Download Redox reaction during glycolysis

CELLULAR RESPIRATION
TOPIC 3.7 (core) and TOPIC 8.1 (HL)
Topic 3.7 Cellular respiration
Objectives
• Define cell respiration.
• State that, in cell respiration, glucose in the cytoplasm is
broken down by glycolysis into pyruvate, with a small
yield of ATP.
• Explain that, during anaerobic cell respiration, pyruvate
can be converted in the cytoplasm into lactate, or ethanol
and carbon dioxide, with no further yield of ATP.
• Explain that, during aerobic cell respiration, pyruvate can
be broken down in the mitochondrion into carbon dioxide
and water with a large yield of ATP.
• Which form of energy is used by living
things?
Living things use chemical energy for their
biological work.
• What is the main source of energy for the
Earth?
SUN
• How do living things get this energy?
What are the biological works
which require energy?
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Synthesis of new biomolecules
Active transport
Cell division
Movement
• Energy can be converted from one form to
another, but it is neither created nor
destroyed.
• SUN
plants
ATP
photosynthesis
organic molecules
cellular activities
* All cells use ATP for their cellular activities.
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Organic molecules have chemical energy.
1gr carbohydrate
4.2 kcal
1gr protein
4.3 kcal
1gr lipid
9.3 kcal
• Why do lipids store more energy than
other organic molecules?
Structure of ATP
ATP PRODUCTION
1- Substrate level phosphorylation:
is the production of ATP by the direct
transfer and donation of phosphoryll
group to ADP from a phosphorylated
substrate.
2- Oxidaditive phoshorylation:
production of ATP by redox reaction in
the presence of oxygen
3- Photophosphorylation: production
of ATP by light energy.
4- Chemophosphorylation:
production of ATP by oxidation of
inorganic substances such as NO3, Fe2+
GENERAL FORMULA OF CELLULAR
RESPIRATION
glycolysis
Glucose
Pyruvic acid
Aerobic respiration
in mitochondria
fermentation
Ethanol
İn yeast
Lactic acid
in muscle cell
GLYCOLYSIS
• Series of reactions which are common in aerobic
reactions and anaerobic reactions. (all living
cells do glycolytic reactions)
• Take place in cytoplasm.
• During glycolysis 2 ATP are used and 4 ATP, 2
NADH2 (coenzyme), 2 H2O and 2 pyruvic acids
are produced.
• ATP are produced by substrate level
phosphorylation.
• At the end of the glycolysis 2 ATP are gained.
CITRIC ACID (KREBS) CYCLE
ELECTRON TRANSPORT
CHAIN
• ETS is a
group of
protein that
transfer
electrons.
• Most of the
ATPs are
produced by
oxidative
phoshorylation
in the ETS.
LACTIC ACID FERMENTATION
ETHYL ALCOHOL FERMENTATION
HL TOPIC 8.1:Cell respiration
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State that oxidation involves the loss of electrons from an element, whereas reduction
involves a gain of electrons; and that oxidation frequently involves gaining oxygen or
losing hydrogen, whereas reduction frequently involves losing oxygen or gaining
hydrogen.
Outline the process of glycolysis, including phosphorylation, lysis, oxidation and ATP
formation.
Draw and label a diagram showing the structure of a mitochondrion as seen in
electron micrographs.
Explain aerobic respiration, including the link reaction, the Krebs cycle, the role of
NADH + H+, the electron transport chain and the role of oxygen.
Explain oxidative phosphorylation in terms of chemiosmosis.
Explain the relationship between the structure of the mitochondrion and its function.
• Cellular respiration is an oxidation
reduction (redox) rection.
HL-8.1.1
REDOX REACTIONS IN
CELLULAR RESPİRATİON
* In the living things oxidation means; H
atoms leave organic molecules. At the
same time H atoms take energy and
electrons from the chemical bond between
H and C atom of the organic compound.
*These H atoms bind with coenzymes (NAD
and FAD). That means e and energy are
transferred to coenzymes.
*NAD and FAD transfer e, H and energy to
ETS which are used for oxidative
phosphorylation.
• In the areobic and anaerobic reactions organic
molecules (glucose) are oxidized (give
electrons).
• Which molecules are reduced?
*In arebic respiration during glycolysis and Krebs
cycle e are taken from glucose and transferred
in the ETS. The last e acceptor is oxygen.
*In fermentation last e acceptor is pyruvic acid and
acetaldehyde.
Redox reaction during glycolysis
Glucose
2 ATP
3C molec
3C molec
2H
2H
2 ATP
2 ATP
pyruvate
pyruvate
2H
2H
Acetyle Co-A
Acetyl-Co A
Krebs cycle
2H
Krebs cycle
2H
2H
2H
2H
2H
2H
2H
ETS
Electron transport system (ETS)
• Chemiosmosis
Chemiosmosis
• NADH+H+ supplies pair of H atoms to the first carrier in the chain,
with the NAD+ returning to the matrix.
• The hydrogen atoms are split, to release two electrons, which pass
from carrier in the chain.
• Energy is released as the e- pass from carrier to carrier, and three of
these use this energy to transfer protons (H+ ) across the inner
membrane space.
• As electrons continue to flow along the chain and more and more
protons are pumped across the inner mitochondrial space, a
concentration of protons builds up. The proton gradient is the store
for potential energy.
• To allow e- to continue to flow, they must be transferred to a terminal
e acceptor at the end of the chain. In aerobic respiration it is Oxygen
(02 ). When combines with hydrogen it forms water.
• Protons pass back to matrix through ATP synthase. As they move
down the concentration gradient, energy is released and this energy
is used to make ATP.