AIIMS B.Sc. Nursing key terms

The acceleration of an object depends directly on the net force acting on it and inversely on its mass. It is written as force equals mass times acceleration, F = ma.

For a conductor kept at constant temperature, the current flowing through it is directly proportional to the voltage across it. Resistance equals voltage divided by current, V = IR.

A number showing how much a transparent medium slows light compared with a vacuum. It equals the speed of light in vacuum divided by the speed in the medium.

The heat energy absorbed or released when a substance changes state, such as melting or boiling, without changing temperature. It is usually measured per unit mass.

A repeating back-and-forth motion in which the restoring force points toward a fixed centre and grows in proportion to displacement from that centre. Pendulums and springs show it.

Pressure applied to a confined fluid transmits equally in all directions and to every part of the container. Hydraulic brakes and lifts use this principle to multiply force.

The heat energy needed to raise the temperature of one kilogram of a substance by one degree Celsius. Water has a high value, so it heats and cools slowly.

When light travels from a denser medium to a less dense one beyond a critical angle, it reflects back inside instead of refracting out. Optical fibres use this effect.

The amount of a substance containing exactly 6.022 × 10^23 representative particles, such as atoms, molecules or ions. It links mass in grams to numbers of particles.

The number of particles in one mole of any substance, approximately 6.022 × 10^23 per mole. It allows chemists to convert between particle counts and amounts in moles.

A scale from 0 to 14 measuring how acidic or basic a water solution is. Values below 7 are acidic, 7 is neutral, and above 7 is basic.

Atoms of the same element with the same number of protons but different numbers of neutrons. They have identical chemical properties but different masses and sometimes differ in stability.

A chemical bond formed when two atoms share one or more pairs of electrons. It usually occurs between non-metal atoms and creates molecules rather than charged ions.

A reaction in which a substance loses electrons or gains oxygen, or in which its oxidation number increases. It is always accompanied by reduction of another substance.

A solution that resists large changes in pH when small amounts of acid or base are added. It usually contains a weak acid and its conjugate base, or a similar pair.

The concentration of a solution expressed as the number of moles of solute dissolved per litre of solution. It changes slightly with temperature because volume changes.

A type of cell division producing two genetically identical daughter cells with the same chromosome number as the parent. It is used for growth, repair and asexual reproduction.

The movement of water molecules through a semi-permeable membrane from a region of lower solute concentration to one of higher solute concentration. It continues until concentrations balance.

The ability of a living organism to keep its internal conditions, such as temperature, pH and glucose level, within narrow limits despite external changes. It involves feedback mechanisms.

A biological catalyst, usually a protein, that speeds up a chemical reaction by lowering its activation energy. Each enzyme acts on specific substrates and is not consumed.

A nerve cell that receives, processes and transmits electrical impulses. It has dendrites for input, a cell body, and an axon that carries signals toward other cells.

The microscopic functional unit of the kidney that filters blood and produces urine. It includes a glomerulus, renal tubule and collecting duct, and performs reabsorption.

A molecule, often foreign, that the immune system recognises as a threat and can trigger a specific antibody or T-cell response. Examples include proteins on pathogens.

The process by which green plants, algae and some bacteria use light energy to convert carbon dioxide and water into glucose, releasing oxygen. Chlorophyll captures the light.

Basic human rights guaranteed to Indian citizens by Part III of the Constitution, such as equality, freedom of speech, and protection of life. Courts can enforce them.

A way of expressing a number as a fraction of 100, written with the percent sign. It is used to compare proportions, calculate discounts, interest and changes.

A comparison of two or more quantities by division, showing how many times one value contains or is contained in another. Ratios are often written with a colon.

A single value representing the centre of a set of numbers, calculated by adding all values and dividing by how many are present. It is also called the arithmetic mean.

A word having the same or nearly the same meaning as another word. For example, 'big' and 'large' are synonyms, though they may differ in tone or usage.

A word opposite in meaning to another word. For example, 'hot' and 'cold' are antonyms, and prefixes such as un- often create them.

A fixed expression whose meaning cannot be understood from the literal meanings of its individual words, such as 'break the ice' meaning start a conversation.

A grammatical construction in which the subject of a sentence performs the action of the verb. In 'The nurse gave the medicine', the nurse acts.