Process Skills & Safety Review

7th Grade Science

Do you have control?• The independent variable is the type of soil. • The dependent variable is the plant growth. • The controlled variable is the type of plant,

sun exposure or amount of water.

It’s a process…• Steps to the scientific process: – Identify a problem– Collect information– Suggest a hypothesis– Design and perform an experiment– Make measurements and collect data– Interpret data– Draw conclusions

Say what???• Process skills are the diverse

ways in which scientists study the natural world.

• A scientific theory is able to explain a large number of ideas, because it has been tested multiple times.

• If scientists expect something to happen the same every time under a given set of conditions, it is called a scientific law.

Controlled Experiments are Cool

• Manipulated variable: surface type

• Responding variable: bounce height

• Inference drawn: rubber balls will bounce higher on harder surfaces.

It’s better to be safe than sorry

• Following the teacher’s instructions are the safety measure you should ALWAYS use during a lab experiment.

• If you don’t understand the lab procedure, you should ask the TEACHER.

• Follow lab safety procedures to avoid injury.

Scientists, skills, and safety

• If a scientist is watching a dog play, they are using their OBSERVATION skills.

• After the teacher hands out a copy of the lab experiment, you should read the directions.

• Following directions and being safe are the most important skill in any lab experiment.

Data, & Controlled Experiments

• Measuring is a method of taking quantitative data.

• A controlled experiment is designed to test a hypothesis.

• A scientist changes the independent or manipulated variable during a controlled experiment.

• In a controlled experiment, a scientist will only change one variable at a time.

• In a controlled experiment, there are at LEAST two groups!

Kittens• If a scientist counts the number of kittens, he

has collected scientific data.

• If a scientist explained that all the kittens had dark fur, he would be giving qualitative data.

• The number of kittens near the school is an example of quantitative data.

MIX & DRY• MIX– Manipulated– Independent– X axis

• DRY– Dependent– Responding– Y axis

Controlled Experiment Examples

• A scientist hypothesizes that the temperature at which a chicken egg is incubated will determine whether the chick will be male or female. If the scientist conducts a controlled experiment, temperature would be called the Manipulated/Independent variable

Controlled Experiment Examples• A scientist conducted an experiment to

determine how the amount of salt in water affects the number of plants that can live in the water. In the experiment, the manipulated or independent variable is THE AMOUNT OF SALT IN THE WATER.