Unit 1 | Lesson 1: Scientific Inquiry

Why is the scientific method important for conducting experiments and making discoveries?

A scientist is testing whether a new type of fertilizer will increase plant height compared to plants without the fertilizer. Which of the following is the alternative hypothesis?

A biologist wants to test if the amount of light affects the rate of photosynthesis in a certain plant species.

Which of the following is the null hypothesis?

A biology class is testing whether listening to classical music affects plant growth. They divide identical plants into two groups:

Group A: Plants kept in silence

Group B: Plants exposed to classical music for 2 hours a day

Which is the control group?

Identifying the Independent Variable
A scientist wants to test whether different amounts of sunlight affect the number of tomatoes a plant produces. She plants tomato plants in identical soil and gives them the same amount of water, but places them in areas with 4, 6, or 8 hours of sunlight each day.

Which is the independent variable?

Identifying the Dependent Variable
A student is testing whether the temperature of water affects how quickly sugar dissolves. They place sugar cubes in water at 10°C, 25°C, and 40°C, and time how long it takes for each to fully dissolve.

Which is the dependent variable?