Review

This part of the experiment serves as a basis of comparison:

• control group

• Independent variable

• dependent variable

• data

This variable in an experiment is the one being deliberately changed by the scientist.

• dependent variable

• independent variable

• data

• control group

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music. In this investigation, the independent variable is ...

• type of plant

• the amount of sunlight

• the type of music

• the type of liquid

A student wants to test the effects of type of exercise on heart rate. What is the dependent variable?

• time of day exercise occurs

• amount of exercise

• heart rate

• type of exercise

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music. In this investigation, what are the controlled variables?

• type of plant, amount of music, and sunlight

• plant growth

• water, apple juice, milk

The graph below shows atmospheric carbon dioxide levels since the year 1880.Which of the following conclusions can be drawn from this graph

• Atmospheric carbon dioxide levels are responsible for global temperature change.

• Atmospheric carbon dioxide levels have been rising at about the same rate for the past century.

• Atmospheric carbon dioxide levels have remained the same over the past century.

• Atmospheric carbon dioxide levels have been rising at an increasingly higher rate as the past century has progressed.

In order to be accepted, a scientific theory must be

• based on the results of a single experiment

• widely tested and supported by extensive data

• in line with all previous historical ideas

• controversial and cause debate

An experiment was carried out to determine whether drinking caffeinated soda increases pulse rate. The pulse rates of two groups of people at rest were measured. Group A was then given caffeinated soda and group B was given caffeine-free soda. One hour after drinking the soda, the pulse rates were measured. The participants in the experiment were all the same age, and they were all given the same amount of soda. The dependent variable in this experiment is the

• type of soda given to each group

• amount of soda given to each group

• pulse rate of each group

• age of participants in each group

A testable question should include what two things?

• A hypothesis and question

• A question and a dependent variable

• An independent variable but no dependent variable

• An independent variable and a dependent variable

___ are the first organisms to colonize an area and begin the process of ecological succession.

• foundational organisms

• introductory organisms

• primary organisms

• pioneer species