Objective 1 TEK 1 The student, for at least 40% of the time, conducts field and

laboratory investigations using safe, environmentally appropriate, and ethical practices.

(A) Demonstrate safe practices during field and laboratory investigations.

TEK 2 The student uses scientific methods during field and laboratory investigations.

(A) Plan and implement investigative procedures including asking questions formulating testable hypotheses, and selecting equipment and technology.

(B) Collect data and make measurements with precision and accuracy.(C) Organize, analyze, evaluate, make inferences, and predict trends

from data.(D) Communicate valid conclusions.TEK 3 The student uses critical thinking and scientific problem solving to

make informed decisions.(A) Analyze, review, and critique scientific explanations, including

hypotheses and theories.(B) Draw inferences based on data related to promotional materials for

products and services.

Objective Topic 10th Grade

11th Grade

1 Safety, Scientific Process, Graphs, Charts

17 17

2 Cells, DNA, Cell processes 11 83 Kingdoms, Ecosystems, 11 84 Chemistry 8 115 Physics 8 11Total 55 55

You have to get 29 questions out of 55 to pass this test. Data shows that students who answer at least10 of17 correctly from objective 1usually pass.

1. Never eat or drink in the lab.

2. Remain alert at all times.3. Keep your area free of

clutter.4. Follow both written and

verbal directions.5. Students may not work

alone.6. Remain at your

workstation.7. Always wear goggles and

other safety items.8. Secure all loose items.9. Hair should be pulled

back.10. Contacts are no allowed.

1. Never pipette by mouth.2. Never use broken glassware.3. Hot glass looks like cool

glass.4. Hot glass does not go in

water.5. Test tubes should be heated

with the mouth away from people.

6. Always poor acid into water.7. Never touch electrical devices

with wet hands.8. Never smell a chemical

directly.9. Never poor unknown

chemicals down the sink.10. Never return unused

chemicals to the original container.

Caustic or corrosive- Will corrode or eat away metal, skin, or other substances. Volatile- Evaporates quickly, may form dangerous vapors.Flammable (may ignite)- will catch on fire or explode easily. Ventilation- removing contaminated air and brining in fresh air.

Safety Terms:

                                                          

                        

Scientific Lab

EquipmentCertain materials are included under the fair use exemption of the U.S. Copyright Law and have been prepared according to the multimedia

fair use guidelines and are restricted from further use.

Credits: Clip art from Microsoft Design Gallery

Presentation originally compiled/created by Dtresten.HIS.2001

Adaptations by to Tcrannie, Mneel, Kcope, and S.Dillon

Lab Equipment-Review Uses.ppt

Balance (not a triple beam)

• To measure mass (weight) of substances or objects accurately

graduated cylinder (graduate)

• To measure volume of liquids accurately

SI Ruler(“Metric” is slang.)

• To measure the lengths of solid objects accurately

SI thermometer

• To measure temperature accurately

oC

magnifying glass (hand lens)

• To make objects appear larger than they are

Bunsen burner

• To heat substances (with a flame)

hot plate

• To heat substances using electricity, not a flame.

ring stand with clamp and ring

• To hold containers away from a heat source (such as fire) during an experiment

safety goggles

• To protect eyes against burns or cuts

microscope

• To view specimens that are too small to see with the naked eye

Molecular Expressions Microscopy Primer: Virtual Microscopy: Interactive Java Tutorials

slide

• To hold a specimen (sample) for viewing through a microscope

cover slip

• To cover a specimen (or sample) on a slide

medicine dropper(eyedropper)

• To drop small amount of liquids

forceps

• To pick up small items that you should not touch

Petri dish

• To grow bacteria and other tiny living things

test tube

• To hold liquids and chemicals during experiments (investigations)

test tube rack

• To hold test tubes during an investigation. (After cleaning, test tubes can be placed upside down to dry.)

test tube tongs

• To hold test tubes over heat or away from your body

test tube brush

• To clean the insides of test tubes after investigations

Erlenmeyer flask

• To hold liquids• NOT used to measure

accurately

Florence flask

• Used to hold liquids• NOT used to measure

accurately

beaker

• To hold, pour, or estimate liquids

• NOT used to measure substances accurately

tongs

• To pick up large objects that you should not touch (e.g., hot containers, flasks of acids, etc.)

Funnel

To pour liquids from one container to another without spilling anything

stirring rod

• To mix chemicals and hot liquids together (like a spoon)

litmus paper

• To determine whether a liquid is an acid or a base

Accurate measurement When measuring distance: You will have a ruler on the side of your formula sheet. USE IT if you are asked to measure distance on a map or a length. You must measure accurately and precisely. The wrong answer choices will test to see if you do.

Measure the length of a tile.Measure the width of your folder.

When measuring liquids: Wear goggles! Use a graduated cylinder or graduated pipette. Beakers are not accurate!!! Read the bottom of the meniscus (curved line formed by the water) on a graduated cylinder or burette. Check your units. Do they increase or decrease? Do they go up by 1.0, 0.1, or 5.0? Read carefully.

Volume of irregular objects: Use a graduated cylinder to take volume by water displacement .

14 mL

When massing solids: Wear goggles! Use a weigh boat or paper. Subtract out the weight of the container or paper to zero the balance. Clean up spills.

Read the balance with the weigh paper.

Read the balance with the weigh paper and chemical.

Now subtract.

Experimental set-up/Scientific Method: When scientists begin an experiment they use the steps of the Scientific Method. You will be asked to do many of these steps on the test. The Problem (in the form of a question) that the scientists will try to answer, must be logical and based on data or observations. A prediction called a Hypothesis is next. It must be a testable statement that you could gather data to prove. (You can’t measure which is the “prettiest”, “strongest”, or “best”.)

You must control an experiment. You can test only one variable at a time. (How does the amount of water effect plant growth? Keep the light, containers, soil and plants the same.) Controls are kept the same in all trials. A Control Group is the set-up that isn’t changed. (One plant gets the normal amount of water!). The independent variable is the thing you change (amount of water). The dependent variable is the result of the change you made(height of plant in cm.).

Controls: Light, type of plant, amount of soil, pot, temperature.

Independent variable: Amount of water given in mm. Dependent variable: Plant growth in cm.

The Conclusion must be supported by the data and results you gather. To be valid, each experiment needs a large sample size (grow 2000 plants in each experiment) and must be repeated many times in order to prove the Hypothesis (grow 2000 plants 100 times). If you are collecting samples, in an experiment, do it randomly. Don’t take them all from one place.

Yes! No!

Reading Graphs and Making Calculations

Some TAKS questions ask students to analyze graphs or do basic math calculations to solve problems or draw conclusions. The Independent Variable on a graph is on the X-axis. The Dependent variable is on the Y-axis.

Line graphs represent change over time. The steeper the slope of a line, the faster the change in time is occurring.

Pie graphs represent %’s of a whole.

Pictographs use symbols to represent numbers.Always check keys and legends to accurately read units and labels on graphs. Bar graphs represent numbers of individuals or items in each category.

You may be asked to calculate a %. To find a %, divide the # of items you have by the total #, then multiply by 100. Carefully read product labels and claims. Make sure you can separate fact from opinion.