BIO 181 Lecture 4.3

Lecture 4.3: Enzymes


Life is defined in part by metabolism. Although we typically define that concept by the types of chemical reactions that occur, from another viewpoint, metabolism is all about energy management. In the previous lecture we studied what energy is and is not. Managing energy in essence means we extract free energy from chemical compounds mainly to drive endergonic reactions. But, what machinery does that? The answer is, enzymes do that. Here we begin our study of enzymes before moving to our first metabolic system–the simplest one known, which powers living creatures in the deepest recesses of the ocean.


  1. Read Sections 8.3 through 8.5 of the textbook.
  2. Download Lecture 4.3 slides.
  3. Watch and take notes on video 4.3.1, Enzymes.
  4. Watch and take notes on video 4.3.2, Deep-Sea Metabolism.
  5. Complete the questions on Study Guide 4.3. (Not to be handed in.)


After completing the activities, log into Canvas, launch BIO 181 and complete Lecture 4.3 Quiz.

This entry was posted in Uncategorized. Bookmark the permalink.