so in this video we’re going to have a brief overview of what a laboratory format looks like is a very prescriptive format that’s used when you’re reporting your scientific data we’re going to go through the parts step by step you’ll be doing your first laboratory report on the beat lab so you begin by placing your name in the upper left hand corner and any lab partners name as well second thing you put is your date and that is the date the experiment was conducted or the dates the experiment was conducted it is not the date that you write the lab report third is the title oftentimes you can simply copy what’s on the handout that you receive in class but sometimes it’s kind of fun to try being a little creative with whatever the experiment is step 4 or part 4 is writing the hypothesis so practice these in class a little bit a hypothesis is a possible explanation of something you’ve seen or tried to figure out or it can be a question or it can be a guess about how things work most conveniently you can phrase things as if then if I walk into the street at rush hour I will get hit by a car that would be a testable hypothesis but probably not a life-affirming one next is the procedure and that’s a step-by-step description of how you did the experiment the way to know if you’ve done a good job is could you hand this procedure off to your five-year-old nephew who can read and have her or him be able to follow the process step-by-step next is a sketch and the sketch usually shows the setup so that again your nephew or your niece could look at this and actually put together the different parts in the experiment to get it started very importantly all of the pieces in your sketch should be labeled where appropriate sizes of things like 50 millimeter flasks should be included or ten millimeter a test tube those details are important the heart of the experiment is the results section and the results section consists of two things it consists of your data and then it consists of a discussion of how the data relates to the hypothesis now this is never where raw data shows up your data should at this point be organized into a table or it should be presented as a graph or some other visual that allows the reader to see the patterns that you’re discussing or the absence of patterns if you don’t find one once you’ve organized your data the next part of the results is to discuss how the data or the patterns in the data support your hypothesis or disprove your hypothesis so you summarize the data and then you explain why it works or doesn’t work and then finally you discuss possible sources of error what are some of the unintended variables in your experiment that could have affected the data in such a way that it doesn’t really reflect the experiment as you think it should human error is usually not a good fallback and finally you state the conclusion and that’s a very brief summary in that you restate your hypothesis and that is what was it you were trying to prove and then a summary of the data and how it proves or disproves your hypothesis and then finally one or two sentences that suggest how you would refine this experiment or do another experiment to further refine understand or disprove your hypothesis that is a laboratory report you’ll be doing one for the beat lab and then there’s two or three others that are scheduled throughout the year will expect you to write up through to the data section ahead of time and will actually ask you to turn that in so we can grade it and make comments and then once your lab is completed will expect you to do the results section in the conclusion and we’ll go over that in class experimental design involves being knowledgeable about three different variables the independent variable the dependent variable and the controlled variable so let’s look at those in a little more detail control variables are the factors that you want to keep fixed throughout the experiment it might be the temperature of the room where the experiment is happening it might be the amount of light falling on the experiment it might be the concentration of some ingredient it might be the number of animals or plants involved but these are things that you do not want to vary through the experiment so they are controlled the next variable is the independent variable that’s the one thing that you’re going to change so that you can observe its effect so this is the thing that you are going to manipulate it could be pH it could be concentration it could be number of animals it could be the absence of the presence of a predator there are any number of independent variables depending on what you’re looking at the dependent variable that third variable is a factor that you’re going to measure so for example with enzymes the independent variable may be the amount of enzyme present because you’re looking at how fast something gets catabolized broken down so the dependent variable would measure how much of the product accumulates another example ol independent variable might be the amount of sunlight that is required for plants to grow so the independent variable would be the sunlight which you control the dependent variable might be a measure of height of the plant so the control group usually does not receive a treatment okay there is no change in the independent variable it’s really the baseline that you’re going to compare your experimental group against the experimental group receives the treatment it’s the one where the independent variable has been changed how many times should you repeat your experiment it really depends there are times when two or three or four repetitions is adequate there are times when 10 20 30 repetitions is necessary unfortunately in high school you only get to do things once if you’re really lucky you get to do them twice so when we say you’re collecting data there’s really two kinds of data there’s qualitative data and there’s quantitative data qualitative data is dismissed a lot of times but it’s absolutely essential and that is the observations they don’t contain numbers but they’re like colors they could be changes in texture anything that’s a visual or even something that could smell for instance bacteria when they reach a certain concentration in a petri dish smell a different way than when they’re not there quantitative data as the adjectives suggest is numbers so here you’re measuring things like how many colonies how much does it cover how many animals are there how high is the plant that’s quantitative data so let’s do a little experimental design practice here you’re thinking the further you sit from dr. G the less chance you will get caught using your phone so think about a hypothesis what might be your if-then statement so my if-then statement might be if I sit far away from dr. G just back of the back row then I will not get caught using my phone so the independent variable here the thing that’s going to vary is where I sit close or far away the dependent variable is the number of times I get caught and the control group in this case might be people in the very back row the experimental group would be anybody between dr. G and that back row so what am I looking at am I looking at qualitative data or am I looking at quantitative I’m really counting so that’s quantitative data and think about if we were to graph this suppose each day I came in and I sat in a different seat a different distance and I did this over a period of three months what would that graph look like because I’m going to graph distance from dr. G on the x axis because that’s my independent variable that’s a thing I have control over and the dependent variable on the y-axis is going to be how many times I get caught and you would expect that that graph would have a slope such that the highest incidence would be closest to the origin and the lowest would be farther away so we’re going to do a beat lab and first we’re going to just play around and see what happens when we expose beats to stuff that’s about as meticulous as I’m going to get in describing it and then you’re going to design your own experiment in which you’re going to look at an experimental group and you’re going to decide what you’re going to measure in this case I’m hoping that you will decide to do both qualitative and quantitative measurements and then you’re going to have to decide on your control your independent in your dependent variables there should be a lot of fun it’s always a surprise especially as the building ages so good luck and we’ll be talking more about this in class