Lebanese Baccalaureate - General Sciences (GS) key terms

The instantaneous rate at which a function changes with respect to its variable, defined as the limit of the difference quotient as the interval shrinks to zero.

The value a function's output approaches as its input approaches a given point, whether or not the function is actually defined at that point.

A property of a function at a point where the limit exists, the function is defined there, and the two are equal; informally, the graph has no break or jump.

A quantity accumulating infinitely many infinitesimal contributions, interpreted geometrically as the signed area between a curve and an axis, computed as the reverse of differentiation.

Any function whose derivative equals a given function; primitives of the same function differ only by an additive constant.

The straight line touching a curve at one point whose slope equals the derivative of the curve at that point.

A line that a curve approaches ever more closely as it extends, without necessarily ever meeting it; found by studying limits at infinity or near excluded values.

A number written a + bi, where a and b are real and i satisfies i squared equals minus one; it has a real part, an imaginary part, a modulus, and an argument.

A list of numbers in which each term after the first is obtained by adding a fixed constant to the previous term.

A list of numbers in which each term after the first is obtained by multiplying the previous term by a fixed nonzero ratio.

A number between zero and one expressing how likely an event is, equal to the ratio of favourable equally likely outcomes to all outcomes in the sample space.

The probability that one event occurs given that another event is known to have occurred, defined as the joint probability divided by the probability of the known event.

Two events whose joint probability equals the product of their separate probabilities, meaning the occurrence of one does not change the chance of the other.

The set of all possible outcomes of a random experiment, from which events are selected as subsets.

A numerical value assigned to each outcome of a random experiment, described by its probability distribution, expectation, and variance.

The vector sum of forces acting on a body equals the product of its mass and acceleration, so acceleration is proportional to net force and inversely proportional to mass.

A reference frame in which a body with no net force acting on it remains at rest or moves in a straight line at constant speed.

The vector quantity equal to mass times velocity of a body; in an isolated system its total value is conserved during interactions.

The energy a body possesses because of its motion, equal to one half of its mass times the square of its speed.

The energy transferred by a force acting along a displacement, equal to the scalar product of the force vector and the displacement vector.

The sum of a body's kinetic energy and its potential energy; it stays constant when only conservative forces do work.

A vector field at each point of space equal to the force per unit positive charge that a test charge would experience there.

The scalar quantity equal to electric potential energy per unit charge at a point; the potential difference between two points drives current in a conductor.

The electrostatic force between two point charges is proportional to the product of the charges and inversely proportional to the square of the distance between them.

A measure of the magnetic field passing through a surface, equal to the field strength times the area times the cosine of the angle between field and surface normal.

The production of an electromotive force in a conductor when the magnetic flux through it changes with time, as stated in Faraday's law.

The spontaneous transformation of unstable nuclei into other nuclei, accompanied by emitted particles or radiation, following an exponential decrease in the number of parent nuclei.

The time required for half of the radioactive nuclei present in a sample to decay; it is characteristic of each radionuclide and independent of sample size.

The amount of substance containing as many elementary entities as there are atoms in twelve grams of carbon-12, namely Avogadro's number of entities.

The number of elementary entities in one mole of a substance, approximately 6.02 times ten to the power twenty-three per mole.

The mass of one mole of a substance in grams per mole, numerically equal to the sum of the atomic masses of the atoms in its formula.

A logarithmic scale of acidity equal to the negative base-ten logarithm of the hydrogen ion concentration in moles per litre; values below seven are acidic.

A species that releases hydrogen ions to a base; in water it increases the hydrogen ion concentration and reacts with bases to form salts.

A solution that resists large changes in pH when small amounts of acid or base are added, usually because it contains a weak acid with its conjugate base.

The stage of a titration at which the amount of titrant added has exactly reacted with the amount of substance being analysed, according to the reaction stoichiometry.

A reaction in which a species loses electrons and its oxidation number increases; it is always accompanied by a simultaneous reduction.

A reaction in which a species gains electrons and its oxidation number decreases; it always occurs together with an oxidation.

A chemical reaction involving transfer of electrons from a reducing agent, which is oxidised, to an oxidising agent, which is reduced.

An organic compound formed when a carboxylic acid reacts with an alcohol with elimination of water, recognisable by its characteristic sweet smell.

A protein that speeds up a specific biochemical reaction by lowering its activation energy, acting on a particular substrate at its active site.

The region of an enzyme where the substrate binds and the chemical reaction is catalysed, whose shape determines the enzyme's specificity.

The molecule on which an enzyme acts, binding at the active site and being converted into products during the catalysed reaction.

Adenosine triphosphate, the universal energy carrier of cells; breaking its terminal phosphate bond releases energy for cellular work.

The set of metabolic reactions in which cells break down organic molecules, using oxygen, to release energy stored as ATP and produce carbon dioxide and water.

The first stage of cellular respiration, occurring in the cytoplasm, in which one glucose molecule is split into two pyruvate molecules with a net gain of ATP.

The process by which green plants use light energy to convert carbon dioxide and water into organic matter, releasing oxygen as a by-product.

The green pigment in chloroplasts that absorbs light energy for photosynthesis, chiefly in the red and blue regions of the spectrum.

A type of cell division producing two daughter cells with the same chromosome number as the parent cell, used for growth and repair.

A reduction division producing four daughter cells each with half the chromosome number of the parent, generating genetic variation in gametes.

A structure of DNA and associated proteins carrying the genes of a cell; human body cells contain forty-six, arranged in twenty-three pairs.

One of the alternative forms of a gene occupying the same position on homologous chromosomes, which may be dominant or recessive.

The genetic makeup of an organism with respect to one or more genes, describing which alleles it carries.

The observable characteristics of an organism resulting from the interaction between its genotype and the environment.

A protein produced by immune cells that binds specifically to a foreign antigen, marking it for neutralisation or destruction.

A systematic approach to investigating nature in which a hypothesis is proposed, tested by controlled experiments, and accepted, revised, or rejected according to the evidence.

A testable, falsifiable proposed explanation for an observation, stated clearly enough that experiments could show it to be wrong.

The group in an experiment that does not receive the treatment being tested, providing a baseline against which the effect on the experimental group is compared.

The digits in a measured value that carry meaning about its precision, used to report results and round calculations consistently.

The range within which the true value of a measured quantity is expected to lie, reflecting the limits of the instrument and the procedure.

A simplified representation of a real system, used to explain observations and make predictions, whose validity is judged by how well it fits evidence.