Scientific Method Vocabulary

Observations Any information collected with the senses. The skill of describing scientific events.

Inference Conclusions or deductions based on observations . The process of drawing a conclusion from given evidence.

Tracks like these are common in parts of New England and in the southwestern United States. What do you OBSERVE? What can you INFER?

Now what do you think?

Infer what happened based on your observations.

Critter Lab

Sewer Rats

Title Should be asked or stated at the beginning of every experiment. Should be answered in your conclusion not at the beginning. The effect of _________ on __________. Example: What is the effect of weight on a paper airplane?

Hypothesis (plural – hypotheses) Special kind of prediction How to write a hypothesis Use an If, Then statement IF the independent variable changes, THEN the dependent variable changes This type of sentence shows what the IV will do to the DV

Mobius Lab

Independent Variable (also called the Manipulated Variable) What you are testing in an experiment The cause Purposely changed

Dependent Variable (also called the responding variable) What you are measuring in an experiment The Effect

Constant Materials in an experiment that are the same in both the control group and the experimental group This never changes If it did that would make 2 independent variables = NOT GOOD

Unchanged throughout experiment Control Used for comparison No treatment Unchanged throughout experiment

Control

Your Procedure must be Procedure In a step by step format Detailed Reproducible Written like a recipe!!

Tasty Solution

Materials 3 Hershey’s Kisses and a stop watch

Procedure Place one of the kisses in your mouth. DO NOT chew, and DO NOT move your tongue around. Record the time it takes for this candy piece to dissolve. Place a second kiss in your mouth. DO move it around in your mouth but DO NOT chew. Repeat step 2 Place a 3rd kiss in your mouth. This time move it around in your mouth as you chew.

Let’s Start our Short Report…. Make a title… (The effect of …. On ….) Write a hypothesis (If….then….) Complete the Experimental Design Summary. IV (Levels and Trials) DV 4 Constants Control

Title The effect of chewing the on the rate chocolate melts.

Now what do you do? What type of data/observations would be collected with this experiment? Make your observations. Why did you get the results you did?

Science Skills: Variables Self Check Click to test yourself

A variable is something that can vary or change A variable is something that can vary or change. What are the variables in this statement? The time it takes to run a 10 km race depends on the amount of training the runner does. Click to check your answers

What are the variables in this statement? The temperature of water is measured at different depths in a lake. Click to check your answers

What are the variables in this statement? The more water a plant gets, the taller it will grow. Click to check your answers

What are the variables in this statement? The number of puppies in a litter is determined by the weight of the mother dog. Click to check your answers

What are the variables in this statement? The Texas A & M Extension Service has been counting the number of coyotes in Bexar County. Will the number of coyotes have any effect on the rabbit population? Click to check your answers

The time it takes to run a 10 km race depends on the amount of training the runner does. The independent variable is the amount of exercise. The dependent variable is the time it takes to run a 10 km race. It is not enough to say just “time” or “training” – you must describe the I.V. and tell how the D.V. is measured. Click for another question

The temperature of water is measured at different depths in a lake. The independent variable is the depth of the lake. The dependent variable is the temperature of the water. Click for another question

The more water a plant gets, the taller it will grow. The independent variable is the amount of water. The dependent variable is the height of the grass. Click for another question

The number of puppies in a litter is determined by the weight of the mother dog. The independent variable is the weight of the mother dog. The dependent variable is the number of puppies in the litter. Click for another question

The Texas A & M Extension Service has been counting the number of coyotes in Bexar County. Will the number of coyotes have any effect on the rabbit population? The independent variable is the number of coyotes. The dependent variable is the rabbit population.

Qualitative data Data recorded as an observation Example – the substance has a sweet taste

Quantitative data Data that is recorded in numbers. Example – 3 inches tall

Help with the Penny Lab Cohesion Surface Tension The force between particles in a substance that works to hold it together Surface Tension Water molecules have bonds that hold them together. At the surface of the water, the molecules hold on to each other even more tightly because there are no molecules pulling on them from the air above. As the molecules on the surface stick together, they form an invisible "skin" called surface tension.

Tables and Graphs Every lab should have your data represented in a table and a graph – THEY ARE NOT THE SAME!!

The Pirate Ship

DRY MIX D – Dependent R – Respondent Y – Y axis M – Manipulated I – Independent X – X axis

TAILS Every Graph Should have T – Title A – Axis Labels I – Intervals L – Labels S - Scale

What kind of graph should I use? Line graph – change over time Bar graph – comparison Scatter plot – shows trends Pie chart or circle graph – shows % Picture Graph – uses words or pictures to represent data

Results Summary Summarize your data in one sentence. Shows Trends. Example… The bigger the coin the more drops of water the coin would hold.

Conclusion – Answer these questions in a paragraph… What was the purpose of the experiment? What were the major findings? Was the hypothesis supported by the data? How did your findings compare to your classmates? What happened that you did not expect? Why do you think this happened? How would you improve this experiment next time? What recommendations do you have for further study?

2 kinds of Research Descriptive Based on observations Examples Dissection Making Models Observing Wild Animals Experimental The manipulation and control of variables

Testing Meds. Vocab Trial – a try – should have as many as possible in an experiment Sample Size – the number of people or subjects in an experiment Placebo – a “fake medicine” used as a control – contains no drugs – usually made of sugar Trade-off - Giving up one thing in favor of another

Clinical trials must have… 1 – Consent or permission from the subject 2 – Compensation or payment for time 3 – the subject must be informed of all risks involved