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Learn essential lab safety rules to prevent accidents caused by carelessness, haste, and disregard for safety protocols. Follow guidelines meticulously for a secure laboratory environment.
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Unit 0: Intro to Biology Ms. Burriesci OLH
LAB SAFETY • Accidents DO HAPPEN; caused by carelessness, haste, and disregard for lab safety rules that have been set in place.
LAB RULES PART 1 • Do not perform experiment without teachers permission. • Read and follow lab directions and procedures carefully. • Be able to locate fire extinguisher/eye wash/fire blanket/first aid kit. • Wear goggles when heating, working with chemicals…such as acids and bases, and during dissections. abcnews.go.com sourcing.community.mfg.com alertms.nl umedsupply.com
LAB RULES PART 2 • Tie back long hair when dealing with flames or various harsh chemicals. • Clean lab bench top of all unnecessary materials such as books, bags, clothing, etc. before starting to work. • ABSOLUTLY NO EATING OR DRINKING IN THE LAB ROOM. • NEVER taste or eat lab materials. If you are instructed to smell something, do so by “wafting” some of the vapors towards your nose.
LAB RULES PART 3 • Report lab accidents IMMEDIATLEY to the teacher. • Handle all chemicals carefully. • NEVER LOOK DIRECTLY DOWN A TEST TUBE; view from the side ONLY. Never points towards your neighbor either. • Never take reagent bottles to work bench…always acquire chemicals through beakers, test tubes, or paper. TAKE ONLY SMALL AMOUNTS. Easier to get more than to waste excess! doubleimage.co.uk
LAB RULES PART 4 • Do not return unused chemicals to stock bottle. • Dispose of any broken glass, unused chemicals, and waste products of a reaction only directed by the teacher. • Keep flammable materials away from flames. • Know the correct procedure to prepare acid solution. (ALWAYS ADD ACID SLOWLY TO WATER). • DO NOT use dissection tools until you have been given proper instruction. gaudette-insurance.com
LAB RULES PART 5 • After completing an experiment…clean and put away your lab equipment. WASH YOUR HANDS before you leave the lab. • NEVER removelab materials and equipment from the lab room.
Measuring in Biology [The Metric System]
The Metric System • The metric system is the world standard for measurement. • All of the measurements done in this course will use the metric system.
Metrics UNITS METER GRAM LITER DEGREES CENTIGRADE
Metric Conversions • Meters, grams, and liters (see the table above) form the basis for larger or smaller units. The units are named using these prefixes: Base=1 Key Units for Biology
Metric Conversions… • Same conversions will work for meter and liter. 1000g =1kg 0.1g =1 dg or 1g=10dg 0.01g =1cg or 1g=100cg 0.001g =1mg or 1g=1000mg 0.001mg=1 μg or 1mg=1000μg • Notice that each of the units in the metric system are related by a multiple of 10.
How to Convert? • Metric conversions are done by “moving the decimal point.” • When converting a large unit such as Metersto a smaller unit such as Millimeters, the decimal point is moved to the right. • When converting smaller units to larger units, the decimal point is moved to the left.
METRIC LADDER King Henry Died While Drinking Chocolate Milk
How to use Ladder Method • FIND YOUR STARTING POINT • COUNT THE “JUMPS” TO YOUR ENDING POINT • MOVE DECIMAL THE SAME NUMBER OF JUMPS…IN THE SAME DIRECTION
How to use Ladder Method • FOR EXAMPLE: • CONVERT 4 KILOMETERS TO METERS 4km=_____m Start Point End Point Move 3 places to the right!!!!!! Answer= 4,000
How to use Ladder Method • PRACTICE PROBLEM #1: Q: Convert 5cm to meters? 5cm=____m Start Point End Point Answer= .05m
Ladder Method Practice Problems 5,000 2,000 Convert the following: 1) 5 kg=_______g • 2m=________mm • 30 cm=______mm 300
Lets Practice… 2,000 • Convert the following: • 1) 2mg=______μg • 2) 300μm=________mm .300
Measuring Volume • Graduated Cylinder= used to measure volume. • When using a graduated cylinder be sure to measure from the bottom of the meniscus.
Measuring Length • A ruler is used to measure length.
Measuring Temperature • A thermometer is used to measure temperature.
Measuring Mass • A Gram Balance is used to measure mass.
Practice Measuring • Below are pictures of metric rulers. Determine the length of each? • 2.4 cm • 6 cm
Practice Measuring • Find the volume of liquid (to the nearest milliliter) in the graduated cylinders below. • 5ml • 16 ml
Precision & Accuracy • PRECISION= refers to the reliability or reproducibility of a measurement. • ACCURACY= is the closeness of the measurement to the accepted value.
Graphing • If an experiment is to be done correctly, the experiment must be performed with a control and only ONEvariable factor. All other conditions must be CONSTANT. • Once data from an experiment is collected, a graph is a convenient way to represent the data obtained.
Graphing • Data collected in an experiment is either DEPENDENT or INDEPENDENT. • Independent Variable (x-axis)= is the data the experimenter is “controlling”, usually the first set of data collected. • Dependent Variable (y-axis)= is the data that results from or responds to what the experimenter is doing.
Rules for Plotting Points • ALL GRAPHS MUST HAVE APPROPRATE TITLE. • ALL GRAPHS MUST USE ¾ OF THE GRAPH PAPER. • MUST PLOT POINTS FROM LEFT TO RIGHT. • The (x-axis) must plot the Independent variable. • The (y-axis) must plot the dependent variable.
Rules for Plotting Points NOTE: The Origin DOES NOT have to begin at ZERO!
Graphing Practice… A student was determining the temperature change of water. The temperature was measured and recorded at one-minute intervals. • Plot the given data. • Be sure to answer the questions below AFTER you have completed the graph (on the next page).
Review Questions: • Did temperature increase or decrease with time? • Is time or temperature the independent variable? Decrease Time
Unit 0: The Scientific Method Ms. Burriesci 2018-2019 OLH
The Scientific Method • This is the scientific method and ALLScientistsuse this technique to perform their experiments.
1. State the Problem/Ask Question • a problem is a question to be considered, solved or answered. Most questions to be answered are based on observations.
3. Form an Hypothesis • An explanation that accounts for a set of facts and can be tested by further investigation. It is formulated by examining observations carefully and making an “Educated Guess” as to what the outcome might be. It is a predication about the relationship between variables that can be tested.
4. Perform A Controlled Experiment • Tested under controlledconditions made to demonstrate the truth or examine the validity of a hypothesis. • The experiment MUST be UNBIASED in nature!!!!!!
5. Collect/Analyze Data • Experiments become more VALID if they are performed multiple times by a scientist…MANY scientists. • Uses large number of SUBJECTS. • Change ONE VARIABLE at any given time, while keeping everything else exactly the same between groups. There should always be at least two groups: EXPERIMENTAL GROUP (1 VARIABLE CHANGED) CONTROL GROUP (NOT CHANGED)