do work with one movement.
Single displacement reaction - A single element replaces an element in a compound.
Slide rule - A mechanical device used to perform calculations.
Sliding Friction - when two solid surfaces slide against each other.
Slope - Used to describe the measurement of the steepness of a straight line. The slope is defined as the ratio of the "rise" divided by the "run" between two points on a line.
Snow - Formed by a gas changing directly into a solid
Soft water - Water with a low mineral content.
Soil - A mixture of organic parts and materials formed by the weathering of loose rock and mineral fragments at the surface of the Earth.
Solar system - All the planets and other objects orbiting the Sun.
Solar tracking - The phototropism of leaves or flowers as they follow the sun's daily movement.
Solid - A substance whose particles have a low kinetic energy, allowing the intermolecular forces of attraction to hold them tightly packed.
Solubility - A measure of how much of a solute can be dissolved in a given amount of solvent under certain conditions.
Solubility Rules - Rules used to predict the solubility of salts in water.
Solute - The least abundant substance in a solution.
Solvent - The most abundant substance in a solution.
Somatic - Refers to a regular body cell.
Somatic mutation - A mutation in body cells.
Somatic nervous system - Nerves that control voluntary movement of the skeletal muscles.
Sound - Longitudinal waves in matter composed of a series of compressions and rarefactions.
Space lattice - The three-dimensional arrangement of unit cells repeated over and over giving a crystal its overall geometric shape.
Spadix - A spike with a thickened, fleshy axis.
Spawning - The process by which fish eggs are externally fertilized.
Speciation - The formation of a new species from an existing one.
Species - A group of organisms that mate and produce fertile offspring.
Specific gravity - A ratio of the mass of a substance to the mass of an equal volume of water.
Specific heat - The number of calories needed to raise the temperature of one gram of a substance one Celsius degree.
Spectator ion - An ion that appears on both sides of a chemical equation.
Speed - The distance traveled by a moving object per unit of time.
Spike - An elongated inflorencence with flowers along the central axis that are sessil
Spinal nerves - Connect internal organs and muscles to the spinal cord.
Spirilli - A term used to indicate spiral-shaped bacterial cells.
Spirochetes - Gram-negative, spiral-shaped, heterotrophic bacteria that move with a corkscrew-like rotation.
Sputnik - The first artificial earth satellite.
Stable compound - A compound that does not spontaneously decompose in air.
Stamen - The male organ of a flower.
Standard pressure - One atmosphere, 760 mm Hg, or 101 kPa measured at sea-level.
Standard reduction potential table - A table showing the voltage of reduction half-reactions.
Standard solution - Any solution for which the concentration is precisely known.
Standard temperature - Zero degrees Celcius or 273 Kelvins.
Staphylo - A prefix used with the shape name to indicate a cluster of bacterial cells.
Standardized - to bring to or make use of an established standard: to standardize units of measure.
Static electricity - Electricity with high voltage and low power output.
Static Friction - Static friction occurs when the two objects are not moving relative to each other (like a rock on a table).
Steel - A metallic alloy using iron as the base element.
STD - Sexually transmitted disease.
Stenoecious species - A species with a low tolerance for many environmental factors and therefore a narrow distribution.
Steroid - An atypical lipid formed of four fused carbon rings and various functional groups.
Stigma - The open top of a flower pistil.
Stimulants - Drugs that increase nerve action, heart rate, and blood pressure.
Stipules - A pair of appendages located at the base of the petiole of some leaves.
Stoichiometry - A quantitative study of chemical changes.
Stolons - Stems trailing above ground, which often root at their nodes and tend to produce new plants if the stem is broken.
Stomata - Openings in leaves that regulate gases passing into and out of the plant.
STP - Standard temperature and pressure, ^o0 Celcius and 1 atmosphere.
Stratus - Layers of clouds shaped by cold horizontal winds.
Strepto - A prefix used with the shape name to indicate a filament of bacterial cells.
String Theory - A class of theories in physics that describes the fundamental particles and their interactions in terms of tiny one-dimensional entities - strings.
Stroma - The complex mixture of enzymes and water found in chloroplasts.
Strong force - Opposes the electromagnetic repulsion between protons in the nucleus; the strongest of the known natural forces.
Structural formula - A way to show all the atoms and bonds in an organic molecule.
Style - The hollow tube leading from the flower stigma to the ovary.
Subatomic particle - Any of the particles composing atoms.
Sublevel - An area within an electron energy level.
Sublimation - A solid changing into a gas without going through the liquid phase.
Sublittoral zone - The relatively shallow, highly productive floor of the continental shelf.
Subscripts - Small numbers to the lower right of chemical symbols, representing the number of atoms of that element in a compound.
Substrate - A molecule upon which an enzyme acts to yield a product.
Succession - The gradual replacement of populations in an area.
Succulent - Plants with thick, fleshy tissues in the leaves or stems for storing water.
Suction - A result of unequal pressure.
Suffrutescent - Semi-shrubby stems that turn woody in the lowest parts and remain alive over the winter when the higher parts die back.
Supersaturated solution - An unstable solution that has been forced to dissolve more solute than should be possible under a given set of conditions.
Superscript - A character set, printed, or written above and immediately to one side of another: In x² the superscript is 2. Supination - Rotating the palm of the hand upward.
Surface tension - The apparent elasticity of the surface of a liquid.
Suspension - A heterogeneous mixture in which the solute particles are large enough to be seen.
Symbiosis - The close association between two dissimilar organisms.
Symmetry - The way body parts are arranged around a point or central axis.
Synapse - A gap between each nerve cell.
Syngenesious - A flower whose stamens are attached by their filaments forming a ring.
Synthesis reaction - Two or more substances combine to form one complex substance.
Syntype - One of two or more specimens used by the author of a taxon if no holotype was designated, or one of two or more specimens designated as Types simultaneously in the original publication.
Syrinx - The "song box" of birds.