1.B Scientific Method Review

A farmer is attempting to grow the largest apple for the state fair. She is trying different fertilizers on the apple trees to see how big the apples grow. What is the independent variable?

• The state fair

• The size of the apples

• The different fertilizers

• The apple tree

A student wants to know what type of hair shampoo cleans their hair best. They have three different types of shampoos - one that they usually use and two that they are testing out. They are going to see how clean their hair is by counting the days before it becomes greasy after washing. What is the dependent variable?

• Types of shampoo

• Number of days until hair is greasy

• The shampoo they usually use

• Clean hair

A scientist is testing the effect of pH on the enzyme lipase. Lipase is found in bacteria, which have a pH of 7. Lipase makes oil break apart and become dissolved by water. The scientist tests lipase at a pH of 3, 5, 7, 9, and 11 and measures how much oil is left in the water after lipase is added. What is the control group?

• ph 7

• Lipase

• How much oil is left

• Amount of water