Unit 1: Introduction to Biology
Biology is the study of life. While biologists have made great strides in discovering things on earth, there are still many new things to learn. The first fundamental questions are: What is Life? What does it mean to have life? These inquiries are essential to the discoveries that biologists find every day. With such a vast scope of information, biologists must organize these discoveries that will stand the test of time. In this unit, we introduce the major topics that biologists study and the theories they use and apply to their work.
Completing this unit should take you approximately 4 hours.
Upon successful completion of this unit, you will be able to:
- list the basic characteristics of life that are common to all living things;
- list the levels of organization of life and characteristics of each level; and
- describe the steps of the scientific method and the importance of using the scientific method in research.
1.1: Introduction to Biological Inquiry
Science is knowing. Scientists search for knowledge through inquiry, which is a way of questioning and explaining phenomena that occur in nature. Let's begin by exploring how biologists and researchers use the scientific method in the scientific inquiry of life.
Read this discussion about the nature of science, scientific inquiry, and hypothesis testing.
Watch this lecture, which discusses the unifying themes of biology. We will cover the last portion of the lecture which describes the chemistry and properties of water in Units 2 and 3. Note that the lecturer later apologizes for saying the "thymus" enlarges when she had meant to refer to the "thyroid" when describing a goiter in the neck at the 30-minute mark of the video.
1.2: Biology Systems and Water
There are some core properties that are found in all living things. Since it is unreasonable to memorize every biological discovery, biologists focus on unifying themes that every discovery falls under. Earth, the only known biosphere, is made of 75 to 80 percent water. Since the properties of water are conducive to life on earth, scientists search for life when they discover the presence of water on other planets.
The characteristics of living organisms (evolutionary adaptation, growth, reproduction, etc.) differentiate living and non-living things. The fundamental difference between a living thing and a dead thing is metabolism. Metabolism is the chemistry of life. It includes all of the chemical reactions occurring in all of the cells that make up an individual organism. Life ceases when the chemical reactions of metabolism cease. Read this chapter to explore and identify the common characteristics of living organisms.
These characteristics of life include adaptation, cell structure, growth and development, homeostasis, metabolism, reproduction, and responsiveness to the environment.
Unit 1 Assessment
Take this assessment to see how well you understood this unit.
- This assessment does not count towards your grade. It is just for practice!
- You will see the correct answers when you submit your answers. Use this to help you study for the final exam!
- You can take this assessment as many times as you want, whenever you want.