Chapter 1, Problem 16A

Summary Introduction

To differentiate:

Between the given terms

Introduction : Biologists follow the same basic steps to do research and answer queries. These are called scientific methods. They conduct experiments, collect data, make hypothesis and gather evidences. They make inferences based on prior experiences. Controlled experiments involve a control group and an experimental group.

Answer to Problem 16A

Control group- It includes a group that is used for comparison.

Experimental group- It includes a group that is exposed to the factor being tested.

Explanation of Solution

Scientists gather information from various experiments. This information is called data. They then analyze the data and decide if the data supports the hypothesis. The experiments are conducted over and over again to gather more data. When a biologist conducts an experiment, he or she investigates a phenomenon in a controlled setting in order to testify a hypothesis. They form two groups to test the variable/factor; a control group and an experimental group.

Control group- It includes a group that is used for comparison without the factor.

Experimental group- It includes a group that is exposed to the factor being tested.

For example in the experiment with kittiwakes, the control group was not given supplements while the experimental group was given supplements. Based on the results of these two groups, the scientists inferred that the kittiwakes would have more energy to lay eggs and chicks if they were given extra feeding during nesting time.

By comparing the results of the control and experimental groups, the biologists draw conclusions about the effect of the variable.