1. Standards of Measurement
Biology
Fall 2016

2. International System of Units (SI)
SI Unit is a system of measurements used worldwide.
Several SI base units are used:
Kelvin
Meter
Mole
Gram
Candela
Second
Ampere

3. International System of Units (SI)
Length- The distance between two points.
Volume- The amount of space occupied by and object.
Mass- The amount of matter in an object.
Density- The amount of mass per unit volume of a material.
Time- The interval between two occurring events.

4. International System of Units (SI)
Meter
Quantity Measured: Length
Symbol: m
A meter is about
3.28 feet
Five steps in a staircase
The width of a doorway
The height of a 5 year old
Half the length of a bed
The depth of the shallow end of a swimming pool
Four rungs up a ladder

5. International System of Units (SI)
Gram
Quantity Measured: Mass
Symbol: g
A gram is about
One paperclip
One pen cap
A piece of gum
The weight of any US bill
A GRAM DOES NOT MEASURE WEIGHT!

6. International System of Units (SI)
Second
Quantity Measured: Time
Symbol: s
An hour is 60 minutes, and a minute is 60 seconds, so an hour is: 60 × 60 = 3,600 seconds
A day is 24 hours so: 1 day = 24 × 60 × 60 = 86,400 second

7. International System of Units (SI)
Ampere
Quantity Measured: Electric Current
Symbol: A
A quantity of charge is measured in units called COULOMBS, and the word Ampere means the same thing as "one Coulomb of charge flowing per second." If we were talking about water, then Coulombs would be like gallons, and amperage would be like gallons-per- second. 

8. International System of Units (SI)
Scientists have produced superheated gas exceeding temperatures of 2 billiondegrees    Kelvin, or 3.6 billion degrees Fahrenheit.
Scientists have produced superheated gas exceeding temperatures of 2 billiondegrees    Kelvin, or 3.6 billion degrees Fahrenheit.
International System of Units (SI)
Kelvin
Quantity Measured: Temperature
Symbol: K
Facts about Kelvin:
Water freezes at K (That’s 0°C, 32°F)
Water boils at K (That’s 100°C, 212°F)
Absolute Zero is 0 K (Cant get any colder than 0 K)
Scientists have produced a superheated gas exceeding temperatures of 2 billion degrees K, or 3.6 billion degrees F!

9. International System of Units (SI)
Mole
Quantity Measured: Amount of a substance
Symbol: mol
When chemists want to have a chemical reaction come out they need to know how many molecules of each kind of chemical they have, so they measure the chemicals in moles. A mole is the atomic weight of a molecule of the chemical in grams.
So a mole of a molecule like hydrogen (H) with an atomic weight of 1 is one gram. A complex molecule like glucose (C6H12O6) has an atomic weight of 180, so one mole is 180 grams.
Let’s do the math!
Carbon: 12(6)=72 Hydrogen: 1(12)=12 Oxygen: 16(6)= =180

10. International System of Units (SI)
Candela
Quantity Measured: Intensity of Light
Symbol: cd
Superheroes Unite!

11. Common SI Prefixes Prefix: Kilo Prefix: Deci Prefix: Centi Example:
Symbol: k
Multiplying factor: 1,000
Prefix: Deci
Symbol: d
Multiplying factor: 0.1
Prefix: Centi
Symbol: c
Multiplying factor: 0.01
Example:
Kilometer
Kilogram
Decisecond
Decimeter
Centimeter
centigram

12. Common SI Prefixes Prefix: Milli Prefix: Micro Prefix: Nano Example:
Symbol: m
Multiplying factor: 0.001
Prefix: Micro
Symbol: µ
Multiplying factor:
Prefix: Nano
Symbol: n
Multiplying factor:
Example:
Millisecond
Milligram
Microgram
Micrometer
Nanometer
nanosecond

13. International System of Units (SI)
Final Thoughts