Unit 1 | Lesson 1: Scientific Inquiry

Multiple Choice

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

• It helps organize thoughts and ensures reliable results.

• It makes experiments more fun.

• It guarantees all experiments will succeed.

• It is only used by professional scientists.

Multiple Choice

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?

• The new fertilizer has no effect on plant height.

• The new fertilizer will increase plant height compared to plants without it.

• The plants without fertilizer will grow faster than the plants with fertilizer.

• The new fertilizer will cause plants to die.

Multiple Choice

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?

• Different light levels will change the rate of photosynthesis.

• The rate of photosynthesis will be highest in bright light.

• Light intensity has no effect on the rate of photosynthesis.

• Plants in low light will produce less oxygen than those in bright light.

Multiple Choice

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?

• Group A — Plants kept in silence

• Group B — Plants exposed to classical music

• Both groups

• Neither group

Multiple Choice

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?

• The type of soil used

• The number of tomatoes produced

• The amount of water given

• The number of hours of sunlight each plant receives

Multiple Choice

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?

• The size of the sugar cubes

• The time it takes for the sugar to dissolve

• The temperature of the water

• The type of sugar used

With a partner, on a sheet of paper, complete the following: