Metabolism

The end result of digestion is the absorption of nutrients into the body where they can be used in various ways. Metabolism refers to any chemical reaction that occurs within the body and involves either breaking nutrients down for energy (catabolism), or storing nutrients in tissues (anabolism). Breaking nutrients down for energy is typically accomplished in human beings with the use of oxygen (aerobic respiration). However, nutrients can be broken down via fermentation in the absence of oxygen (anaerobic respiration). In this lab, you will examine the simplified metabolism of yeast, which generate energy anaerobically using fermentation.

In Part 1 of this exercise you will determine fermentation rates of yeast under 4 different conditions. Yeast give off carbon dioxide as they ferment. You will use the amount of carbon dioxide production as your measure of fermentation rate (i.e., the more carbon dioxide produced, the higher the fermentation rate). In Part 2, you will determine fermentation rates of yeast using 6 different types of substances that differ in thier nutrient composition and, therefore, in the rate at which yeast can metabolize them.

Part 1: Requirements for Fermentation

Part 2: Evaluating Rates of Fermentation

Metabolism Lab Worksheet