Glossary

Explore the glossary for definitions of scientific terms used in this course.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

Ampere

A unit of electric current equal to a flow of one coulomb per second.

ADP

Adenosine diphosphate (ADP) is a molecule used in metabolism and is to transports chemical energy within cells (see also ATP). During metabolism ADP is converted to ATP, which stores energy, and this process replenishes a human body’s energy supplies.

ATP

Adenosine triphosphate (ATP) is a molecule used in metabolism to transports chemical energy within cells (see also ADP). ATP stores the energy produced during respiration process, and is transformed in ADP to release energy that a human body can use when needed. This process is akin to recharging a rechargeable battery. Only oxygen can enable the human body to generate and store energy in this way.

B

C

Covalent bond

A covalent bond is a bond formed between two atoms by sharing a pair of electrons.

D

E

Electric charge

A covalent bond is a bond formed between two atoms by sharing a pair of electrons.

Electromagnetic field

A physical field produced by charged objects. Electric charges can be positive or negative.

Electromagnetic radiation

A kind of radiation including visible light, radio waves, gamma rays, and X-rays.

Electrostatic forces

Electrostatic forces are the attractive or repulsive forces between different particles and materials based on their electrical charges.

ElectronVolts (eV)

A unit of energy, commonly used in high-energy astrophysics, equal to approximately 1.6 x 10⁻¹⁹ joules.

F

G

H

I

Igneous rock

Rock that is formed by the cooling of magma or lava.

Ion

An ion is a charged atom or molecule. Ions can be positively or negatively charged.

Ionising radiation

A form of radiation that carries enough energy to free electrons from atoms or molecules, thereby creating ions.

Ion exchange

Ion exchange resin is made up of small porous beads that trap some ions whilst releasing other ions. Ions are charged atoms.

J

Joule

The joule is the SI unit of energy. Scientists use SI units to ensure comparability.

K

Kilopascal

A kilopascal is 1000 pascals. See pascal entry.

L

Lux

The SI unit of illuminance and luminous emittance. You can think of it as light density.

M

Mole

The mole is the SI unit for the amount of a substance. It is expressed as the mass of a substance that contains the same number of atoms or molecules as 12 g or carbon. This number of atoms is given by the Avagadro constant, 6.022140857 × 10²³ atoms or molecules per mole.

N

Nutrients

Food substances that may be used for cell building, cellular repair or making important molecules needed for our bodies.

O

Oxidiser

A substance that transfers an oxygen atoms to another substance, or that removes an electron from another species.

P

Partial pressure

The hypothetical pressure of that gas if it alone occupied the volume of a mixture of gases at the same temperature.

Pascal

The pascal is the unit used to measure pressure in the Systeme International (SI). Scientists use SI units to ensure comparability. A pascal is defined as a Newton per square metre.

Permafrost

Rock or soil that has been continually frozen for two years.

Photosynthesis

The process through which plants use sunlight to convert carbon dioxide and water into glucose (for energy) and oxygen.

Proton-proton reaction

A proton-proton reaction is a reaction in stars that converts hydrogen to helium.

R

Regolith

A layer of loose, uncompacted dirt, dust and broken rocks that sits on top of solid rock.

S

Silicate rocks

Silicate rocks make up around 90% of the Earth’s crust and are contain silicon and oxygen and various other elements.

T

U

V

W

X

Y

Z