There are seven different Standardised International (SI) units of measurements from which all others are derived. These are:

Name	Phenomenon	Units
meter	Length	m
second	time	s
kilogram	mass	kg
ampere	electric current	A
kelvin	thermodynamic temperature	K
mole	Amount of substance	mol
Luminous intensity	candela	cd

There are 22 derived physical phenomena, shown below. The names, phenomena, units and base units have been mixed up.

Sort them into the correct order and work out how their units may be represented with base SI units.
For each pheonomena, how many examples of biological application can you find? Can you find an example from biology for each one of these processes?

Name	Phenomenon	Units	Base units
becquerel, Bq	capacitance	A / V	m $^{2}$ m $^{- 2}$ cd
degrees Celsius, o C	electric conductance	C / V	K
coulomb, C	electric potential	cd sr	kg s $^{- 2}$ A $^{- 1}$
farad, F	electric resistance	J / kg	m kg s $^{- 2}$
gray, Gy	electrical charge	J / kg	m $^{1}$ m $^{- 1}$
henry, H	energy	J / S	m $^{- 1}$ kg s $^{- 2}$
Hertz, Hz	flux of light	lm / m $^{2}$	m $^{2}$ m $^{- 4}$ cd
joule, J	force	N / m $^{2}$	m $^{2}$ kg s $^{- 2}$
katal, kat	frequency	N m	m $^{2}$ kg s $^{- 2}$ A $^{- 1}$
lumen, lm	illuminance	V / A	m $^{2}$ kg s $^{- 2}$ A $^{- 2}$
lux, lx	inductance	V s	m $^{2}$ kg s $^{- 3}$
newton, N	magnetic flux	W / A	m $^{2}$ kg s $^{- 3}$ A $^{- 1}$
ohm, ?	magnetic flux density	Wb / A	m $^{2}$ kg s $^{- 3}$ A $^{- 2}$
pascal, Pa	plane angle	Wb / m $^{2}$	m $^{- 2}$ kg $^{- 1}$ s $^{3}$ A $^{2}$
radian, rad	power		m $^{- 2}$ kg $^{- 1}$ s $^{4}$ A $^{2}$
siemens, S	pressure		m $^{2}$ s $^{- 2}$
sievert, Sv	radiation dose		m $^{2}$ m $^{- 2}$
steradian, sr	solid angle		sA
tesla, T	temperature		s $^{- 1}$
volt, V	unit of catalytic activity		s $^{- 1}$ mol
watt, W
weber, Wb

(date sourced from the Bureau International des Poids et Mesures http://www.bipm.org/)

Other problems

Try Universal Time, Mass, Length to investigate the units implicit in the fundamental constants of nature.

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