The variable the scientist controls, or the 'if' portion of the hypothesiss.

• dependent variable

• control group

• independent variable

• experimental group

A company wants to test a new dog food that is supposed to help overweight dogs lose weight. 50 dogs are chosen to get the new food, and 50 more continue their normal diets. After one month, the dogs are checked to see if they lost any weight. What is the independent variable in this scenario?

• amount of dog food

• type of dog food

• the weight of the dog

• the breed of the dog

A cow is given a growth hormone and then compared to another cow that was not given a growth hormone.  Both cows were weighed at 2 years. What is the dependent variable in this scenario?

• the amount of hormone given

• the weight of the cow

• the type of cow tested

• the type of hormone tested

What is a controlled variable?

• The variable being tested or changed by the scientist, also known as the manipulated variable.

• The variable that the

  scientist is measuring or

  observing, also known as the responding variable.

• The variables that the scientist keeps constant, which allows them to attribute the results to the independent variable alone.

Tags

NGSS.MS-PS2-2

How many independent variables should we change when conducting an experiment?

• 1

• 2

• 3

• As many as we want

An experimental design included references from prior experiments, materials and equipment, and step-by-step procedures. What else should be included before the experiment can be started?

• a set of data

• a conclusion

• safety precautions to be used

• an inference based on results

A student was comparing preserved specimens of three plant species, X, Y, and Z, in a classroom. Which statement is an example of an observation the student could have made and not an inference?

• the leaves produced by plant X are 4 cm across and 8 cm in length.

• plant Y has a large purple flowers that open at night.

• plant X produces many seeds that are highly attractive to finches.

• the flowers of plant Z are poisonous to household pets.

Which science tool would you use to measure the volume of a liquid?

• Graduated cylinder

• Ruler

• Balance

• Thermometer

If you spill or break something during an experiment, what is the FIRST thing you should do?

• Tell the teacher.
• Clean it up. 
• Cover it with a paper towel.
• Leave it for someone else.

Record the following in cm

• 1.0

• 1.2

• 1.25

• 1.250

• 1.30