Essential Math of Biology

SI Prefixes Also, 1 mL = 1 cm3 and 1 L = 1 dm3 kilo- (k) 1000 deci- (d) 1/10 centi- (c) 1/100 milli- (m) 1/1000 micro- (µ) 1/1,000,000 nano- (n) 1/1,000,000,000 Also, 1 mL = 1 cm3 and 1 L = 1 dm3

The SI unit for length is the meter.

The SI unit for volume is the cubic meter (m3), but in biology we use liters, milliliters, or even microliters.

The SI unit for mass is the kilogram The SI unit for mass is the kilogram. In Biology you will almost always measure mass in grams.

Scientific Notation -- used to express very large or very small numbers, and/or to indicate precision (i.e., to maintain the correct number of significant figures) Form: (# from 1.0 to 9.999) x 10exponent 800 = 8 x 10 x 10 = 8 x 102 2531 = 2.531 x 10 x 10 x 10 = 2.531 x 103 0.0014 = 1.4 10 10 10 = 1.4 x 10–3

Change to scientific notation. 12,340 = 1.234 x 104 Put in standard form. 1.87 x 10–5 = 0.0000187 3.7 x 108 = 370,000,000 7.88 x 101 = 78.8 2.164 x 10–2 = 0.02164 Change to scientific notation. 12,340 = 1.234 x 104 0.369 = 3.69 x 10–1 0.008 = 8 x 10–3 1,000,000,000 = 1 x 109 6.02 x 1023 = 602,000,000,000,000,000,000,000

Using the Exponent Key EXP EE

The EE or EXP or E key means “times 10 to the…” How to type out 6.02 x 1023: How to type out 6.02 x 1023: 6 EE . 3 2 6 EE . 3 2 not… WRONG! 6 y x . 3 2 WRONG! or… x 1 6 . 2 EE 3 and not… TOO MUCH WORK. y x 3 2 x 1 6 .

Bored? Knowing how to use your calculator correctly might save you someday… Enter -22 into your calculator and figure out what went wrong.