In this free course we explore proteins and how they are the 'doers' of the cell. They are huge in number and variety and diverse in structure and function, serving both the structural building blocks and the functional machinery of the cell. Just about every process in every cell requires specific proteins. The basic principles of protein structure and function which are reviewed in this course are crucial to understanding how proteins perform their various roles.

After studying this course, you should be able to:

• define and use each of the terms printed in bold in the text
• describe the different levels of protein structure and their interdependence
• explain how steric limitations determine secondary structure in polypeptides
• describe, using examples, the relationship between protein structure and function
• understand the significance of domains in protein function and how they have arisen.