Unit 3: Biological Molecules
All organisms contain the organic biological molecules – carbohydrates, proteins, lipids, and nucleic acid – that are essential to life. Having an understanding of the structures and functions of these molecules will help you understand what organic molecules our body needs to function properly.
Completing this unit should take you approximately 5 hours.
Upon successful completion of this unit, you will be able to:
- list the characteristics of water that make it important to life as we know it;
- explain the characteristics that are necessary to make something alive;
- recognize the structure of the four major biological macromolecules;
- describe the functions of the four major biological macromolecules;
- indicate the monomers and polymers of carbohydrates, proteins, and nucleic acids; and
- describe the four levels of protein structure.
3.1: Water and Organic Molecules
Water is one of the most important compounds on Earth, since no living organisms can survive without water. Understanding the unique properties of water is very important for the study of biology. Read this section, and be sure to complete the multiple choice and free response questions at the end of the section.
3.2: Acids and Bases
The hydrogen ion concentration of biological systems can be measured using the pH scale. Watch this lecture to learn about the pH scale and how it affects biological systems.
Read this section and complete the "Did I Get This" activity at the end of the section. How can the pH measurements of acidic and basic solutions affect living organisms?
Watch this lecture to learn about acids and bases, and how they relate to the concentration of hydrogen ions in a solution.
3.3: Biological Macromolecules
Watch this lecture to review biological macromolecules and their role in biological organisms.
Biological macromolecules are the raw ingredients that allow living cells to exist and survive. Read the introduction, and then click "next" to also read sections 3.1 to 3.5, "Synthesis of Biological Macromolecules", "Carbohydrates", "Lipids", "Proteins", and "Nucleic Acids". Make sure to also complete the multiple choice and free response questions at the end of each section
Unit 3 Assessment
Take this assessment to check your understanding of the materials presented in this unit.
Notes:
- There is no minimum required score to pass this assessment, and your score on this assessment will not factor into your overall course grade.
- This assessment is designed to prepare you for the Final Exam that will determine your course grade. Upon submission of your assessment you will be provided with the correct answers and/or other feedback meant to help in your understanding of the topics being assessed.
- You may attempt this assessment as many times as needed, whenever you would like.