130 likes | 268 Views
Aim : How can we review Scientific Method and Laboratory Techniques? Do Now : Begin answering questions on the review sheet. H.W.: Complete the review sheet for homework. Steps of the Scientific Method. Definition : A process that is used to logically solve a problem. Problem Observations
E N D
Aim: How can we review Scientific Method and Laboratory Techniques? Do Now: Begin answering questions on the review sheet. H.W.: Complete the review sheet for homework
Steps of the Scientific Method • Definition: A process that is used to logically solve a problem. • Problem • Observations • Research • Hypothesis • Experiment • Results • Conclusion
Data and Sample Size • Written records of observations • In other words NUMBERS. VS • The bigger the sample size, the better the results or conclusion will be. Why?
Gets normal treatment Used for comparison Gets the substance or the treatment you are testing Controlled experiment • Control group • Experimental group
Variables (factors that change) • Independent (Manipulated) Variable– what the scientist controls • Dependent (Responding) Variable – changes because of the independent variable In our experiment, can you identify the independent & the dependent variables?
Tables and Graphs • Independent variable • Dependent variable x-axis y-axis Independent (X) Dependent (Y) • Determine the independent/dependent variables in this example?
How are the independent and dependent variable related in the graph below? • As the temperature • increases, then the • pressure increases
How do we measure volume? • You measure volume of a liquid in a graduated cylinder by reading the bottom of the curve called the meniscus
A- 6mm B- 12mm or 1.2cm C- 22mm or 2.2c m D- 37mm or 3.7c m E- 56mm or5.5cm F- 67 mm or 6.7cm G- 75 mm or 7.5cm How do we measure Distance
Cell Cultures • Why does a doctor stick a swab inside your mouth? • Cultures are used to grow bacteria. The jelly at the bottom is called agar.
Chromatography • Why do scientists use chromatography as a laboratory technique. • Separates mixtures by size. Smaller pigments migrate further up the paper.
State Lab • Explain what happens to the glucose, starch, and iodine. • Why? • Why did we use iodine in this experiment. Glucose + Starch • After several hours, the smaller GLUCOSE will DIFFUSE across the dialysis tubing membrane, while the larger STARCH will not. • IODINE (which is small) will also diffuse across this membrane turning the cell BLUE. Iodine
State Lab How did this change occur? • Salt water was added, causing water to diffuse out of the cell