K101 LAB EXERCISE 6
CELLULAR RESPIRATION AND FERMENTATION
All living organisms have a constant need for cellular energy, and have
to collect, store, release and use ATP energy.
The major metabolic pathway by which a
cell breaks down macromolecules and releases the energy to the cell is called
Energy contained within the C-H bonds of carbohydrates or other macromolecules is transferred to
ATP during respiration.
This stored energy can be transferred later to power a wide variety of
cellular reactions by
Cellular respiration may be
, depending on the availability of O
, high-energy macromolecules like glucose are broken down in a series
of metabolic steps.
breaks glucose down into two molecules of pyruvate.
enters the mitochondria, where enzymes of the (2)
strip all the hydrogen atoms from
the pyruvate, releasing CO
The hydrogen ions (H+) and their associated electrons pass through a
series of mitochondrial membrane carriers called (3) the
Electron Transport Chain
, where they
are ultimately captured by
, forming water (H
O) and ATP via a process called (4)
For aerobic respiration of glucose, the overall equation is
O + ~36-38 ATP
Given the equation above, you may be able to spot at least four ways cellular respiration could
Consumption of glucose
(or another sugar)
2. Consumption of O
3. Production of CO
Release of ATP energy during cellular respiration.
In this K101 lab, we will measure the two most straightforward of the options above:
relative volume of
by germinating seeds and by the bacteria present in milk, and the
during both aerobic respiration and alcoholic fermentation in yeast.
is an anaerobic process for ATP production that produces ethanol or other waste
products from glucose, releasing only 2 ATP per glucose, plus in some cases a large quantity of CO
Fermentation is an important means of energy production for manya living organisms,
particularly many bacterial and yeast species.
Objectives: After this lab, you should be able to
metabolism, phosphorylation, glycolysis,
the overall equation reaction for aerobic respiration
two ways to measure O
two ways to measure CO
What is the purpose of Phenol Red, Methylene Blue, and KOH pellets in the
experiments we perform today?
4. New Techniques:
Set-up and use, and analysis of data from respirometers and fermentation