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ATP
2009-2010
ATP
2009-2010
Synthesis
Reproduction
Active Transport
Movement

Glucose
ATP
 Animals
eat these organic molecules
to release that energy
as ATP ( Adenosine Triphosphate )
Cells break down GLUCOSE
and release the energy that they
contain in their chemical bonds.
The energy in glucose is converted into
a form of energy the organism
can use ►ATP
 ATP

(adenosine triphosphate)
the primary source of energy for the cell
The HIGH ENERGY BOND is in the
TERMINAL PHOSPHATE BOND
P
P
P
Adenosine triphosphate (ATP)
H2O
P
i
+
P
P
Figure 8.9Inorganic phosphate Adenosine diphosphate (ADP)
Energy
1. ATP releases small quantities of energy
which are appropriate for most cell activities
2. ATP’s energy can be released with just one
reaction
3. ATP can be recycled
Hydrolysis of ATP
ATPase
H2O + ATP
→
ADP + P + ENERGY
Cellular Respiration is used to produce ATP
molecules from ADP
ATPase
ENERGY + P + ADP → ATP + H2O
The Recycling of ATP

In cellular respiration, glucose is
broken down gradually in a series of
enzyme-controlled steps


If respiration involves the use of O2 the process is aerobic
If no O2 is used - the process is
anaerobic
Anaerobic respiration takes
place in the cytoplasm of the
cell
Aerobic respiration takes
place in the Mitochondria of
the cell
1. Glycolysis (occurs in cytoplasm
2. Krebs cycle (occurs in mitochondria)
3. Electron Transport Chain (occurs in the
mitochondria)
( AKA – Oxidative Phosphorylation )
Overall Reaction
C6H12O6 + 6 O2
6 CO2 + 6 H2O + 36 ATP
1. The Respiration Pathway begins with
a process called glycolysis ( Breaking
Glucose)
2. High Energy Electrons are released
3. These electrons are used to make ATP

Oxidation: an atom or molecule loses a
high energy electron (Glucose)

Reduction: an atom or molecule gains a
high energy electron
( Coenzymes )
OIL - RIG


High energy electrons (e-) are released from
glucose (Oxidation)
They then are passed to NAD+ (Nicotinamide
Adenine Dinucleotide) which gains electrons (
Reduction )
NAD+ + 2e- → NADH


High energy electrons (e-) are released during
Krebs cycle
They then are passed FADH2 (Flavine Adenine
Dinucleotide) which gains electrons (
Reduction )
 NADH
and FADH hold the electrons
until they can be used in the
Electron Transport Chain
The Respiration Pathway begins with a
process called glycolysis
“splitting of sugar”



involves a reactions which break Glucose
into 2 molecules of Pyruvate
THIS TAKES PLACE IN THE CYTOPLASM
NO OXYGEN NEEDED

Preview to Glycolysis


glucose is a very stable molecule
glycolysis requires an investment of 2 ATP
molecules to get the process started

glucose is a very stable molecule
glycolysis requires an investment of 2 ATP
molecules to get the process started

2 ATP + C6H12O6  2 pyruvate + 4 ATP

2 NAD+


2 NADH+
NET GAIN OF ATP: _____ Net Gain of NADH______
glycolysis animation
Glycolysis Video
The
pyruvic acid from glycolysis is used by the
mitochondria for the aerobic phases of cell
respiration
Only
10 % of energy stored in Glucose is used
during Glycolysis

Mitochondria have an external membrane and
an inner membrane with numerous folds
called cristae
The
cristae project into the gel-like matrix

electron micrograph:
Krebs cycle (occurs in the matrix of the
mitochondria) – Needs O2
electron transport (occurs in the cristae of
the mitochondria) – Needs O2


British biochemist
Won Nobel Prize in 1953
for the discovery of the
Citric acid cycle or Krebs
cycle in 1937

During the Krebs cycle, pyruvic acid is broken
down and releases carbon dioxide


Pyruvic acid must be converted into a
two carbon molecule: Acetyl CoA to enter the
Krebs cycle
3 carbon
2 carbon
What is released?________

Acetyl Co-A is converted into citric acid

Citric acid is broken down in series of steps


Electrons are transferred to NADH and a
FADH2 (Flavine Adenine Dinucleotide)
CO2 is released as a waste product

Net gain per glucose: Two Turns of the Cycle
2 ATP
6 NADH
2 FADH2
6 CO2 are released as a waste product




Carbohydrates: cells use glycogen supplies
stored in the liver
Proteins: amino acids are fed into the Krebs
cycle.
Fats: Excess fats stored in adipose tissue
are digested into glycerol (which enters
glycolysis) and fatty acids (which enter the
Krebs cycle).
Proteins and lipids can form many ATP but
waste products are toxic

Krebs cycle animation



Uses high-energy electrons stored in NADH
and FADH2 from the Krebs cycle to convert
ADP into ATP
Each FADH2 produces - 2 ATP
Each NADH produces - 3 ATP

Electron transport chains are proteins in in
the inner membrane of the mitochondria


High energy electrons are passed from one
protein to the next
This energy is used to pump H+ ions into the
inter-membrane space, making it positively
charged

The inner membranes of the mitochondria
contain protein spheres called ATP synthases

As H+ ions escape through channels into
these proteins, the ATP synthases spin

Each time it rotates the enzyme grabs an ADP
and attaches a phosphate, forming ATP

ATP Synthase Animation
INTERMEMBRANE SPACE
H+
H+
H+
H+
H+
H+
A rotor within the
membrane spins
clockwise when
H+ flows past
it down the H+
gradient.
H+
A stator anchored
in the membrane
holds the knob
stationary.
H+
ADP
+
Pi
Figure 9.14
MITOCHONDRIAL MATRIX
ATP
A rod (for “stalk”)
extending into
the knob also
spins, activating
catalytic sites in
the knob.
Three catalytic
sites in the
stationary knob
join inorganic
Phosphate to ADP
to make ATP.


At the end of the electron transport chain is
an enzyme that combines electrons from the
electron chain with hydrogen ions and
oxygen to form water
Oxygen serves as the final electron acceptor

electron transport animation



Glycolysis is the breakdown of glucose to
pyruvate. 2 ATP generated.
The Krebs Cycle breaks down pyruvate to
carbon dioxide and water. 2 ATP generated.
NAD and FAD accept H+ ions and electrons
to be carried to the electron transport
chain.
Electron transport chain processes the H+
ions and electrons to generate 32 ATP.
Oxygen is the final electron acceptor.
Electron shuttles
span membrane
CYTOSOL
MITOCHONDRION
2 NADH
or
2 FADH2
2 NADH
2 NADH
6 NADH
Glycolysis
Glucose
2
Pyruvate
2
Acetyl
CoA
+ 2 ATP
+ 2 ATP
by substrate-level
phosphorylation
Maximum per glucose:
Figure 9.16
Citric
acid
cycle
by substrate-level
phosphorylation
About
36 or 38 ATP
2 FADH2
Oxidative
phosphorylation:
electron transport
and
chemiosmosis
+ about 32 or 34 ATP
by oxidative phosphorylation, depending
on which shuttle transports electrons
from NADH in cytosol

Great Review - Crash Course
36 ATP molecules produced from each
molecule of glucose
CO2 and H20 are waste products
Great Cellular Respiration Review
 Also
called - Fermentation
Two Ways:
Used by organisms that lack the enzymes
necessary to utilize O2
Other organisms are aerobic but revert to
anaerobic respiration if O2 is not available

Cell respiration stops with glycolysis

2 ATP + C6H12O6  2 pyruvate + 4 ATP
→ also used to produce soy sauce from
soybeans, to pickle cucumbers, and to
produce sausage, pepperoni, and salami
→ used in dairy industry to manufacture
cheese, butter, sour cream and yogurt
(produces sharp or sour taste)


Animal cells utilize fermentation if O2 is not
available
Lactic acid is produced
→ associated with muscle soreness and
fatigue

Yeast (a fungus) can perform aerobic
or anaerobic respiration
→ used by brewing and baking industries
Fermentation of Cheese