Metric System Primer

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Metric System Primer

• Science uses the Metric system units as its
  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

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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)

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Metric System Primer

• (uses 100 meter range in Olympic archery)
  too far for me

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Metric System Primer

• Meter Ruler
• Divided into smaller more useful units
• Centimeter cm 1/100th of meter
• Millimeter mm 1/1000th of meter

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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

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Metric System Primer

• Average arrow 29 inches, or .74 m (740mm)

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Metric System Primer

• Relative size of things in Biology

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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
  1/000,000th of a meter and that a mm is 1/1000th
  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

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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 1/1000th, so a mg is 1/1000 g, a medicine
  dosage might be 400 mg for IBU
• Micro, 1/1000,000th, so 100 µg is ____ mg
• move decimal to the ____ by ____ places
• (some bio toxins, Cbot, concentrations are
  measured in µg)

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The Princess
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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
• ( dont forget that 1.0 ml of water is 1.0 cc
  of water and actually has a mass of 1.0 g)

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Litter vs. liter
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Metric System Primer

• Temperature In the metric system, temperature
  is given in degrees Celsius,

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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

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Ice zero degrees C body temp 37
degrees C boiling water - 100 degrees C
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Metric System Primer

• Metric standard unit for time is Second (s)
• Ks _______ seconds
• ms ________ seconds
• µs ___________seconds
• ns ______________ seconds
• Ill give you some quiz questions on the metric
  system for practice in class.

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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  
• Go to Metric system Module and review