3. What is the common
misconception?
Respiration is NOT……..
4. Respiration
“Controlled Release of Energy”
Production of ATP (Adenosine Triphosphate)
from organic molecules.
Occurs within the cells of ALL organisms.
5. Aerobic Cell Respiration – Requires Oxygen
Summary Equation
Glucose + Oxygen = ENERGY (ATP) + Carbon Dioxide + Water
Raw Materials Waste Products
Anaerobic Cell Respiration – Oxygen is not
used
Animals (including humans)
Glucose ENERGY (ATP) + Lactate (lactic acid)
Yeast Cells
Glucose ENERGY (ATP) + Ethanol +Carbon Dioxide
6.
7. REDOX Reactions
OXIDATIONOXIDATION
• Gain of oxygen atomsGain of oxygen atoms
• Loss of hydrogenLoss of hydrogen
atomsatoms
• Loss of electrons fromLoss of electrons from
a substancea substance
REDUCTIONREDUCTION
• Loss of oxygen atomsLoss of oxygen atoms
• Gain of hydrogenGain of hydrogen
atomsatoms
• Gain of electrons to aGain of electrons to a
substancesubstance
10. If Glucose is the Substrate Glycolysis = 1If Glucose is the Substrate Glycolysis = 1stst
Stage inStage in anyany RespirationRespiration
•THIS PATHWAY OCCURS IN THE CYTOPLASM
•LESS AMOUNT OF ENERGY IS PRODUCED
•PARTIAL OXIDATION OF GLUCOSE OCCURS, AND
DOES NOT REQUIRE OXYGENDOES NOT REQUIRE OXYGEN
•IT OCCURS IN BOTH PROKARYOTES &
EUKARYOTES
•4 Steps in Glycolysis
14. NADNAD++
= nicotinamide adenine dinucleotide= nicotinamide adenine dinucleotide
NADNAD++
and NADH are electron carriers (and co-enzymes) theyand NADH are electron carriers (and co-enzymes) they
carry electrons from one reaction to another. G3P (triosecarry electrons from one reaction to another. G3P (triose
phosphate) is oxidised NADphosphate) is oxidised NAD++
is reduced (gains 2 electronsis reduced (gains 2 electrons
and 2 hydrogens). These are carried to the electronand 2 hydrogens). These are carried to the electron
transport chain (we will see later).transport chain (we will see later).
15. STEP 4: ATPSTEP 4: ATP
formationformation
TwoTwo 33
CARBONCARBON
COMPOUNDCOMPOUND
formedformed
2 PYRUVATE2 PYRUVATE
MOLECULESMOLECULES
4 ADP4 ADP 4 ATP4 ATP
Enzymes remove the 2 phosphate groups and provide them to ADP
for ATP formation
22. Aerobic Respiration -
Overview
• Stages in the Aerobic respiration:
• Link Reaction: Pyruvate is transported into
the matrix of the mitochondria.
• Krebs cycle: carbon fragments (C2) are
progressively decarboxylated to yield ATP and
reduced coenzymes.
• Electron Transport System (Oxidative
phosphorylation in terms of chemiosmosis):
reduced coenzymes are used to generate
more ATP.
26. 1) LINK REACTION – Matrix of the
Mitochondria
• Pyruvate passes from the cytosol to the innerpasses from the cytosol to the inner
mitochondrial matrixmitochondrial matrix by active transport
Each moleculeEach molecule
ofof PYRUVATEPYRUVATE
2 CARBON2 CARBON
COMPOUNDCOMPOUND
ACETYL CoAACETYL CoA
NADNAD++
NADH + HNADH + H++
COCO22CoACoA
27. 1) LINK REACTION – Oxidative
Decarboxylation
What is the net yield of Acetyl CoA per glucose molecule?
32. 2) Kreb Cycle – Lots of Carbons!!
• Where?
• C2 = Acetyl
• C2 + C4 (oxaloacetate) = C6 (Citric Acid/Citrate)
Blue Carbons
from the
Mitochondria
Carbons from
original
glucose
molecule
33. 2) Kreb Cycle – Lots of Carbons!!
• C2 + C4 (oxaloacetate) = C6 (Citric Acid/Citrate)
• C6 oxidative decarboxylation = C5
NAD+ is
reduced
C6
decarbox
ylated to
produce
C5
34. 2) Kreb Cycle – Lots of Carbons!!
• C5
• C5 oxidative decarboxylation = C4
NAD+ is
reduced
C5
decarbo
xylated
to
produce
C4
35. 2) Kreb Cycle – Lots of Carbons!!
• C4
• Substrate level phosphorylation and electron
transport acceptors
NAD+ is
reduced
ADP
reduced
to ATP
FAD is
reduced
to
FADH2
Flavin Adenine
Dinucleotide =
electron
carrier
39. • The energy stored in NADH and FADH is used toThe energy stored in NADH and FADH is used to
generate a proton gradient across the innergenerate a proton gradient across the inner
membrane.membrane.
• The energy of the proton gradient is used toThe energy of the proton gradient is used to
make ATP (phosphorylate).make ATP (phosphorylate).
• In chemistry, the term proton refers to the
hydrogen ion, H+.
3) Oxidation phosphorylation –3) Oxidation phosphorylation –
The Proton StoryThe Proton Story
40. •In the mitochondrial matrix electrons from NADH
and FADH are transferred down Electron
Transport Chains (use of coenzymes and
enzymes). As a result the H+ ions ( protons) are
transferred from the matrix into the inter
membrane space through proton pumps.
•H+ build up in the inter membrane space and
create and electrochemical gradient.
•H+ flow back into the matrix through ATP
synthetase. This releases energy which allows
phosphorylation of ADP to ATP in the matrix.
Oxidation phosphorylationOxidation phosphorylation
– The Proton Story– The Proton Story
53. Anaerobic Respiration – Lactic
Acid Fermentation
• When do humans use lactic acid
fermentation?
• Lactic acid is poisonous, what happens
to lactic acid after it has been
produced?
54. When our bodies convert
from aerobic to anaerobic
respiration, we start
making lactic acid.
As soon as this begins, the
body starts building an
oxygen debt.
This is equivalent to the
amount of oxygen it would
have used if aerobic
respiration had continued.
Oxygen Debt - Lactic acid