What is the Scientific Method ?????????????

Definition ► Scientific method: basic steps that scientists follow in uncovering facts and solving scientific (or any) problems

Basic Parts of Scientific Method ► Stating the problem ► Gathering information ► Suggesting an answer for the problem ► Performing an experiment to see whether the suggested answer makes sense ► Recording and analyzing the results of experiments or other observations ► Stating conclusions

The 5 Steps of Scientific Method ► Recognizing the Problem (Observe) ► Researching the Problem (Gather) ► Forming a Hypothesis ► Testing the Hypothesis through experimentation ► Drawing Conclusions Stop Stop

More Vocabulary ► Hypothesis-a statement that can be tested (educated guess) ► Experiment-testing a hypothesis using a series of steps with controlled conditions ► Variable-something that causes changes observed in an experiment ► Control- is a standard for comparing results (something that never changes) ► Data- the recorded facts or measurements from an experiment ► Theory-is a hypothesis that has been tested again and again by many scientists, with similar results each time

Using the Scientific Method The Rattlesnake Experiment

Recognizing the Problem ► What invisible trail does a rattlesnake follow in tracking down its bitten prey?

Researching the Problem ► What invisible trail do you think that the snake is following?  Don’t just guess think about what is taking place and what some of the possibilities could be. (make an educated guess)

Still Researching by Gathering Information ► You can not truly or effectively answer this question without gathering important information or “KNOWN FACTS” about snakes!!!!!

Still Gathering Information ► A rattlesnakes eyes are only sensitive to visible light ► A pair of organs located under the eyes detect invisible light in the form of heat ► A rattler’s tongue “smells” certain odors in the air ► The sight or smell of an unbitten animal does not trigger the rattler’s tracking action

Form a Hypothesis ► After the snake bites its victim, the snake follows the smell of its own venom to locate the animal.

Perform an Experiment ► Drag a dead mouse that has been struck and poisoned by a rattlesnake along a curved path on the bottom of an empty cage ► Place the snake in the cage ► The snake follows the exact trail that has been laid out ► Drag an unbitten dead mouse along the path ► The snake seems disinterested

Important Parts of the Experiment ► What were the controls in this experiment? ► The same snake was used ► The same tank was used ► The snake was given the opportunity to bite the mouse ► Can You think of any other controls? ► How many controls can you have in an experiment.

Important Parts of the Experiment ► There can be only one variable per experiment to sustain validity. ► What was the variable in this experiment? ► The snake not having the opportunity to strike it’s prey.

Recording and Analyzing Data ► Do the experiment many times ► Record the data ► The more the experiment is preformed the more valid it becomes.

Conclusion ► The scent of venom was the only factor that could cause a rattlesnake to follow its bitten victim.