science vocab

Created by kimaro17 

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absolute zero

the lowest possible temperature, about -273 degrees Celsius

acid

a substance that forms hydronium ions in water; having a pH less than 7

acid rain

rain made acid by absorbing sulfur and nitrogen oxides from polluted air

adrenalin

a hormone of the adrenal gland, secreted in times of emergency

air mass

a large body of air characterized by certain values of temperature and humidity

algae

simple, green organisms with cell walls, but without the complex structure of plants

alkali

a strongly basic hydroxide

alloy

a substance composed of two or more metals

alternating current

an electric current that reverses direction periodically

amino acid

organic chemicals with an acid group (-COOH) at one end and an amino group (-NH2) at the other; the constituent molecules of proteins

anemia

substandard concentration of red blood cells

antibody

a blood protein that protects the body from foreign chemicals or microorganisms

aorta

the largest artery, carrying blood out of the left ventricle

artery

a muscular-walled blood vessel that distributes blood to the body tissues

atmosphere

the layer of air surrounding the earth

atom

the smallest part of an element

bacteria

the smallest and simplest one-celled organisms, having neither nucleus nor other organelles

barometer

an instrument for measuring atmospheric pressure

bedrock

the solid rock underlying the loose material at the earth's surface

boiling point

the temperature at which, at any given pressure, the liquid and gas phases of a substance are in equilibrium

calorie

a quantity of heat energy, equal to 4.185 joules; the Large Calorie of the nutritionist is a kilocalorie, equal to 1000 calories

capillary

1) a thin tube into which water can rise by adhesion to the surface 2) a tiny blood vessel connecting an artery to a vein and providing interchange of materials between blood and tissue

catalyst

a substance that increases the rate of a chemical reaction without being used up in the reaction

chemical formula

conventional representation of the atomic composition of a compound

chemical reaction

a process in which the molecules or ionic composition of one or more substances is altered

colon

the large intestine

concentration

the amount of a substance contained in a given volume of a solution or other mixture

conductor

a material through which heat or electrical current may pass

digestion

the process of enzymatic breakdown of large organic molecules into smaller, soluble ones

dilute solution

a solution in which the solute has a low concentration

DNA

deoxyribose nucleic acid, the substance of the genes

ductless gland

an endocrine organ

ecology

the study of the relationships between organisms and with their inorganic environment

electric charge

the property of particles (such as electrons and protons) by which they exert forces on each other without respect to their mass

electric current

a flow of electric charge, typically carried by electrons through a metal or by ions through a solution or a plasma

electromagnetic waves

disturbances in electric and magnetic fields propagating through space

electron

a particle found in all atoms, having a small mass and a single unit of negative electric charge

electrostatic force

the force particles exert on each other because of their electric charge

element

a substance consisting of only one species of atom, so that it cannot be decomposed by chemical means

embryo

an organism in the earliest stages of its development

endocrine organ

a gland that secretes hormones into the blood

energy

a physical quantity having the dimension of work and measured in joules, whose total quantity remains constant through all interactions and transformations

enzyme

a substance, usually a protein, produced by living cells and acting as a catalyst

epicenter

the point on the earth's surface directly above the geological shift that causes an earthquake

erosion

the movement of rock, sand, etc., due to natural forces

esophagus

the tube that carries food from the mouth to the stomach; gullet

evaporation

conversion of a liquid into the gaseous phase by escape of molecules from the surface

evolution

the process by which species undergo drastic changes over long periods of time

excretion

the disposal of metabolic wastes from the body, as by urination

fault

a crack in the earth's crust, along which crustal movement takes place

fermentation

an enzyme-controlled reaction that takes place in the absence of oxygen, such as the conversion of sugar to alcohol by the action of yeast

fertilization

1) the process of applying nutrients to the soil to stimulate plant growth 2) the union of a sperm and an egg cell to form a zygote

fission

1) reproduction of a one-celled organism by splitting into two equal parts 2) the splitting of an atomic nucleus into approximately equal parts, with the release of energy

flood plain

the flat region around an old river, which becomes covered with water at times of high runoff

food chain

an array of organisms in which each serves as food for the one above

fossil

the preserved remains or casts of a long-extinct organism

frequency

the number of cycles completed in a unit time in any cyclic phenomenon, such as a vibration

front

the boundary between two air masses

fusion

1) the melting of a solid 2) a nuclear reaction in which two small nuclei combine to form a larger one, accompanied by the release of energy 3) the union of isogametes of one-celled organisms

galaxy

an agglomeration of many millions of stars

gamete

a sex cell, such as egg or sperm

gas

a substance, usually of very low density, that has no surfaces of its own but will spread to fill its container

gene

the particle that carries hereditary info from one generation to another and controls the production of proteins in a living cell

genetics

the study of biological inheritance

glacier

a large mass of ice moving down a valley or across a continent

glucose

the simple sugar that forms the fundamental energy supply of all nucleated organisms

gravity

the mass-dependent force by which any two objects in the universe attract each other

greenhouse effect

the warming of the earth resulting from atmospheric gases trapping heat that reradiates from the earth's surface

habitat

the part of an ecosystem that is occupied by a given organism

heat

energy that passes from one system to another because of a difference in temperature

helix

a spiral shaped like a spring, characteristics of the DNA molecule

herbivore

an animal that eats plants only (what Hibari hates the most)

hormone

a substance, secreted into the blood by an endocrine gland, that controls chemical processes in other parts of the body

humidity

the amount of water vapor in the air

igneous rock

rock formed by the hardening of liquid rock emerging from deep within the earth, either to the surface or within the crust

inertia

the property of objects to remain in a state of rest or uniform motion in a straight line unless acted on by an outside force

infrared rays

electromagnetic waves of wavelength longer than those of visible light, but shorter than microwaves

insulator

a substance that blocks the passage of heat or electric current

insulin

a hormone, produced in the pancreas, that controls the metabolism of glucose

ion

an atom or group of atoms that has acquired either a positive charge or a negative charge by gaining/losing electrons

isobar

a line on a weather map connecting points of equal barometric pressure

isotope

a variety of an element distinguished by its atomic mass number, but having the same atomic number as all other isotopes of the element

jet stream

a rapidly flowing mass of air high in the atmosphere

Kelvin scale

the SI temperature scale, which has its zero at the absolute zero of temperature

kinetic energy

the energy of an object as measured by its mass and velocity

latent heat

the heat added or removed from a substance that produces a change of phase with no change in temperature

latitude

the distance north or south of the equator measured in degrees

light year

the distance light travels in a year

liquid

a substance that takes the shape of its container, up to a definite upper surface

liter

a unit of volume equal to 1000 cubic cm

longitude

the distance east or west of the prime meridian, measured in degrees

lunar eclipse

condition in which the earth comes between the sun and the moon so that the moon is in the earth's shadow

magnet

a device made of a ferromagnetic material, such as steel, which can exert forces on other such materials

magnetism

the excess force exerted on each other by charges in motion

mass

the quantity of substance in an object measured either by its acceleration when a force is applied or by its gravitational attraction to other objects

melting

the change of matter from solid to liquid

melting point

the temperature at which the solid and liquid phases of a substance can exist in equilibrium

mineral

an earth substance with specified chemical constitution

molecule

a particle consisting of one or more atoms bound together, and comprising the smallest quantity of a non-ionic substance

muscle

an organ that controls body functions by carrying electrochemical impulses

natural selection

the tendency of individuals or species best adapted to a particular environment to leave larger numbers of offspring

nerve

an organ that controls body functions by carrying electrochemical impulses

neuron

a nerve cell

neutron

a neutral particle that is part of the nuclei of atoms, with mass slightly larger than that of a proton

nitrogen

a gaseous element that makes up 79 percent of the atmosphere

nucleus

1) the massive, charged center of an atom, composed of protons and neutrons 2) a structure in a cell, surrounded by a membrane and containing the chromosomes 3) a particle of dust in the atmosphere around which water condenses, forming a raindrop

organic compound

a molecular chemical compound based on carbon

osmosis

the diffusion of water through a membrane

outcrop

the part of the bedrock protruding through overlying sediments

ovary

in animals, an organ that produces egg cells; part of the stigma of a flower that contains the ovules

thermometer

a device for measuring temperature

toxin

a poisonous substance produced by bacteria

vaccine

a material used to induce immunity to a specific disease

vertebrae

the bones that are arrayed linearly to form the back-bone of vertebrates

virus

a submicroscopic particle that can become self-reproducing inside a living cell

volt

the unit of measure of electric potential difference, which provides the condition for the flow of an electric current

weight

the gravitational force that the earth or other astronomical object exerts on an object near its surface

X-ray

electromagnetic radiation of wavelength shorter than ultraviolet

zygote

a cell formed by the fusion of two gametes

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