OCR GCSE Combined Science A key terms

The direct modification of an organism’s genetic material to introduce a desired characteristic.

DNA that carries inherited information and instructions for making proteins.

Analysis of a person's DNA to identify particular genetic variants, such as alleles associated with disease.

A version of a DNA sequence that differs from another version. Different versions of a gene are called alleles.

Differences in genetic information between individuals of the same species.

The complete set of genetic material in an organism.

The combination of alleles an organism has for a gene, such as $Tt$.

A genetic intervention affecting eggs, sperm or the cells that produce them, so the change may be inherited by future generations.

An extensive network of atoms joined by strong covalent bonds, rather than a collection of separate molecules.

A regular, repeating three-dimensional arrangement of many positive and negative ions.

The variety of species across the whole planet.

A reduction in sunlight reaching the Earth's surface, to which atmospheric particulates can contribute.

A splint whose flame has been blown out but whose tip remains hot and glowing.

A hormone released by the pancreas that raises blood glucose concentration by causing liver glycogen to be converted into glucose and the glucose to be released into the blood.

A simple sugar made during photosynthesis; it is a carbohydrate.

A small molecule that joins to fatty acids to form lipids; one glycerol molecule forms the backbone of a triglyceride.

A polymer made from glucose that stores carbohydrate in liver and muscle cells.

The change in the vertical-axis quantity divided by the corresponding change in the horizontal-axis quantity.

A single layer of carbon atoms covalently bonded in a continuous hexagonal network.

The force by which objects with mass pull towards one another.

A region of space in which an object with mass experiences a gravitational force.

Gravitational force per kilogram of mass, measured in newtons per kilogram (N/kg). It is represented by $g$.

The attractive force between objects with mass.

Energy stored because of an object's height in a gravitational field. Raising the object increases its gravitational potential energy.

The energy store associated with the position of objects in a gravitational field; it increases when an object is raised.

The warming of Earth’s surface because gases in the atmosphere absorb outgoing infrared radiation and emit infrared radiation, some of it back towards the surface.

A gas, such as carbon dioxide or methane, that absorbs infrared radiation emitted by the Earth and contributes to atmospheric warming.

Water held underground in rocks.