ENERGY
• The ability to perform work
• Ex: your heart muscle does
work every time it beats
• Two basic forms of energy
• Potential
• kinetic
POTENTIAL ENERGY
•Is stored energy due to an
object’s position or
arrangement
KINETIC ENERGY
• Energy of motion
• Anything that is moving
• Kinetic - “motion”
THERMAL ENERGY
•Energy that has been
transferred
•From areas that are warmer
to cooler
CHEMICAL ENERGY
•Organic compounds store
energy (potential) in the
way their atoms are
arranged.
•This is called chemical
energy
Types of Organisms
Some Organisms use sunlight to make food in
a process called photosynthesis:
These organisms are called AUTOTROPHS or
PRODUCERS.
Some organisms cannot use sunlight to make
food-they must eat instead:
These organisms are called HETEROTROPHS
or CONSUMERS.
Types of Organisms
No matter how organisms get their food
ALL get their energy FROM THE FOOD
in the SAME way.
Cellular Respiration
Cellular Respiration
Cellular Respiration is a Process in which
organisms create ATP from the food they
make or eat.
Cellular Respiration
During Cellular Respiration we take potential energy
(stored energy) called chemical energy stored in the bonds
of glucose and turn it into ATP.
ATP is called free energy because it is available to do any
type of work needed in our cells called Kinetic Energy
(energy available for work)
The amount of energy released is measure in calories or
kilocalories
The more energy a type of food can release the more
calories it has
• Before the energy can be used,
it is first transformed into a form
which the organism can handle
easily.
• This special carrier of energy is
the molecule
• adenosine triphosphate, or ATP.
•
ATP’S STRUCTURE
• An ATP molecule is composed of three
components.
• 1st - A sugar molecule called RIBOSE
• 2nd - Attached to one side of the ribose is a base (a
group consisting of linked rings of carbon and nitrogen
atoms); in this case the base is adenine.
• 3rd - Attached to the other side of the ribose is a string of
phosphates
• These phosphates are the key to the activity of
ATP.
ATP consists
of a base, in
this case
adenine
(red), a
ribose
(magenta)
and a
phosphate
chain (blue).
HOW IT WORKS
• ATP works by losing the endmost
phosphate group when instructed
to do so by an enzyme.
• This reaction releases a lot of
energy, which the organism can
then use to build proteins, contact
muscles, etc
The reaction product is
adenosine diphosphate
(ADP),
ATP
ADP
•Even more energy can be
extracted by removing a
second phosphate group to
produce adenosine
monophosphate (AMP).
AMP
• When the organism is resting and
energy is not immediately needed, the
reverse reaction takes place and the
phosphate group is reattached to the
molecule using energy obtained from
food or sunlight.
• The ATP molecule acts as a chemical
'battery', storing energy when it is not
needed, but able to release it instantly
when the organism requires it.
•
CELLULAR
RESPIRATION
CELLULAR RESPIRATION
• A catabolic, exergonic, oxygen (O2)
requiring process that uses energy
extracted from macromolecules
(glucose) to produce energy (ATP)
and water (H2O).
C6H12O6 + 6O2  6CO2 + 6H2O + energy
glucose
ATP
QUESTION:
•In what kinds organisms
does cellular respiration
take place?
PLANTS AND ANIMALS
•Plants - Autotrophs: selfproducers.
•Animals - Heterotrophs:
consumers.
MITOCHONDRIA
• Organelle where cellular respiration takes place.
Outer
membrane
Inner
membrane
Inner
membrane space
Matrix
Cristae
BREAKDOWN OF CELLULAR
RESPIRATION
• Three main parts (reactions).
1. Glycolysis (splitting of sugar)
a. cytosol, just outside of mitochondria.
BREAKDOWN OF CELLULAR
RESPIRATION
2. Krebs Cycle (Citric Acid Cycle)
a. mitochondrial matrix
3. Electron Transport Chain (ETC
a. inner mitochondrial membrane.
1. GLYCOLYSIS
• Occurs in the cytosol just outside of mitochondria.
• Two phases:
A. Energy investment phase
B. Energy yielding phase
1. GLYCOLYSIS
A. Energy Investment Phase:
Glucose (6C)
C-C-C-C-C-C
2ATP
2 ATP - used
0 ATP - produced
0 NADH - produced
2ADP +
P
Glyceraldehyde phosphate (2 - 3C)
(G3P or GAP)
C-C-C
C-C-C
1. GLYCOLYSIS
B. Energy Yielding Phase
Glyceraldehyde phosphate (2 - 3C)
(G3P or GAP)
GAP
GAP
C-C-C C-C-C
4ADP +
P
4ATP
0 ATP - used
4 ATP - produced
2 NADH - produced
C-C-C C-C-C
(PYR)
(PYR)
Pyruvate (2 - 3C)
(PYR)
1. GLYCOLYSIS
• Total Net Yield
2 - 3C-Pyruvate (PYR)
2 - ATP
2 - NADH
2. KREBS CYCLE (CITRIC ACID CYCLE)
• Location: mitochondrial matrix.
• Acetyl CoA (2Ccarbon molecule) bonds to
a 4 carbon molecule to make Citrate
(6Carbon molecule).
• It takes 2 turns of the krebs cycle to make 1
glucose molecule.
Mitochondrial
Matrix
2. KREBS CYCLE (CITRIC ACID CYCLE)
1 Acetyl CoA (2C)
OAA (4C)
Citrate (6C)
Krebs
Cycle
FADH2
(one turn)
2 CO2
3 NAD+
FAD
3 NADH
ATP
ADP + P
2. KREBS CYCLE (CITRIC ACID CYCLE)
2 Acetyl CoA (2C)
Citrate (6C)
OAA (4C)
4 CO2
Krebs
Cycle
2 FADH2
(two turns)
6 NAD+
2 FAD
6 NADH
2 ATP
2 ADP +
P
2. KREBS CYCLE (CITRIC ACID CYCLE)
• Total net yield (2 turns of krebs cycle)
1. 2 - ATP
2. 6 - NADH
3. 2 - FADH2
4. 4 - CO2
3. ELECTRON TRANSPORT CHAIN (ETC)
• Location: inner mitochondrial membrane.
• Uses ETC and ATP Synthase (enzyme) to make
ATP.
• ETC pumps H+ (protons) across
innermembrane
Inner
Mitochondrial
Membrane
3. ELECTRON TRANSPORT CHAIN
• The H+ then moves via diffusion through ATP
Synthase to make ATP.
• All NADH and FADH2 converted to ATP during
this stage of cellular respiration.
• Each NADH converts to 3 ATP.
• Each FADH2 converts to 2 ATP (enters the ETC
at a lower level than NADH).
TOTAL ATP YIELD
1.
04 ATP – glycolysis and krebs cycle
2. 30 to 34 ATP - ETC
34 to 38 ATP - TOTAL YIELD
ATP
MAXIMUM ATP YIELD FOR
CELLULAR RESPIRATION
(EUKARYOTES)
Glucose
Cytosol
Mitochondria
Glycolysis
Krebs
Cycle
2 Acetyl CoA
2 Pyruvate
2NADH
2 ATP
6NADH
2FADH2
(substrate-level
phosphorylation)
2NADH
ETC and Oxidative
Phosphorylation
2 ATP
(substrate-level
phosphorylation)
2ATP
4ATP 6ATP
18ATP
Up to 38 ATP
4ATP
2ATP
FERMENTATION
• Occurs in cytosol when “NO Oxygen” is
present (called anaerobic).
• Remember: glycolysis is part of fermentation.
• Two Types:
1. Alcohol Fermentation
2. Lactic Acid Fermentation
ALCOHOL FERMENTATION
• Plants and Fungi
C
C
C
C
C
C
2ADP
+2 P
glucose
beer and wine
2ATP
2NADH
2 NAD+
C
C
C
Glycolysis
2 NAD+

2NADH
2 Pyruvic
acid
C
C
2CO2
released
2 Ethanol
LACTIC ACID FERMENTATION
• Animals (pain in muscle after a workout).
C
C
C
C
C
C
2ADP
+2 P
2NADH
Glycolysis
2 NAD+
Glucose
2ATP
2NADH
2 NAD+
C
C
C
C
C
C
2 Pyruvic
acid
2 Lactic
acid
LACTIC ACID FERMENTATION
• End Products: Lactic acid fermentation
2 - ATP
2 - Lactic Acid molecules
ALCOHOL FERMENTATION
• End Products: Alcohol fermentation
2 - ATP
2 - CO2
2 – molecules of ethanol
QUESTION:
• In addition to glucose, what
other various food molecules
are use in Cellular Respiration?
CATABOLISM OF VARIOUS
FOOD MOLECULES
• Other organic molecules used for fuel.
1. Carbohydrates: polysaccharides
2. Fats: glycerol’s and fatty acids
3. Proteins: amino acids