Unit 4Unit 4Research TechniquesResearch Techniques

ALAT Chapter 15ALAT Chapter 15

Introduction to Science and Introduction to Science and MetricsMetrics

Scientific TerminologyScientific Terminology Most scientific terms Most scientific terms

have a prefix, root have a prefix, root and/or suffix, which and/or suffix, which makes them easier to makes them easier to understand – such as understand – such as hyperglycemia hyperglycemia

Hyper- (more than)Hyper- (more than) Glyc (glucose)Glyc (glucose) -emia (blood)-emia (blood)

ecto- (outside), ecto- (outside), endo- (inside), endo- (inside), -cide (killing), -cide (killing), -tomy, (to cut into), -tomy, (to cut into), bio- (life),bio- (life), -ology (the study of), -ology (the study of), patho- (disease)patho- (disease)

Weights and MeasuresWeights and Measures Metric system – Metric system –

universally used by the universally used by the scientific community – scientific community – based on the power of based on the power of 1010

Needed to determine Needed to determine and record accurate and record accurate measurementsmeasurements

ExamplesExamples Weight - Weight - gramgram

kilogram = 2.2 lb; 28.4 grams = 1 ozkilogram = 2.2 lb; 28.4 grams = 1 oz Volume - Volume - literliter

liter = 1.057 qt; 30 milliliters = 1 fluid ounce; 1 liter = 1.057 qt; 30 milliliters = 1 fluid ounce; 1 ml = 20 dropsml = 20 drops

Length - Length - metermetermeter = 39.3 in; 2.54 cm = 1 inmeter = 39.3 in; 2.54 cm = 1 inA little longer than a yard stickA little longer than a yard stick

Metric systemMetric system milli- 1/1000milli- 1/1000 centi- 1/100centi- 1/100 deci- 1/10deci- 1/10 gram, liter, metergram, liter, meter deka- 1 x 10deka- 1 x 10 hecta- 1 x 100hecta- 1 x 100 kilo- 1 x 1000kilo- 1 x 1000

Metric – metric ConversionsMetric – metric ConversionsConversions made by moving the decimal Conversions made by moving the decimal

point point Eg .001km = 1m = 1000mmEg .001km = 1m = 1000mm

Base

Gram/Meter/Liter

Kilo Hecta Deka deci Centi Milli

k h da d c m

Unit conversionUnit conversion1 in = 2.54 cm1 in = 2.54 cmA meter is a little longer than 3 feet (1 A meter is a little longer than 3 feet (1

yard)yard)A liter is about the size of a quartA liter is about the size of a quart1 kg = 2.2 lbs1 kg = 2.2 lbs

10 kg dog weighs 22 lbs10 kg dog weighs 22 lbs

TemperatureTemperature Americans use the Fahrenheit scaleAmericans use the Fahrenheit scale Science uses Celsius Science uses Celsius Conversion formula is:Conversion formula is:

C = 5/9(F – 32)C = 5/9(F – 32)

Celsius (centigrade) scaleCelsius (centigrade) scale Temperatures you should know:Temperatures you should know:

0 corresponds to 32 F (freezing)0 corresponds to 32 F (freezing)4 corresponds to 36 F (refrigerator)4 corresponds to 36 F (refrigerator)22 corresponds to 72 F (room temp)22 corresponds to 72 F (room temp)37 corresponds to 98.6 F (body temp)37 corresponds to 98.6 F (body temp)82.2 corresponds to 180 F (cagewash) 82.2 corresponds to 180 F (cagewash) 100 corresponds to 212 F (boiling)100 corresponds to 212 F (boiling)

ChemistryChemistry The interaction of The interaction of moleculesmolecules and the recombination of and the recombination of

their their atomsatoms Atoms are the fundamental materials which make up Atoms are the fundamental materials which make up

the universethe universe Atoms combine to form moleculesAtoms combine to form molecules

Important elementsImportant elements Carbon (C)Carbon (C) Oxygen (O)Oxygen (O) Hydrogen (H)Hydrogen (H) Phosphorus (P)Phosphorus (P) Nitrogen (N)Nitrogen (N) Calcium (Ca)Calcium (Ca) Sodium (Na)Sodium (Na) Iron (Fe)Iron (Fe)

Important MoleculesImportant MoleculesSome elements are naturally joined in Some elements are naturally joined in

pairspairsOxygen OOxygen O2 2 ( 21% of air)( 21% of air)Nitrogen NNitrogen N22

Carbon Dioxide – COCarbon Dioxide – CO22

Water – HWater – H22OOSalt (Sodium Chloride) - NaCl Salt (Sodium Chloride) - NaCl

Chemistry Prefixes/SuffixesChemistry Prefixes/SuffixesMono - oneMono - oneDi – twoDi – twoTri- ThreeTri- ThreeOxide – OxygenOxide – OxygenHydro – HydrogenHydro – Hydrogen

BiochemistryBiochemistry The study of chemical reactions in living The study of chemical reactions in living

organismsorganisms HomeostasisHomeostasis- the balance of these chemical - the balance of these chemical

reactions, which is an active state - important for reactions, which is an active state - important for health and for good datahealth and for good data Diet, lack of water, drug overdose, high tempuratures Diet, lack of water, drug overdose, high tempuratures

can affectcan affect Digestion, metabolism, and toxicity all involve Digestion, metabolism, and toxicity all involve

chemical reactions in the bodychemical reactions in the body

Acids, bases, and pHAcids, bases, and pHAcidified water – small amount of HCL Acidified water – small amount of HCL

(Hydrochloric acid)(Hydrochloric acid)Limits the growth of microorganismsLimits the growth of microorganisms

pH measures the concentration of pH measures the concentration of hydrogen ions hydrogen ions Many hydrogen ions - acidicMany hydrogen ions - acidicFew hydrogen ions – alkaline (basic)Few hydrogen ions – alkaline (basic)Scale 0-14Scale 0-14

Water – 7 Water – 7 (neutral)(neutral)

Low numbers Low numbers – acidic– acidic

High numbers High numbers - basic- basic

Acids and basesAcids and basesSubstances with a non-neutral pH can be Substances with a non-neutral pH can be

corrosivecorrosiveWear protective eyewear and glovesWear protective eyewear and glovespH on either end are very corrosivepH on either end are very corrosiveMeasured with a special meter or pH Measured with a special meter or pH

paper which changes color according to paper which changes color according to the pHthe pH

DilutionsDilutionsReduce the concentration or “strength” of Reduce the concentration or “strength” of

a liquida liquid