Cellular Resp

Cellular Respiration and Fermentation

Abstract:

This paper describes how cellular respiration and fermentation can be acquired by using yeast, corn syrup and malt extract. There is a detailed experiment in that shows how you can acquire these results yourself by measuring the levels of CO2 produced by the reaction. Yeast which is a cell that does not require oxygen to go about cellular respiration is used to make our own alcoholic fermentation in a easy to understand experiment.

Introduction:

Let’s discuss fermentation first. This process uses a substance, in this case corn syrup/Malt Extract, along with a catalyst (yeast) in order to produce energy (ATP). As a bi-product of this reaction carbon dioxide (CO2) is released. Cellular respiration occurs in most living organisms and is the source of energy, yielding up to 38 ATP per glucose. Fermentation is responsible for only two of those ATP.

In most living organisms, cellular respiration occurs in two conditions. When oxygen is present, it is considered aerobic. Where oxygen is lacking it is anaerobic. Aerobic cellular respiration produces far more energy than anaerobic. Anaerobic cellular respiration occurs with no oxygen and is mainly used in bacteria, although fermentation is also anaerobic.

First let’s focus on Aerobic cellular respiration. Aerobic respiration has four stages: glycolysis, transition reaction, Krebs cycle (Citric Acid cycle), and the electron transport chain. It requires lots of oxygen and is the main source of ATP for all organisms, producing up to 38 ATP per glucose. The food we eat is broken down into glucose so that it can be used in cellular respiration. Glycolysis occurs in the cytoplasm of a cell where a metabolic pathway breaks down glucose through a series of enzyme-catalyzed reactions and yields two ATP. As a result, glucose is transformed into pyruvate which then enters another metabolic pathway called the Krebs cycle. In the Krebs cycle, some reactions release...