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DEFINITIONS
1.Disease
Infectious Disease: A disease that can be transmitted from person to person or from organism to
organism, and is caused by viruses, bacteria or fungi.
Non-Infectious Disease: Diseases that are not caused by a pathogen and cannot be spread from
one person to another. They can be caused by factors such as the environment, nutritional
deficiencies or genetic inheritances.
Antibody- protein molecule produced by B cells as a primary immune defense, each molecule has a
site that can bind with a foreign antigen (such as on a virus or bacterium). The antibody disables the
antigen and signals other immune defenses.
Antigen- any substance that can stimulate the production of antibodies and combine specifically with
them.
Vaccine- any preparation used as a preventive inoculation to lead to immunity against a specific
disease, usually using a killed or weakened part of the bacteria or viruses, to stimulate antibody
production.
Pathogen- any disease-producing agent such as a virus, bacterium, or other microorganism.
Virus- an infectious agent that replicates only within the cells of living hosts such as bacteria, plants,
and animals. They are made of an RNA or DNA core, a protein coat, and, in more complex types, a
surrounding envelope.
Bacteria- one-celled organisms, spherical, spiral, or rod-shaped and appearing singly or in chains
2.Reproduction
Fertilisation: creation by the physical union of male (sperm) and female (ova) gametes
Ovulation: the process of ovum being released from the ovary (usually midway in the menstrual
cycle)
Menstruation: the periodic discharging of blood and cells from the lining of the uterus
Menopause: The period that marks the permanent cessation of menstrual activity, usually occurring
between the ages of 40 and 58.
3. Genetics
Hybrid: The combination of two or more different things. An offspring resulting from the cross
between parents of different species or sub-species.
Cloning: The man-operated process of extracting DNA from a host cell and implanting it to function
in another type of cell.
Transgenic: This term describes an organism that has had genes from another organism put into its
genome through recombinant DNA techniques.
DNA (also known as Deoxyribonucleic acid): A double-stranded nucleic acid that contains the genetic
information for cell growth, division, and function. DNA must be copied correctly in an organism or
else it leads to a mutation which leads to disease or cancer.
Gene: A gene is the basic unit of heredity in a living organism. All living things depend on genes.
Dominant: an allele that produces the same phenotype whether its paired allele is identical or
different.
Recessive: producing its characteristic phenotype only when its allele is identical.
Genotype: the particular alleles at specified loci present in an organism.
a group of organisms sharing a specific genetic constitution. It is the genetic characteristics
Phenotype: what an organism looks like as a consequence of the interaction of its genotype and the
environment
Chromosome: A chromosome is an organized structure of DNA and protein that is found in cells.
Hereditary: the passing of traits to offspring (from its parent or ancestors). This is the process by
which an offspring cell or organism acquires or becomes predisposed to the characteristics of its
parent cell or organism.
Replication: is the process whereby DNA makes a copy of itself before cell division
Mutation: any event that changes genetic structure; any alteration in the inherited nucleic acid
sequence of the genotype of an organism
Mutagen: – a mutagen is a physical or chemical agent that changes the genetic material (usually
DNA) of an organism and thus increases the frequency of mutations above the natural background
level
Waves
Opaque – not transparent, cannot see through it
Amplitude - the maximum displacement of a periodic wave from its rest position
Blind spot - the point where the optic nerve enters the retina; not sensitive to light
Frequency - Frequency is the number of waves per second
Short sighted - a refractive defect of the eye which allows it to see up close but have poor
long distance vision
Period - the interval taken to complete one cycle of wave/oscillation
Transparent - able to be seen through with clarity
Trough - the lowest point of a wave
Series – similar things placed in order or happening one after another
Translucent – able to see through with some distortion
Velocity - speed: distance travelled per unit time
Long-sighted - Hyperopia, also known as farsightedness, longsightedness or hypermetropia, is
a defect of vision caused by an imperfection in the eye
Wave: A carrier of energy
Loudness: volume: the magnitude of sound
Energy: energy produced for domestic or industrial use
Pitch: The sound of a wave
Wavelength: the distance between two points in the same phase in consecutive cycles of a
wave
Refraction: the change in direction of a propagating wave (light or sound) when passing
from one medium to another.
Crest: The top of a wave
Chemistry
Group number: A group number element resides in the period table it tells you which group
the element belongs to, metallic, gas, or liquid
Neutron: neutrons are found in the atomic nuclei. They are subatomic particles which have
no net electric charge.
Molecule: A molecule is the smallest particle in a chemical element or compound they are
made up of atoms that are held together by chemical bonds.
Proton: a proton is a subatomic particle found in the nucleus of every atom. Protons are the
factor which contributes to an elements atomic number. It has a positive charge
Compound: a compound is a substance that comprises of two or more different chemical
elements.
Atom: the smallest component of an element having the chemical properties of the
element, consisting of a nucleus containing combinations of neutrons and protons
Periodic table: A tabular arrangement of the elements according to their atomic numbers so
that elements with similar properties are in the same column.
Element: one of a class of substances that cannot be separated into simpler substances by
chemical means.
Electron: The electron is a subatomic particle that carries a negative electric charge. It has
no known substructure and is believed to be a point particle.
Isotope: any of two or more forms of a chemical element, having the same number of
protons in the nucleus, or the same atomic number, but having different numbers of neutrons
in the nucleus, or different atomic weights.
Atomic mass- The mass of an atom of a chemical element expressed in atomic mass units.
Reactant- It is a chemical substance that is present at the start of a chemical reaction.
Product- A chemical substance formed as a result of a chemical reaction.
Valency- The number of electrons ( on the outer shell) in which an element must gain or lose
in order to attain a noble gas structure.
Formula- It is a representation of a substance using symbols for its constituent elements.
Element- It is a pure chemical substance consisting of one type of atom distinguished by its
atomic number.
Compound- A compound is composed of more than one part; to combine so as to form a
whole.
Combustion- It is the process in which a substance reacts with oxygen to give heat and light.
Corrosion - A product of corroding, as rust.
Precipitation - The precipitating of a substance from a solution.
Neutralization - A reaction between an acid and a base that yields a salt and water.
Decomposition- Separation into constituents by chemical reaction.
Indicator- A substance, as litmus, that indicates whether a substance is acidic, basic or
neutral
Flammability - easily set on fire; combustible; inflammable.
Acid - having only a part of the hydrogen of an acid replaced by a metal or its equivalent:
an acid phosphate. Has a pH ranging from 1-6
Base - A compound that reacts with an acid to form a salt, as ammonia, calcium hydroxide,
or certain nitrogen-containing organic compounds. Has a pH ranging from 8-12
pH – Indicates the acidity or alkalinity of a solution on a scale of 0 to 14, where less than 7
represents acidity, 7 neutrality, and more than 7 alkalinity.
Ion – an atom that loses or gains an electron
Electricity
Current - a flow of electrons (charged particles)
Transformer - an electrical device by which alternating current of one voltage is changed to
another voltage
Conductor- a device designed to transmit electricity, heat, etc.
Voltmeter: A voltmeter is an instrument used for measuring the electrical potential difference
between two points in an electric circuit.
Transverse waves: Pertaining to width or the widthwise dimension; perpendicular to the axis.
The wave moves up and down but the energy moves forward
Electromagnetic: Referring to the combined electric & magnetic fields caused by electron
motion through conductors.
Ammeter: a device used for measuring current flow at any point in an electrical circuit.
Resistor- an electrical device that resists the flow of electrical current
Voltage- the rate at which energy is drawn from a source that produces a flow of electricity
in a circuit; expressed in volts
Circuit- an electrical device that provides a path for electrical current to flow
Electrocution- is also frequently used incorrectly to refer to any electric shock received.
Parallel circuit- a closed circuit in which the current divides into two or more paths before
recombining to complete the circuit