IGCSE Glossary

Glossaries - GCSE chemistry

The number of protons in the nucleus of an atom. Also known as the atomic number

Glossaries - GCSE chemistry

A protist  is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus

Glossaries - GCSE chemistry

Glossaries - GCSE chemistry

These are polymers made of smaller carbohydrate molecules. An example is starch, which is made of lots of glucose molecules joined together in a chain.

Glossaries - GCSE chemistry

A chain of amino acids linked by peptide bonds. Proteins are made of one or more folded polypeptide chains.

Glossaries - GCSE chemistry

A transparent, crude oil-derived flammable hydrocarbon liquid that is used primarily as a fuel in most spark-ignited internal combustion engines. Density approximately  0.726 kg/l

Glossaries - GCSE chemistry

The period number in the periodic table shows how many shells are occupied by electrons.

Glossaries - GCSE chemistry

The nucleolus (, plural: nucleoli ) is the largest structure in the nucleus of eukaryotic cells. It is best known as the site of ribosome biogenesis. Nucleoli also participate in the formation of signal recognition particles and play a role in the cell's response to stress.

Glossaries - GCSE chemistry

Nanoparticles are particles between 1 and 100 nanometres (nm) in size 

Glossaries - GCSE chemistry

Methane is a chemical compound with the chemical formula CH₄ (one atom of carbon and four atoms of hydrogen). It is the simplest alkane, and the main constituent of natural gas.

Glossaries - GCSE chemistry

More than 70% of the elements of the periodic table are metals.  All metals conduct an electric current and react by losing electrons. Metals  therefore form positively charged ions when they react.

The structure of metals is often described as a lattice of positively charged ions in a "sea" of delocalised electrons. 

Glossaries - GCSE chemistry

Messenger DNA (mRNA)

A single stranded molecule made of a chain of ribonucleotides. Ribonucleotides are made of a sugar (ribose), a phosphate group and one of four different bases (A,G,C or U). mRNA is a complementary copy of a small piece of DNA called a gene. It is used in protein synthesis.

Glossaries - GCSE chemistry

Membranes are found surrounding the cell as well as around membrane bound organelles inside the cell. They are made of two layers of phospholipids and in those are embedded proteins and cholesterol.

Glossaries - GCSE chemistry

Marie Salomea Skłodowska Curie ( KEWR-ee; French: [kyʁi]; Polish: [kʲiˈri]), born Maria Salomea Skłodowska (Polish: [ˈmarja salɔˈmɛa skwɔˈdɔfska]; 7 November 1867 – 4 July 1934), was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity. As the first of the Curie family legacy of five Nobel Prizes, she was the first woman to win a Nobel Prize, the first person and the only woman to win the Nobel Prize twice, and the only person to win the Nobel Prize in two scientific fields. She was the first woman to become a professor at the University of Paris in 1906.

Glossaries - GCSE chemistry