Scientific Measure, Conversions

Basic Quantities

Length-meter (m)
Mass- gram (g)
Volume-Liter (L)
Time-second (s)
Temperature- degrees Kelvin (K)
Amount of Substance- Mole (mol)
Heat Energy- joule (J)
Electric Current- ampere (A)
Luminous intensity- candela (cd) Energy-joules (J) calories (c)

Prefixes
tera- T 10^12
giga- G 10^0
mega- M 10^6
kilo- k 10^3
hecto- h 10^2
deka- da 10^1
deci- d 10^-1
centi- c 10^-2
milli- m 10^-3
micro- μ 10^-6
nano- n 10^9
pico- p 10-12
femto- f 10^-15
atto- a 10^-18

Metric-English
1.00 in = 2.54 cm
1.00 kg= 2.20 lb
1.00 lb= 454 g
1.00 L= 1.06 qt

1cm^3; (1cc)= 1 mL
1 fluid ounce = 29.6 mL (cc)

K= C+ 273
C= 5/9 (F-32)
F= 9/5 C+ 32

Kelvin and Celsius have 100 degrees between freezing and boiling, where Fahrenheit has 180.
the freezing and boiling points in degrees for
Kelvin 273, 373
Celsius 0, 100
Fahrenheit 32, 212

Example Problems

1)an epithelial cell has a diameter of 63.5 microns (μ)

a) express the diameter in meters
63.5 μ or 63.5x10^-6 meter = 10^1
the epithelial cell is 6.35x10^-5 m

b) in Angstroms (Å)
63.5 μ or 63.5x10^-6 to Å 10^-10
=63500

Note: when going from a larger unit to a smaller unit, the number must increase, and when going from a smaller unit to a larger unit the number must decrease.

Connect to Biostudies
Viruses are very small, and so they are generally visualized with the use of electron microscopy. The most sensible unit for viral particles is nm. This is equal to 10^-9 meters or 100 micron (μ).

Bacterial cells are typically measured in microns(μ) and visualized using light microscopy with oil immersion, of 1000X or greater.

Animal and plant cells are typically measured in microns and observed using conventional light microscopy (~40-400X). Some cells are large enough (like eggs) to be seen with the naked eye.


Liquid volume example.
1) Adult male has total blood volume of 5.15 L
a) express this volume in mL
5.15L= 5150 mL
b) 5.15L= 51.5 dL