PAAET Nursing and Health Sciences Aptitude Test key terms

The net movement of particles from an area where they are more concentrated to an area where they are less concentrated, caused by their random motion, until they are spread evenly.

The movement of water molecules through a partially permeable membrane from a dilute solution towards a more concentrated one, which tends to even out the concentration on both sides.

A protein that speeds up one specific chemical reaction in a living cell by lowering the energy barrier for that reaction, and is not used up in the process.

One of the alternative versions of a gene that an organism may inherit, for example the version that produces brown eyes rather than blue eyes.

The particular combination of alleles an organism carries for a gene or group of genes, which is inherited and often written with letters such as AA, Aa or aa.

The observable characteristics of an organism, such as eye colour, height or blood group, produced by its genotype interacting with the environment.

A microorganism, such as a bacterium, virus or fungus, that causes disease when it enters the body or infects its tissues.

A protein produced by certain white blood cells that recognises and binds to a specific foreign substance, helping the body to destroy or neutralise it.

The amount of a substance that contains about 6.02 x 10^23 particles, a convenient counting unit chemists use to relate numbers of particles to masses.

A measure of solution concentration equal to the number of moles of dissolved substance in one litre of solution, written with the unit mol/L.

A scale from 0 to 14 showing how acidic or alkaline a solution is; values below 7 are acidic, 7 is neutral and values above 7 are alkaline.

A substance that gives hydrogen ions when dissolved in water, producing a solution with a pH below 7 that reacts with bases and with some metals.

A substance that accepts hydrogen ions or releases hydroxide ions in water, giving a pH above 7 and reacting with an acid to form a salt and water.

The reaction in which an acid and a base cancel each other's properties, forming a salt and water and moving the pH of the mixture towards 7.

A substance that makes a chemical reaction go faster by providing a pathway that needs less energy, while the substance itself is left unchanged.

A chemical bond in which two atoms share one or more pairs of electrons, as in the bonds holding the hydrogen and oxygen atoms of a water molecule together.

A way of comparing two quantities of the same kind by showing how many times one contains the other, often written in the form 3:5.

A statement that two ratios are equal, used to calculate an unknown quantity when two things change at the same relative rate.

A number expressed as a part of one hundred, so that 45% means 45 out of every 100 and quantities of different sizes can be compared easily.

The average of a set of values, found by adding all the values together and then dividing by how many values there are.

The middle value of a data set once the values are arranged in order; if there is an even number of values, it is the average of the two middle ones.

The value that appears most frequently in a data set; a set may have one mode, more than one, or no mode at all.

A number between 0 and 1 that expresses how likely an event is, calculated by dividing the number of favourable outcomes by the total number of equally likely outcomes.

The speed of an object together with the direction in which it is moving, measured in metres per second, so a change of direction is also a change of velocity.

The mass of a material per unit of volume, usually quoted in kilograms per cubic metre or grams per cubic centimetre, showing how closely matter is packed.

The force pressing on a surface divided by the area of that surface, measured in pascals, so the same force produces more pressure over a smaller area.

One of the standard units agreed internationally for measuring quantities, such as the metre for length, kilogram for mass and second for time, used so measurements can be compared.

The difference in electrical potential energy per unit charge between two points in a circuit, measured in volts, which drives charge around the circuit.

The rate at which electric charge flows past a point in a circuit, measured in amperes, and possible only when the circuit forms a complete loop.

The relationship stating that, for a conductor kept at a steady temperature, the voltage across it equals the current through it multiplied by its resistance.

The central point that a passage is trying to get across, which the rest of the text explains, supports or illustrates.

A conclusion a reader works out from clues in a text together with general knowledge, rather than one that the writer states directly.

A word that has the same meaning, or very nearly the same meaning, as another word, such as 'begin' and 'start'.

A word whose meaning is the opposite of another word's, such as 'hot' and 'cold'; recognising opposites helps in vocabulary questions.

A hint found in the words or sentences around an unfamiliar word that helps a reader work out what the word means.

The grammar rule that a verb must match its subject in number, so a singular subject takes a singular verb and a plural subject takes a plural verb.

A comparison in which two pairs of words or ideas are related in the same way, used in reasoning tests to check whether that relationship has been understood.

An ordered set of numbers, letters or shapes that follows a rule, so the next item can be predicted once the pattern has been identified.

A statistical link showing that two quantities tend to rise or fall together; it does not on its own prove that one of them causes the other.

The property of a shape that allows it to look unchanged after being folded, turned or reflected in a particular way, often tested in spatial reasoning questions.