Transcript AP Biology Ch. 9 Fermentation and Quiz Ppt

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Glycolysis produces 2 ATP and 2 NADH when
glucose is split into 2 pyruvate (pyruvic acid)
Fermentation will break down pyruvic acid
further without oxygen, producing a small
amount of ATP.
Summary of Glycolysis:
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Fermentation consists of glycolysis plus reactions
that regenerate NAD+, which can be reused by
glycolysis
Two common types are alcohol fermentation and
lactic acid fermentation
Alcohol is
produced
by plant
cells
Lactic acid is
produced by
animal cells
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
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In plant cells without oxygen, the pyruvate is
broken down by fermentation.
This process produces CO2 and alcohol, along
with a small amount of ATP
This process is used in baking and to produce
alcoholic beverages.
Without O2 present, pyruvate produced in plant
cells will ferment. It will give off CO2 (which
causes bread to rise) and ethanol (alcohol).
Without O2 present in animal cells, pyruvate will be broken
down to form lactate (lactic acid). This is the substance that
makes muscles burn during intense exercise. Humans can
break down the lactic acid further to produce a little more
ATP when O2 is scarce.
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Some yeasts and bacteria also produce lactic
acid from fermentation.
Lactic acid from these sources produces yogurt
and cheese.
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Both processes break down glucose to release
energy.
Fermentation produces 2 ATP per glucose,
Aerobic Cellular Respiration produces 38 ATP
Electrons from glucose go to either lactic acid
or alcohol in fermentation
Electrons from glucose go to Oxygen in
Cellular Respiration.
Which is better???
Obligate Anaerobes Vs. Facultative Anaerobes:
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Obligate anaerobes carry out fermentation or
anaerobic respiration and cannot survive in the
presence of O2
Yeast and many bacteria are facultative
anaerobes, meaning that they can survive using
either fermentation or cellular respiration
In a facultative anaerobe, pyruvate is a fork in the
metabolic road that leads to two alternative
catabolic routes
Glucose
Facultative Anaerobes
CYTOSOL
Glycolysis
Pyruvate
No O2 present:
Fermentation
Ethanol
or
lactate
O2 present:
Aerobic cellular
respiration
MITOCHONDRION
Acetyl CoA (if present)
Citric
acid
cycle
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Glycolysis occurs in nearly all organisms
Glycolysis probably evolved in ancient
prokaryotes before there was oxygen in the
atmosphere
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Catabolic pathways funnel electrons from many
kinds of organic molecules into cellular
respiration
Carbohydrates: Glucose is broken down
Proteins: Broken down to amino acids—these go
to either glycolysis or the Citric Acid Cycle
Fats: Broken down to glycerol
(goes to glycolysis) and fatty
acids (made into Acetyl CoA).
Proteins
The
Catabolism
of Various
Molecules
from Food:
Amino
acids
Carbohydrates
Sugars
Glycerol
Glycolysis
Glucose
P
NH3
Fats
Pyruvate
Acetyl CoA
Citric
acid
cycle
Oxidative
phosphorylation
Fatty
acids
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Feedback inhibition is the most common
mechanism for control
If ATP concentration begins to drop, respiration
speeds up; when there is plenty of ATP,
respiration slows down
Control of catabolism is based
mainly on regulating the
activity of enzymes at strategic
points in the catabolic pathway
Glucose
The Control
of Cellular
Respiration
AMP
Glycolysis
Fructose-6-phosphate
–
Stimulates
+
Phosphofructokinase
–
Fructose-1,6-bisphosphate
Inhibits
Note how
the
presence of
too much
ATP will
block
reactions
from
proceeding
Inhibits
Pyruvate
ATP
Citrate
Acetyl CoA
Citric
acid
cycle
Oxidative
phosphorylation
Question 1
A. What is this
molecule?
C.What is this molecule?
2
ATP
B.Name of process?
+
2 NADH
Glucose
D. Where does this process occur?
2
Pyruvate
Question 2:
A. What is the name of this type of reaction?
B. Which molecule has been reduced?
C. Which molecule has been oxidized?
Question 3:
Enzyme
Enzyme
ADP
P
Substrate
++
ATP
Product
A. This reaction is phosphorylating ADP to
form ATP. What is phosphorylation?
B. What type of phosphorylation is this
(substrate-level or oxidative)?
Question 4:
CYTOSOL
MITOCHONDRION
NAD+
NADH + H+
2
1
A. What
molecule is this?
3
CO2
Coenzyme A
C. What is happening in this process?
B. What
molecule is
this?
Qu. 5:
A. What
molecule
is this?
CO2
NAD+
CoA
NADH
+ H+
C. Where is
this series
of reactions
occurring?
D. What are
the
products of
this
reaction?
Acetyl CoA
CoA
CoA
FADH2
B. What is
the name
of this
series of
reactions?
3 NAD+
3 NADH
FAD
E. Where
did most of
the energy
go?
2 CO2
+ 3 H+
ADP + P i
ATP
Question 6:
A. What are
these
purple
“blobs”?
B. What is
their
purpose?
C. Where are
they
located?
D. What is
the final
electron
acceptor?
NADH
50
2 e–
NAD+
FADH2
2 e–
40

FMN
FAD
Multiprotein
complexes
FAD
Fe•S 
Fe•S
Q

Cyt b
30
Fe•S
Cyt c1
I
V
Cyt c
Cyt a
Cyt a3
20
10
2 e–
(from NADH
or FADH2)
0
2 H+ + 1/2 O2
H2O
Question 7:
A. What is the
name of this
molecular
structure?
B. Where would
you find one
of these?
C. What is its’
job?
D. How does it
work?
INTERMEMBRANE SPACE
H+
Stator
Rotor
Internal
rod
Catalytic
knob
ADP
+
P
i
ATP
MITOCHONDRIAL MATRIX
Question 8: What in the world is going on here?????
H+
H+
H+
H+
Protein complex
of electron
carriers
Cyt c
V
Q


ATP
synthase

FADH2
NADH
2 H+ + 1/2O2
H2O
FAD
NAD+
ADP + P i
(carrying electrons
from food)
ATP
H+
1 Electron transport chain
Oxidative phosphorylation
2 Chemiosmosis
2 ADP + 2 Pi
Question 9:
Study the two
sets of
reactions
shown here:
A. Which one
occurs in
plants?
B. Which one
occurs in
animals?
C. What is the
name of these
reactions?
Glucose
2 ATP
Glycolysis
2 Pyruvate
2 NAD+
2 NADH
+ 2 H+
2 CO2
2 Acetaldehyde
2 Ethanol
(a) Alcohol fermentation
2 ADP + 2 Pi
Glucose
2 ATP
Glycolysis
2 NAD+
2 NADH
+ 2 H+
2 Pyruvate
2 Lactate
(b) Lactic acid fermentation
Glucose
Question 10: Which is better for ATP production: Oxygen
or no oxygen and why?
Glycolysis
CYTOSOL
Pyruvate
No O2 present:
Fermentation
O2 present:
Aerobic cellular
respiration
MITOCHONDRION
Ethanol
or
lactate
Acetyl CoA
Citric
acid
cycle