Centimeters & inches
Temperature Conversion
A simple online conversion tool for length, weight, and volume
http://www.worldwidemetric.com/metcal.htm
http://www.onlineconversion.com/
A conversion table between US units and metric system.
http://www.merriam-webster.com/mw/table/metricsy.htm
Commonly used metric system units, symbols, and prefixes
http://lamar.colostate.edu/~hillger/common.html
International System of units (SI) at the NIST.
http://www.physics.nist.gov/cuu/Units/
Various llinks and recommendations on Biochemical & Organic Nomenclature, Symbols & Terminology etc. in all area of biochemistry and molecular biology.
http://www.chem.qmul.ac.uk/iubmb/
UIPAC recommendations on Organic & Biochemical Nomenclature, Symbols & Terminology
http://www.chem.qmul.ac.uk/iupac/