2. Note!
Please see 3.7 Cell Respiration Core prior to using this presentation.

3. Assessment Statements
8.1.1 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.
8.1.2 Outline the process of glycolysis, including phosphorylation, lysis, oxidation and ATP formation.
8.1.3 Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs.
8.1.4 Explain aerobic respiration, including the link reaction, the Krebs cycle, the role of NADH + H+, the electron transport chain and the role of oxygen.
8.1.5 Explain oxidative phosphorylation in terms of chemiosmosis.
8.1.6 Explain the relationship between the structure of the mitochondrion and its function.

4. 8.1.1
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.

5. O I L R G
Oxidation Is
Loss
Reduction
Gain

6. Loss and gain of what? hydrogen electrons oxygen + e- O O + O2 H + H+
Oxidation
Reduction
+ e- X X+ X+
+ e- X X X X X
+ O2 O O
+ O2 X H X
+ H+ X
+ H+ X H

7. Respiration involves oxidation and reduction.
An organic compound (glucose) is oxidised
while ADP is reduced to ATP
In cell processes biochemical processes
are coupled to the oxidation of ATP to ADP

8. 8.1.2
Outline the process of glycolysis, including phosphorylation, lysis, oxidation and ATP formation.

9. Aerobic respiration, gives a higher yield of ATP.
ADP + Pi
ATP
Aerobic respiration
glycolysis
link reaction
Kreb’s cycle
electron transport chain
oxidative phosphorylation

10. Glycolysis (sugar splitting)
phosphorylation
ATP C C C C C C
ADP + Pi
Glucose 6C P C C C C C C P
lysis P C C C C C
NAD+ C P
NADH+ + H+
oxidation C C C
CYTOPLASM C C C
2 x 3C pyruvate

11. Phosphorylation 2 ADP + Pi 2 ATP
There is an
increase in
energy
Phosphorylation uses 2 ATP to add 2 phosphate groups to glucose.
This makes the glucose molecule more unstable so it becomes easier to break bonds.
The phosphate groups also allow the hexose bisphosphate to bind more effectively with its enzyme.
Energy
2 ADP + Pi
2 ATP
Time

12. Lysis hexose diphosphate triose phosphate
Triose phosphate or TP is an intermediate in many biochemical reactions.
The phosphate groups help the TP to bind to its enzyme.

13. Oxidation (ATP formation)
There are 2 TP molecules made from each glucose.
A total of 4 ATP molecules are made.
But, we used 2 during phosphorylation.
So, we have a net production of 2 ATP
NAD+
2 ADP + Pi
reduction
oxidation
2 ATP
NADH+ + H+

14. What is NAD+?

15. Watch the video and then summarise of the key points of glycolysis

16. Summary Takes place in the _________ No _________ needed
6C ________ is converted into 3C _________
__ ATP made and __ ATP used
cytoplasm
oxygen
glucose
pyruvate 4 2
Net gain
2 ATP
2 NADH+ + 2H+
2 3C pyruvate

17. 8.1.3
Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs.
8.1.6
Explain the relationship between the structure of the mitochondrion and its function.

18. Mitochondria

19. Site of aerobic respiration
Pyruvate is further oxidised to release more ATP.
Only found in eukaryotic cells.
Cells that need a lot of energy will have many mitochondria ( liver cell) or can develop them under training (muscles cells).

20. Features of mitochondria
Surrounded by a double membrane.
Inner membrane folded to form 'cristae'. LSA for ATP production.
Space between the two membranes which is narrow creating a place to concentrate H+

21. The inner space is called the matrix.
It contains the enzymes needed for respiration.especially those of the Kreb’s cycle.
An example of compartmentalisation (isolation of substances needed for a particular function)
Mitochondria also contain some of their own DNA (mDNA) html

22. PPQ Review
(a) Draw a labelled diagram showing the structure of a mitochondrion as seen in an electron micrograph (4)
(b) Explain the relationship between the structure of the mitochondrion and its function (3)

23. (a) Award marks for any of the following clearly drawn and correctly labelled.
cristae;
inner membrane;
outer membrane;
intermembrane space;
matrix;
ribosomes;
DNA; max
(b) cristae provide surface area for oxidative phosphorylation;
inner membrane contains electron transport chains/ATP synthase (which
carry out oxidative phosphorylation);
outer membrane separates the mitochondrion from the rest of the cell;
mitochondrial DNA/ribosomes make (mitochondrial) proteins;
small volume intermembrane space allows for higher concentration
of protons;
matrix has enzymes for the Krebs cycle; max

24. 8.1.4
Explain aerobic respiration, including the link reaction, the Krebs cycle, the role of NADH + H+, the electron transport chain and the role of oxygen.

25. Link Reaction Decarboxylation - removal of carbon from the pyruvate
CoA
NAD+
Carbon forms carbon dioxide C
NADH + H+
CO2
2C Acetyl group binds temporarily with Coenzyme A
CoA C C
Acetyl CoA

26. Kreb’s Cycle citric acid NADH + H+ FADH2 ATP FAD NAD+ ADP + Pi NAD+
CO2
NADH + H+
NADH + H+ C C C C C
NAD+ C
CO2

27. This is a metabolic cycle.
Each step requires enzymes to reduce the activation energy.
The reactions take place in the mitochondrial matrix.
This reaction occurs within the matrix where each intermediate becomes the substrate for the next step.

28. Watch this:

29. 8.1.5
Explain oxidative phosphorylation in terms of chemiosmosis.

31. Watch these:

32. Task
Reorder the sentences in the booklet to explain the process of chemiosmosis
(answers on the next page)

33. The inner membrane is folded into cristae and
embedded in this membrane are proteins
which form an electron transport chain
Reduced NAD+ and FAD are oxidised releasing electrons and H+ ions.
The electrons are passed along the chain while the
H+ are pumped by the membrane proteins into the inner membrane space.
These H+ ions accumulate and their concentration increases.
When they diffuse back to the matrix they pass through
a membrane protein called ATP synthase.
The flow of electrons through ATP synthase
drives an enzyme reaction which converts ADP + Pi to ATP.

34. ATP synthase is an enzyme embedded in the cristae membrane.
H+create an electrochemical gradient (chemical potential energy).
The H+pass through a channel in the enzyme driving the motor.
The motor spins bringing together ADP and Pi to produce ATP

35. NADH + H+, FADH2, O2
ATP, H2O, NAD+, FAD