Ketogenesis Flashcards
What are the names of the ketone bodies produced via ketogenesis?
How is the third ketone body created?
Beta-hydroxybutyrate and acetoacetate are the ketone bodies produced via
ketogenesis.
The third ketone body is acetone which is the breakdown product of acetoacetate.
Why are ketone bodies required in an individual who is obtaining enough energy
from the other macromolecules (carbohydrates, lipid and protein)?
Ketone bodies can be metabolised by the brain as a backup energy source.
This is important as the brain can only derive energy from glucose not lipid.
What metabolic process would acetyl CoA be used for if it could not be processes by the CAC (due to a blockage)?
When acetyl CoA are not being used for the CAC due to a blockage, more of the acetyl CoA are used to make ketone bodies via ketogenesis.
If glucose can not enter the cell (due to a faulty response to insulin) is glucose available inside the cell to be metabolised in glycolysis?
Why/why not?
If glucose is not brought into the cell due to a faulty response to the insulin
hormone then there is no glucose to begin metabolic processes that require
glucose as the input e.g. glycolysis.
Pyruvate (product of glycolysis) can be converted to oxaloacetate which is one of
the reactants needed to begin the CAC. Would an untreated diabetic have oxaloacetate available to begin the CAC?
Why/why not?
As an untreated diabetic can not perform glycolysis due to a lack of glucose
inside the cell, the pyruvate product is not being made.
Without the pyruvate product of glycolysis, there is no pyruvate available to be converted into oxaloacetate.
Why is a lot of acetyl CoA (produced from lipid metabolism) used to produce
ketone bodies in untreated diabetics rather than entering the citric acid cycle (CAC),
as acetyl CoA does in healthy individuals?
Without oxaloacetate available to begin the CAC, there is a build-up of acetyl
CoA that untreated diabetics can not use to produce energy.
Instead the acetyl CoA is used to create ketone bodies via ketogenesis.
What are the health problems associated with having a very large amount of ketone bodies in the blood?
Could this be deadly? Explain
The accumulation of ketone bodies in the blood firstly leads to ketosis and in
more extreme cases ketoacidosis.
Ketone bodies are themselves acidic, so having so many ketone bodies in the blood lowers the pH of the blood. If not corrected quickly ketoacidosis can lead to coma and death.
