First Children Encyclopedia

Reference section

Insulator Something that does

not let heat or electricity travel

through it very easily.

Invertebrate An animal

without a backbone.

Irrigation Bringing water to

land so plants can grow.

Mammal A warm-blooded

animal that has fur and feeds its

young with its own milk.

Mantle A layer of hot, solid rock

that lies beneath the Earth’s crust

and surrounds the Earth’s core.

Marsupial A mammal group in

which the female has a pouch for

its young.

Melanin A substance that our

body produces to protect our skin

from the sun.

Microchip A tiny electronic

device used in computers and

machines.

Mineral A solid with a

crystal structure that is found

in the ground

Monsoon A heavy rain-

and-wind storm that occurs

in southern Asia.

Morse code A system for

sending messages using dashes

and dots.

Mucus A sticky substance inside

your airways that traps germs.

Mummy A dead body that

has been preserved by removing

some of the organs, treating the

body with special chemicals, then

wrapping it in long strips of cloth.

Nucleus Structure inside a cell

that contains chromosomes and

is essential for making proteins.

Nutrient A substance taken

in by a plant or animal that is

essential for its growth.

Nymphs Insects that have not

yet become adults.

Omnivore An animal that eats

both plants and meat.

Orbit The path that one

object makes around another in

space, while under the influence

of gravity.

Ore A mineral that contains

a metal.

Ornithischian Bird-hipped

dinosaur.

Outback The remote, inland

areas of Australia.

Pasteurization A process

that uses heat to destroy bacteria

in food.

Percussion A type of musical

instrument that is hit or shaken

to produce a sound.

Pharaoh A powerful ruler of

ancient Egypt.

Photosynthesis The process

by which plants use sunlight to

make food from water and carbon

dioxide in the air.

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