8.2: Cell respiration
Teaching time allocated: 5 hours
Practical time allocated: 0 hours
key vocab
Prior Learning & retrieval practice
Review 2.8 Cell Respiration
Review 8.1 Metabolism
Review 2.5 Enzymes
Review 2.4 Proteins
Essential idea: Energy is converted to a usable form in cell respiration.
Watch these videos to review the topic.
Questions to consider:
In cell respiration what is the usable form that energy is converted into?
What is it converted from?
Where did this energy originate?
redox reactions
U1: Cell respiration involves the oxidation and reduction of electron carriers.
Exercise 1: Read the relevant chapter of your textbook and connect extend challenge. Then answer the following questions:
What are redox reactions?
What is oxidation?
What is reduction?
What is an electron carrier in cell respiration?
When are they reduced?
What becomes oxidised when they are reduced?
When are they oxidised?
What becomes reduced when they are oxidised?
glycolysis
U2: Phosphorylation of molecules makes them less stable.
U3: In glycolysis, glucose is converted to pyruvate in the cytoplasm.
U4: Glycolysis gives a small net gain of ATP without the use of oxygen.
Guidance:
The names of the intermediate compounds in glycolysis and the Krebs cycle are not required.
Exercise 2: Watch this video and connect extend challenge.
Exercise 3: Create a flow chart of glycolysis. Note the guidance from the biology guide.
Exercise 4: Answer these questions:
Why does phosphorylation of molecules make them less stable?
How is this utilized in glycolysis?
Is glycolysis an aerobic or anaerobic process?
Why?
How much ATP is produced by glycolysis (gross)?
How much ATP is produced by glycolysis (net)?
What proportion of ATP produced in the total aerobic pathway is this?
the mitochondria
S2: Annotation of a diagram of a mitochondrion to indicate the adaptations to its function.
Exercise 5: Complete the Quizlet "learn" for the below deck
U12: The structure of the mitochondrion is adapted to the function it performs.
Exercise 6: Copy and complete this table:
Electron tomography
A1: Electron tomography used to produce images of active mitochondria.
Exercise 7: What is Electron tomography and how is it used to produce images of active mitochondria?
krebs cycle
U5: In aerobic cell respiration pyruvate is decarboxylated and oxidized, and converted into acetyl compound and attached to coenzyme A to form acetyl coenzyme A in the link reaction.
U6: In the Krebs cycle, the oxidation of acetyl groups is coupled to the reduction of hydrogen carriers, liberating carbon dioxide.
Guidance:
The names of the intermediate compounds in glycolysis and the Krebs cycle are not required.
Exercise 8: Create a flowchart of the Krebs cycle and link reaction
S1: Analysis of diagrams of the pathways of aerobic respiration to deduce where decarboxylation and oxidation reactions occur.
Exercise 9: Label your flow chart to show where decarboxylation and oxidation reactions occur.
electron transport chain
U7: Energy released by oxidation reactions is carried to the cristae of the mitochondria by reduced NAD and FAD.
Exercise 10: Copy and complete this table
U8: Transfer of electrons between carriers in the electron transport chain in the membrane of the cristae is coupled to proton pumping.
U9: Oxygen is the final electron acceptor.
U10: In chemiosmosis protons diffuse through ATP synthase to generate ATP.
U11: Oxygen is needed to bind with the free protons to maintain the hydrogen gradient, resulting in the formation of water.
Exercise 11: Explain how the electron transport chain results in the production of ATP by using energy released by electron carriers.
PETER mitchels chemiosmotic theory
NoS: Paradigm shift—the chemiosmotic theory led to a paradigm shift in the field of bioenergetics. (2.3)
