measurement and data collection
Post on 17-Jan-2016
Embed Size (px)
DESCRIPTIONMeasurement and Data Collection. Pre-AP Biology. Bellwork. You are making a 10% gelatin solution by adding 10 g of gelatin to 100 mL of water and heating to 70 o C. What measurement tools would you use to make this solution? Be ready to share. Objectives. - PowerPoint PPT Presentation
PRE-AP BIOLOGYMeasurement and Data Collection
Bellwork**You are making a 10% gelatin solution by adding 10 g of gelatin to 100 mL of water and heating to 70oC. What measurement tools would you use to make this solution?Be ready to share
ObjectivesDefine the international system of unitsCalculate conversions between metric units Identify scientific tools in the laboratory used for measurement
Purpose**Your experimental results will not mean very much if you dont have a way to attach numbers or non-opinion descriptions to them. The numbers collected must be expressed in units that have the same meaning world-wideScientists have developed tools to assist in data collectionProper organization of the data allows the scientist to determine what the data really means.
International System of Units-Metric SystemScientists use the metric or SI systems of units for the measurement of physical quantities-length, volume, and massThis system of measurement is used world-wideThe metric system is a decimal system of measurement that is scaled on multiples of 10Prefixes are used in front of the units to indicate powers of ten
Metric ConversionsWhen converting between metric units, follow these rulesAlways convert to base units firstEx. To convert cmkm must first convert cm to m then to kmMake conversions using the prefix definition Ex. Use the conversion 1 cm = 102 m rather than 1 m = 100 cm
ExampleConversion of 6.5 km to mStart with what?
Why do I need to learn this method?You need to fill your swimming pool with your garden hose. The hose releases 1L of water per minute. Your pool holds 1000 kLof water. How long will it take to fill your pool?
Can you answer this by moving the decimal point?
ExampleConversion of 6.5 km to mm
Practice Problem-complete on note-taker435 mL L
Practice Problem-complete on note-taker5.39 g mg
Measurement tools used in Biology
Reading a Meter StickMeter Stick major scale division represent centimetersEach cm is further divided into minor scale divisions-0.1 cm or 1 mm divisions
Reading volume in a graduated cylinderGraduated cylinder is marked off in equal units of volumesUsually they are graduated in mLsMost graduated cylinders haveMajor scale divisions associated with numbersMinor scale divisions between the numbersRead the volume at the bottom of the meniscus
Use of balance for determining massIn this class, an electronic balance will be used for measuring massZero the balance by hitting the Tare button before each measurementPlace object on stainless steel trayRead the value for massIf you get the tray dirty, please clean it off
Closure ActivityName two measurement tools discussed in the notes today and explain how they are used in measurement.
Constructing well organized Data Tables
Example of a Good Data Table-**Effect of fertilizer on plants
DateHeight in cm of plantAppearance of leaves4/5/1110Leaves are green and there are 2 areas of light green new leaves4/6/1110All leaves are green and there are 3 areas of light green new growth4/7/1111The plant has 3 areas with light green leaves. The leaves appear to be larger4/8/1113Plant is more spread out and has 5 areas of light green leaves4/9/1116Plant has 5 areas of light green leaves
Think-Pair-ShareExamine the example data table. Write down key characteristics of a data table on your note-taker.Share with a partner
Data table characteristics**TitleClear labelsDatesColumn/row labelsUnits are includedEasy to viewStraight linesAll data can be displayed
Minute Paper- think back to the bellworkYou have one minute to write down qualitative and quantitative data in the form of a data table that you might take on the new species of plant
Be prepared to share.
***3. Think-pair-shareteacher presents a questionteacher gives wait time for student to form answerteacher instructs students to share their answer with a partnerteacher calls on non-volunteers to share with the class* 29. Minute paper or Quick Writeteacher provides a prompt from the lessonstudents have one minute to write down a summary of the key pointsstudents compare with a partnerteacher uses a strategy to check all*