1. Metric System Primer Science uses the Metric system units as it’s standard for reporting data. Knowing the basics of the Metric system is essential. To report data on: Length – the standard is the Meter Mass – the standard is the Gram Volume – the standard is the Liter Temperature – Degrees Celcius Time - Second

2. Metric System Primer Length – Meter abbreviation “m” 1 meter, 1 m – a length approximately 39 inches (uses – 100 meter range in Olympic archery) The meter is subdivided into smaller units using standard prefixes of a set value: –Kilo = 1000 - Km = 1000 meters (used to measure long distances, for example: Distance from home to RVS campus 8.3 Km) Convert 8.3 Km to m. 8.3 X 1000 = 8300 meters *** simple, just move the decimal place to the right 3 spaces, that is the same as multiplying by 1000 (Very easy – even for us Math impaired biologists)

3. Metric System Primer (uses – 100 meter range in Olympic archery) too far for me

4. Metric System Primer Meter Ruler Divided into smaller more useful units Centimeter – “cm” 1/100 th of meter Millimeter – “mm” 1/1000 th of meter

5. Metric System Primer Meter Ruler Divided into even more smaller more useful units –Micrometer = micron, the µ symbol, Greek letter, 1/1000,000 meter (length of a cell) –Nanometer = nm, 1/1000, 000,000 (length of a molecule

6. Metric System Primer Average arrow: 29 inches, or.74 m (740mm)

7. Metric System Primer Relative size of things in Biology

8. Metric System Primer You must be able to quickly convert from one metric length to another. It is easy; you only have to move the decimal place the appropriate number of places. Example: A cell is 0.005 mm long. What is its length in microns? Remember that a micron is 1/000,000 th of a meter and that a mm is 1/1000 th of a meter. Which way do we move the decimal? How many places? Move to the right, 3 places (same as multiplying by 1000) answer is 5.0 microns. So, 5.0 microns is equivalent to 0.005 mm

9. Metric System Primer The metric unit for Mass is the Gram; symbol “g”. This a small mass unit. A BB from your childhood Daisy Red Rider weighs about a gram. Useful prefixes help. –Kilo; 1000, so a Kg is 1000 grams, a tea cup poodle might weigh only 2Kg ( close to 5 lbs) –My poodle weighs almost 6KG –Milli; 1/1000 th, so a mg is 1/1000 g, a medicine dosage might be 400 mg for IBU –Micro, 1/1000,000 th, so 100 µg is ____ mg – move decimal to the ____ by ____ places – (some bio toxins, Cbot, concentrations are measured in µg)

10. The “Princess”

11. Metric System Primer The metric system unit for volume is the Liter (not litter – that is for kittens) A liter is a large volume (about a quart) Useful prefixes help. –Milli – 1/1000, so 1ml is equal to.001L –Convert 350 ml to Liters. Ans: ____ L –Move decimal to the ____by ____ places –Micro – 1/1000,000, µ, so 400 µl of alcohol is equivalent to ________ ml. –Move decimal to the ____by ____ places –(** don’t forget that 1.0 ml of water is 1.0 cc of water and actually has a mass of 1.0 g)

12. Litter vs. liter

13. Metric System Primer Temperature: In the metric system, temperature is given in degrees Celsius,

14. Metric System Primer Temperature: In the metric system, temperature is given in degrees Celsius Useful temperatures to memorize Human body = 37 C (98.6 F) Water freezes at 0 C (32 F) Water boils at 100 C (212 F) Convert Temp from C to F = 1.8 C +32 Convert Temp from F to C = F-32 X5/9

15. Ice – zero degrees C body temp – 37 degrees C boiling water - 100 degrees C

16. Metric System Primer Metric standard unit for time is Second (s) Ks = _______ seconds ms = ________ seconds µs = ___________seconds ns = ______________ seconds I’ll give you some quiz questions on the metric system for practice in class.

17. Review questions on line http://www.austincc.edu/biology Go to the anatomy and physiology prep. Link Online Self-Prep Course for the Anatomy Assessment Test Online Self-Prep Course for the Anatomy Assessment Test Go to Metric system Module and review