This preview shows pages 1–4. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Biology 1105 Exam #1 Exercise 2: Measurements in Biology Metric system used by scientists throughout the world to make measurements Also used everywhere in everyday life except in the US where most of the measurements are the antiquated English system of pounds, inches, feet, etc Based on units of 10, unlike the English system Conversions 1 inch = 2.5 centimeters 1 foot = 30 centimeters 1 yard = 0.9 meter 1 mile = 1.6 kilometers 1 ounce = 28 grams 1 pound = 0.45 kilograms 1 fluid ounce = 30 milliliters 1 pint = 0.47 liter 1 quart = 0.95 liter 1 gallon = 3.8 liters Metric Units: meter (m) basic unit of length liter (L) the basic unit of volume kilogram (kg) the basic unit of mass degree Celsius ( C) the basic unit of temperature Units of are indicated by Latin/Greek prefixes before the base units: Prefix (Latin) Division of Metric Unit Deci (d) 0.1 10 ^1 Centi (c) 0.01 10^2 Milli (m) 0.001 10^3 Micro (u) 0.000001 10^6 Nano (n) 0.000000001 10^9 Pico (p) 0.000000000001 10^12 Prefix (Greek) Multiple of Metric Unit Deka (da) 10 10^1 Hecto (h) 100 10^2 Kilo (k) 1000 10^3 Mega (M) 1000000 10^6 Giga (G) 1000000000 10^9 K  H  D  *(m,l,g)  D  C  M Meter (m) basic unit of length Units of area are squared units of length: o 1m = 100 cm = 1000 mm = 0.001 km = 1 X 103 km o I cm 2 = 100 mm 2 Most biologists measure lengths with metric rulers or metersticks Volume the space occupied by an object Units of volume are cubed (3D) units of length The liter (L) is the basic unit of volume o 1 L = 1000 cm 3 = 1000 mL a PIPET is used to extract and dispense volumes of liquid used to measure small volumes (25 mL or less) liquid is drawn into a pipet using a bulb o pipet pump GRADUATED CYLINDERS are used to measure larger volumes meniscus the interface i.e. between water and air; curved because of surface tension and the adhesion of water to the sides of the cylinder o when measuring liquid, position our eyes level w/ meniscus and read volume at lowest level Kilogram (kg) the basic unit of mass a kg = the mass of one thousand cubic centimeters (cm 3 ) of water at 4 C Biologists often measure mass with a TRIPLE BEAM BALANCE 3 beams o closest beam has 0.1g graduations o middle beam has 100g graduations o farthest beam has 10g graduations the mass of the object is the sum of the masses indicated by the weights on the 3 beams Density mass per unit volume density of water = mass/volume = about 1 Temperature measure of how kinetic energy of molecules; the amount of heat in a system measured with a thermometer calibrated in degrees Celsius Celsius scale is based on water freezing at 0 C and boiling at 100 C Can interconvert o C and degrees Fahrenheit ( o F) using the formula o 5( o F) = 9( o C) + 160 Numerical Data: Statistics  offer a way to organize, summarize, and describe data the data are usually samples of information from a much larger population of...
View
Full
Document
This note was uploaded on 04/14/2008 for the course SOC 1301 taught by Professor Park during the Spring '08 term at Baylor.
 Spring '08
 Park
 Sociology

Click to edit the document details