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Biology for AP® Courses

C | Measurements and the Metric System

Biology for AP® CoursesC | Measurements and the Metric System

Measurements and the Metric System
Measurement Unit Abbreviation Metric Equivalent Approximate Standard Equivalent
Length nanometer nm 1 nm = 10−9 m
  • 1 mm = 0.039 inch
  • 1 cm = 0.394 inch
  • 1 m = 39.37 inches
  • 1 m = 3.28 feet
  • 1 m = 1.093 yards
  • 1 km = 0.621 miles
micrometer µm 1 µm = 10−6 m
millimeter mm 1 mm = 0.001 m
centimeter cm 1 cm = 0.01 m
meter m
  • 1 m = 100 cm
  • 1 m = 1000 mm
kilometer km 1 km = 1000 m
Mass microgram µg 1 µg = 10−6 g
  • 1 g = 0.035 ounce
  • 1 kg = 2.205 pounds
milligram mg 1 mg = 10−3 g
gram g 1 g = 1000 mg
kilogram kg 1 kg = 1000 g
Volume microliter µl 1 µl = 10−6 l
  • 1 ml = 0.034 fluid ounce
  • 1 l = 1.057 quarts
  • 1 kl = 264.172 gallons
milliliter ml 1 ml = 10−3 l
liter l 1 l = 1000 ml
kiloliter kl 1 kl = 1000 l
Area square centimeter cm2 1 cm2 = 100 mm2
  • 1 cm2 = 0.155 square inch
  • 1 m2 = 10.764 square feet
  • 1 m2 = 1.196 square yards
  • 1 ha = 2.471 acres
square meter m2 1 m2 = 10,000 cm2
hectare ha 1 ha = 10,000 m2
Temperature Celsius °C 1 °C = 5/9 × (°F − 32)
Table C1
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