Introduction to Biology

Important Vocabulary

• observation

• inference

• hypothesis

• null hypothesis

• controlled experiment

• independent variable

• dependent variable

• control group

• data

• theory

• bias

• biology

• sexual reproduction

• asexual reproduction

• DNA

• metabolism

• stimulus

• homeostasis

• evolve

Your goal for the end of this unit is to be able to say, “I CAN…”

• Use the steps of the scientific method in an experiment

• Identify the aspects of a controlled experiment

• Define the terms: control group, experimental group, independent variable, dependent variable

• Identify and list the properties of life needed in order for something to be considered living

• Define and establish the difference between the terms: observation and inference

Example Questions:

1. If my experimental hypothesis were ‘Eating cheese before bed affects the number of nightmares you have’, what would the null hypothesis be?

• Eating cheese before bed gives you more nightmares.

• Eating cheese before bed gives you fewer nightmares.

• Eating cheese is linearly related to the number of nightmares you have.

• The number of nightmares you have is not affected by eating cheese before bed.

The correct answer is The number of nightmares you have is not affected by eating cheese before bed. This is because the null hypothesis is the opposite of the alternative hypothesis and so usually states that an effect is absent.