Term
| Which organ does gluconeogenesis mainly occur in? |
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Definition
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Term
| How long till glycogen reserves depleted? |
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Definition
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Term
| What mechanism maintains blood glucose levels when glycogen depleted? |
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Definition
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Term
| What metabolic product does gluconeogenesis utilise? |
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Definition
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Term
| How does gluconeogenesis differ from glycolysis? |
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Definition
| Three different steps due to different enzymes/molecules involved |
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Term
| First bypass step (starting with pyruvate) |
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Definition
Pyruvate + CO2 -> Oxaloacetate -> Phosphoenol Pyruvate +CO2
Using ATP and GTP |
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Term
| Origin of pyruvate at start of bypass step 1? |
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Definition
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Term
| How is pyruvate transported out of mitochondrion? (4) |
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Definition
1. Converted to oxaloacetate
2. Oxaloacetate converted to malate
3. Malate transported across mitochondrial matrix
4. Malate converted back into oxaloacetate |
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Term
| What is required to convert oxaloacetate into malate? |
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Definition
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Term
| What is produced when malate is converted back to oxaloacetate? |
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Definition
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Term
| What happens to the CO2 used to convert pyruvate to oxaloacetate? |
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Definition
| It is reformed when oxaloacetate is converted to phosphoenol pyruvate |
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Term
| What enzyme converts pyruvate to oxaloacetate? (think CO2 is added!!) |
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Definition
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Term
| What enzyme converts malate to oxaloacetate (think NAD+ -> NADH) This is also the same enzyme for the reverse reaction |
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Definition
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Term
| Which enzyme removes CO2 from oxaloactate when phosphoenol pyruvate is produced? |
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Definition
| Phosphoenol pyruvate carboxylase |
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Term
| Second bypass step (Fructose 1,6-BP to Fructose 6-P) |
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Definition
| Phosphate is removed from fructose 1,6-BP with the addition of H2O |
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Term
| Why is the second bypass step different to glycolysis? |
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Definition
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Term
| Which enzyme is used in bypass step 2? |
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Definition
| Fructose 1,6-bisphosphatase |
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Term
| Third (and final) bypass step (Glucose 6-P to glucose) |
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Definition
| Phosphate is removed from glucose 6-P with the addition of H2O |
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Term
| Which enzyme is used for bypass step 3? |
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Definition
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Term
| What increases the activity of Fructose1,6-BP in bypass step two? |
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Definition
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Term
| What decreases the activity of fructose1,6-BP in bypass step two? |
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Definition
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Term
| What is the metabolic cost of gluconeogenesis (per glucose produced) |
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Definition
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Term
| Where does the energy come from for gluconeogenesis? |
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Definition
| Fatty acid beta oxidation |
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Term
| What is degraded when no fatty acids are left? |
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Definition
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Term
| Gluconeogenic precursors (3) |
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Definition
1. Amino acid skeletons entering TCA
2. Amino acids converted to pyruvate
3. Lactate can be converted to pyruvate
4. Glycerol |
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Term
| How can glycerol become a glucose precursor? |
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Definition
| Glycerol converted to dihydroxyacetone phosphate (this can be converted to glyceraldehyde 3-phosphate) |
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Term
| Which organ converts lactate to pyruvate? |
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Definition
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Term
| Enzyme required to convert lactate to pyruvate? |
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Definition
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Term
| Form of energy produced when lactate is converted to pyruvate? |
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Definition
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