News tagged with molecules

Related topics: cells , protein , atoms , cancer cells , cancer

Total recall: The science behind it

Is it possible to change the amount of information the brain can store? Maybe, according to a new international study led by the Research Institute of the McGill University Health Centre (RI-MUHC). Their ...

Nov 13, 2014
popularity 4.8 / 5 (21) | comments 1

Discovery opens up possibility of slowing cancer spread

A trawl through a library of more than 50,000 'small molecules' has identified a potential candidate to inhibit the spread of cancer cells throughout the body. Reported today in the journal Nature Communications, the mo ...

Nov 12, 2014
popularity 4.9 / 5 (9) | comments 0

Molecule fights cancer on two fronts

Researchers at the University of Leeds have made a new synthetic anti-cancer molecule that targets two key mechanisms in the spread of malignant tumours through the body.

Nov 13, 2014
popularity 4.8 / 5 (5) | comments 0

Single enzyme is necessary for development of diabetes

An enzyme called 12-LO promotes the obesity-induced oxidative stress in the pancreatic cells that leads to pre-diabetes, and diabetes. 12-LO's enzymatic action is the last step in the production of certain small molecules ...

Aug 14, 2014
popularity 4.4 / 5 (5) | comments 0

Molecule

A molecule is defined as a sufficiently stable, electrically neutral group of at least two atoms in a definite arrangement held together by very strong (covalent) chemical bonds. Molecules are distinguished from polyatomic ions in this strict sense. In organic chemistry and biochemistry, the term molecule is used less strictly and also is applied to charged organic molecules and biomolecules.

In the kinetic theory of gases the term molecule is often used for any gaseous particle regardless of its composition. According to this definition noble gas atoms are considered molecules despite the fact that they are composed of a single non-bonded atom.

A molecule may consist of atoms of a single chemical element, as with oxygen (O2), or of different elements, as with water (H2O). Atoms and complexes connected by non-covalent bonds such as hydrogen bonds or ionic bonds are generally not considered single molecules.

No typical molecule can be defined for ionic crystals (salts) and covalent crystals (network solids), although these are often composed of repeating unit cells that extend either in a plane (such as in graphene) or three-dimensionally (such as in diamond or sodium chloride). The theme of repeated unit-cellular-structure also holds for most condensed phases with metallic bonding. In glasses (solids that exist in a vitreous disordered state), atoms may also be held together by chemical bonds without any definable molecule, but also without any of the regularity of repeating units that characterises crystals.

This text uses material from Wikipedia licensed under CC BY-SA