Glossary

abdomen
rear part of an insect's body
absorb
take something in
adductor
strong muscle of an oyster that attaches the oyster's body to its shell
amplifier
device that makes sounds louder
anemometer
instrument used to measure wind speed
antennae
delicate, long pair of movable parts on the top of an insect's head used for smelling and touching
atom
smallest part of a material that retains the properties of that material
attract
pull toward
ballast tanks
air and water tanks that make a submarine move up and down in the water
barometer
any instrument used to measure atmospheric pressure
biceps
large set of muscles in the upper arm
carbon dioxide
gas made up of carbon and oxygen
cartilage
soft, bonelike material between bones
center of gravity
point at which the whole of an object's weight is concentrated
chromatography
technique for separating chemical substances by taking advantage of the different rates at which the substances are absorbed from a moving liquid
chromosomes
tiny parts of a cell that carry genes
colors
sensations produced by visible light entering the human eye
compass
instrument used for determining directions
concave
having a hollowed surface; bending inward
concentrated
full strength; not mixed with anything
condensation
change of the state of a substance from a vapor to a liquid
cones
special parts of the eye that distinguish colors
converted
changed
convex
having a protruding surface; bending outward
deflate
collapse by letting out air
density
a measure of weight in relation to volume
dew
warm, moist air that comes into contact with cooler objects, causing moisture to appear on them
dew point
temperature on a thermometer when dew or vapor just begins to form
diameter
distance across the middle of a circle
dilute
make weaker
displaced
pushed out of the way
double convex lens
a lens that is thicker in the middle than at the edges
dye
coloring substance
elastic
material that returns to its original state after it has been distorted by a force
electromagnet
temporary magnet that allows the flow of electricity through a wire
energy
ability to do work
farsighted
able to see distant objects better than close-up objects
focal point
point at which lines of light come together
force
power or energy that creates something
friction
the force that resists motion between two objects rubbing against one another
fulcrum
point at which a lever rests when lifting an object
gears
wheels with teeth around the edges that come together and turn each other
gene
small unit of a cell that passes characteristics from one generation to another
genetics
the study of why living things look and behave as they do
gravity
force that attracts objects to the center of the Earth and keeps planets and other heavenly bodies in orbit
hemisphere
half section of the Earth
humidity
amount of water vapor in the air
ignite
set on fire
inflate
put air into an object so that it expands
iris
colored part of the eye around the pupil
kaleidoscope
small tube of mirrors in which patterns are produced
kinetic energy
energy due to motion
latex
elastic type of material
left valve
the part of an oyster that attaches to objects in the water
lens
curved transparent material that bends rays of light
lever
bar resting on a support that is pushed down at one end to lift the other end
light
form of energy that is the source of illumination
lightning
flash in the sky produced when electricity passes from one cloud to another
lines of force
lines in the field around a magnet that show which poles attract and which repel
liquid
matter in a state in which molecules are able to move around but are still held in contact with the molecules around them
machine
any device that modifies a force so work can be done more easily
magnet
a material that attracts certain other materials, such as metals
magnetic
having the properties of magnets
magnetic field
the attraction area around magnets
mantle
fold of tissue lining an oyster's shell
metabolism
process in living things that turns food into energy, new cells, and waste
mirror
a surface that reflects most of the light falling on it
molecule
smallest part of an element or compound capable of leading a separate existence
mollusk
animal that grows a shell to protect itself
nearsighted
able to see close-up objects better than distant objects
organism
living thing
ovipositor
long, pointed, divided segment of an insect's body at the end of the abdomen used for laying eggs in soft ground
particles
very tiny pieces
pendulum
weight hanging from a fixed point
periscope
instrument that makes it possible to see around corners
pigment
substance in things that gives color
pivot
point at which something turns
plastron
under-shell of a turtle
plumb line
device used to find vertical lines
poles
north and south ends of a magnet
polluted
unclean, impure, or dirty
potential energy
energy that is stored
pressure
force acting on each unit of area of a surface
primary colors
yellow, blue, and red
pulley
simple machine using rope and one or more wheels to change the direction of a force
pulse
regular beating in the arteries caused by movements of the heart as it pumps blood
pupil
opening in the center of the eye
rainbow
arc-shaped band of colors
reflect
bounce light off
refract
bend light
repel
push away
resistance
ability to withstand a force
secondary colors
combinations of two primary colors
secrete
give off or release
segment
section
shadow
the dark area where light rays would have fallen if not for an object in the way
solar energy
energy from the sun
spectrum
a series of colored bands of light that can be seen when light is broken up, such as by a prism
spinal column
long row of connected bones forming the backbone
spinal cord
nerve tissue running down the spinal column
static electricity
stationary electric charge
stethoscope
instrument for listening to sounds of the body
surface tension
force that attracts water molecules to one another and that holds the surface of water together
telescope
optical device containing lenses and mirrors for magnifying distant objects
thermometer
device for measuring temperature
thorax
middle part of an insect's body
triceps
small set of muscles in the upper arm
vapor
a substance in its gas state
vertebrates
animals with a backbone
vertical
straight up and down
viscosity
ability of fluids to flow
volume
amount of space inside something
weight
downward force exerted on an object by gravity
wind chill
cooling effects of the winds and temperatures on skin