Pack 17 - Respiration Flashcards
What is the equation for aerobic respiration?
C6H12O6 + 6O2 —> 6CO2 + 6H2O + (e- + 36ATP)
Glucose + Oxygen —> Carbon Dioxide + Water ( + energy)
What are the three stages of aerobic respirtation and where do they take place?
glycolysis - Cytoplasm
link reaction and krebs cycle - mitochondria
Oxidative phosphorylation - mitochondria
Describe glycolysis
glucose (6C) is phosphorylated to glucose phosphate (6C)
During this process 2 ATP goes to 2 ADP
glucose phosphate (6C) then goes to 2 triose phosphate (3C)
2 triose phosphate (3C) then goes to 2 pyruvate (3C)
4 ADP + 2 pi is oxidised to 4 ATP and 2 NAD is oxidised to 2 NADH
Net gain of 2 ATP and 2 NADH
This is substrate level phosphorylation
Describe the Link Reaction
Pyruvate (3C) from glycolysis is decarboxylated into Acetate (2C)
In this time NAD is reduced to form NADH
Acetate (2C) combines with Coenzyme A to form Acetylcoenzyme A (2C)
For every glucose molecule this reaction occurs twice
Describe the Krebs Cycle
Acetylcoenzyme A (2C) joins the Krebs Cycle from the Link reaction
Binds with a 4C molecule to create a 6C molecule
Coenzyme A is then released to be used in the Link reaction
The 6C molecule undergoes decarboxylation and becomes a 5C molecule
Through a series of oxidation reactions the 5C molecule loses hydrogens to produce a 4C molecule again.
Describe Oxidative Phosphorylation
Reduced coenzyme releases its hydrogen, which becomes a proton and electron.
Coenzyme returns to matrix to pick up more hydrogen
The electron is passed along the electron transport chain in the inner mitochondrial
membrane, releasing energy as it goes.
The energy is used to pump protons into intermembrane space
Protons pass back into the matrix through ATP synthase enzyme
Energy used to combine ADP and Pi to make ATP
Oxygen acts as the terminal electron acceptor in the electron transport chain,
combining with the electron and proton to make water
How does anaerobic respiration occur?
No oxygen so glycolysis the only place ATP can be created
How does glycolysis continue without oxygen?
pyruvate must be removed
NADH produced must be oxidised and recycled so that it is available to further hydrogen
How do animals go about anaerobic respiration?
convert pyruvate to lactate
reaction uses NAD/NADH, oxidising it to NAD again so it is available for glycolysis
How do plants and yeast cells go about anaerobic respiration?
convert pyruvate to ethanol and carbon dioxide
result is similar to animals as pyruvate is removed and NAD regenerated
What is the respiratory quotient of glucose?
Glucose = 1.0
What is the respiratory quotient of Triglycerides?
Triglycerides = 0.7
What is the respiratory quotient of Protein?
Protein = 0.9
How do you calculate Respiratory Quotient (RQ)?
RQ= vol of CO2 produced/volume of O2 used
