respiration Flashcards
What are the four stages in aerobic respiration
Glycolysis
Link reaction
Krebs cycle
Oxidative phosphorylation
Describe what happens in Glycolysis
Splitting one molecule of glucose into two smaller molecules of pyruvate
happens in cytoplasm
doesn’t need oxygen as it is aerobic
Outline the process of glycolysis
Glucose is phosphorylated (2 phosphates are added to form 2 molecules of ATP)
1 molecule of hexose bisphosphate is created and 2 molecules of ADP are created
TP is oxidised
this forms 2 pyruvate
NAD collects Hydrogen ions forming 2 reduced NAD
4 ATP are produced but 2 were used up so net gain of 2
What happens in the link reaction
pyruvate is decarboxylated
NAD is reduced to NADH-collects hydrogen from pyruvate to form acetate
acetate combined with coenzyme A forms acetyl CoA
what happens in the krebs cycle
acetyl group from acetyl CoA combines with oxaloacetate to form citrate
CoA goes back to link reaction
Citrate molecule (6C) is converted into 5C molecule
decarboxylation and dehydrogenation occurs
hydrogen is used to produce reduced NAD
5C converted into 4C molecule
decarboxylation and dehydrogenation occur
1 reduced FAD and 2 reduced NAD is formed
what happens in oxidative phosphorylation
h atoms released from reduced nad and fad
electrons and protons released
electrons move along etc losing energy at each of the three carriers
energy used to pump protons from mitochondrial matrix into intermembrane space
electrochemical gradient is formed
protons move down electrochemical gradient via ATP synthase and ATP is synthesised
What are the two types of anaerobic respiration
alcoholic fermentation
lactate fermentation
where does lactate fermentation occur
Mammals
What happens in lactate fermentation
reduced NAD from glycolysis transfers hydrogen to pyruvate to form lactate
What happens in alcoholic fermentation
CO2 is removed from pyruvate to form ethanal
reduced NAD from glycolysis transfers hydrogen to ethanal to form ethanol and NAD
