OCR GCSE Combined Science B key terms

Modifying an organism's genome to introduce desirable characteristics.

The DNA that carries instructions controlling how a cell or organism develops and functions.

An increased likelihood of developing a condition because of inherited alleles; it does not make the condition inevitable.

Examining an individual's DNA to identify particular alleles or other genetic differences.

Differences in DNA between individuals of the same species.

The complete set of genetic material in an organism.

The combination of alleles an organism has, for example Tt for a particular gene.

An extended network containing very many atoms joined by strong covalent bonds, rather than separate small molecules.

A large, regular, three-dimensional arrangement of positive and negative ions held together by electrostatic attraction in all directions.

A large, repeating arrangement of particles extending throughout a substance.

A hormone released by the pancreas that raises blood glucose concentration by stimulating the breakdown of liver glycogen into glucose and its release into the blood.

A sugar made during photosynthesis that can be used in respiration or to make substances needed for growth and storage.

An insoluble polymer of glucose used to store glucose in liver and muscle cells.

The change in the vertical-axis quantity divided by the corresponding change in the horizontal-axis quantity: $m=\frac{\Delta y}{\Delta x}$.

A single layer of carbon atoms arranged in hexagonal rings, forming a giant covalent structure one atom thick.

The gravitational force per kilogram of mass at a location, measured in newtons per kilogram (N/kg).

Energy stored because of an object's position in a gravitational field, measured in joules (J).

The warming of Earth’s surface and lower atmosphere because greenhouse gases absorb outgoing infrared radiation and emit infrared radiation in all directions, including towards the surface.

An atmospheric gas that absorbs and emits infrared radiation, such as carbon dioxide or methane.

Water stored underground in spaces and cracks in rock.

A vertical column of the Periodic Table. Elements in the same main group have similar chemical properties because their atoms have similar outer-shell electron arrangements.

One of a pair of specialised cells that control the opening and closing of a stomatal pore.

The division of a continuous habitat into smaller, separated patches.

A protein in red blood cells that binds oxygen reversibly, allowing oxygen to be picked up in the lungs and released to tissues.

An equation showing the electron transfer in one oxidation or reduction reaction, with atoms and charge balanced.

The time taken for half the radioactive nuclei in a sample to decay, or for its activity to halve.

A negatively charged ion formed when a halogen atom gains one electron, for example chloride, $\mathrm{Cl^-}$.