Download NO OXYGEN!

BIOLOGY
Chapter 4.6
Fermentation
SB3. Students will derive the relationship
between single-celled and multi-celled organisms
and the increasing complexity of systems.
a. Explain the cycling of energy through the
processes of photosynthesis and respiration.
b. Compare how structures and function vary
between the six kingdoms (archaebacteria,
eubacteria, protists, fungi, plants, and animals).
c. Examine the evolutionary basis of modern
classification systems.
d. Compare and contrast viruses with living
organisms.
KEY CONCEPT
Fermentation
allows the
production
of a small
amount of
ATP without
oxygen.
OH NO! NO OXYGEN!
WHAT DO WE DO?
•
If no oxygen is available, cells can obtain
energy through the process of anaerobic
respiration.
• A common anaerobic process is
fermentation.
•
Fermentation is not an efficient process
and results in the formation of far fewer
ATP molecules than aerobic respiration.
There are two primary
fermentation processes:
1. Lactic Acid
Fermentation
2. Alcohol
Fermentation
Lactic acid fermentation occurs
when oxygen is not available.
For example, in muscle tissues during rapid and
vigorous exercise, muscle cells may be depleted
of oxygen. They then switch from respiration to
fermentation.
The pyruvic acid formed during glycolysis is
broken down to lactic acid and energy is released
(which is used to form ATP).
Glucose → Pyruvic acid → Lactic acid + energy
GLYCOLYSIS
AEROBIC
ANAEROBIC
When oxygen levels are
too low aerobic animals
become anaerobic and
produce lactic acid. this
causes muscle cramps.
LACTIC ACID
FERMENTATION:
PYRUVIC ACID
BECOMES LACTIC ACID
•The process of lactic acid fermentation replaces
the process of aerobic respiration so that the cell
can have a continual source of energy, even in the
absence of oxygen.
•However this shift is only temporary and cells
need oxygen for sustained activity.
Lactic acid that builds up in the tissue
causes a burning, painful sensation.
Alcohol fermentation occurs in yeasts and
some bacteria.
Pyruvic acid formed during glycolysis is
broken down to produce alcohol and
carbon dioxide and is released (which is
used to form ATP).
FERMENTATION
ALCOHOL
LACTIC ACID
ALCOHOLIC
FERMENTATION:
PYRUVIC ACID
BECOMES ALCOHOL
AND CO2
Fermentation allows glycolysis to
continue.
• Fermentation allows glycolysis to
continue making ATP when oxygen
is unavailable.
• Fermentation is an anaerobic
process.
–occurs when oxygen is not available
for cellular respiration
–does not produce ATP
Glucose → Pyruvic acid → alcohol + carbon dioxide + energy
• Fermentation allows glycolysis to
continue making ATP when oxygen is
unavailable.
• NAD+ is recycled to glycolysis
• Lactic acid fermentation occurs in
muscle cells.
– glycolysis splits glucose into two
pyruvate molecules
– pyruvate and NADH enter fermentation
– energy from NADH converts pyruvate into
lactic acid
– NADH is changed back into NAD+
Fermentation and its products
are important in several ways.
• Alcoholic fermentation is similar to
lactic acid fermentation.
– glycolysis splits glucose and the
products enter fermentation
– energy from NADH is used to split
pyruvate into an alcohol and carbon
dioxide
– NADH is changed back into NAD+
– NAD+ is recycled to glycolysis
Fermentation is used in food
production.
–yogurt
–cheese
–bread
Fermentation is used in food
production.
– Yogurt
- Soy Sauce
– Cheese
- Vinegar
–Bread
- Olives/
Pickles
– Beer/ Meade
- Wine/ Ale
– Sauerkraut
- Malt
Lactic Acid or Alcohol
Fermentation?
EITHER WAY
ANAEROBIC
RESPIRATION ONLY
PRODUCES 2 ATP.
AEROBIC
RESPIRATION
USES OXYGEN TO
MAKE MUCH MORE
ATP