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18.6 Respiratory
Substrates
Class Bio
Created @Apr 17, 2021 3:33 PM
Date of Exam @Apr 26, 2021
Exam Questions done?
Reviewed
Teacher Mrs Batchelor
Type Sub-topic
different respiratory substrates
Glucose is not the only organic molecules that is broken down
to release energy for the synthesis of ATP. There are many
other respiratory substrates. Triglycerides are hydrolysed to
fatty acids, which enter the Krebs cycle via acetyl CoA and
glycerol.
18.6 Respiratory Substrates 1
, Glycerol is first converted to pyruvate before undergoing
oxidative decarboxylation, producing an acetyl group which is
picked up by coenzyme A, forming acetyl CoA. The fatty acids
in a triglyceride molecule can lead to the formation of as
many as 50 acetyl CoA molecules, resulting in the synthesis of
up to 500 ATP molecules.
Gram for gram, lipids store and release about twice as much
energy as carbohydrates. Alcohol contains more energy than
carbohydrates but less than lipids. Proteins are roughly
equivalent to carbohydrates.
Proteins first have to be hydrolysed to amino acids and then
the amino acids have to be deaminated (removal of amine
groups) before they enter the respiratory pathway, usually via
pyruvate. These steps require ATP, reducing the net production
of ATP.
The respiratory quotient (RQ) of a substrate is calculated by
dividing the volume of carbon dioxide released by the volume
18.6 Respiratory Substrates 2
18.6 Respiratory
Substrates
Class Bio
Created @Apr 17, 2021 3:33 PM
Date of Exam @Apr 26, 2021
Exam Questions done?
Reviewed
Teacher Mrs Batchelor
Type Sub-topic
different respiratory substrates
Glucose is not the only organic molecules that is broken down
to release energy for the synthesis of ATP. There are many
other respiratory substrates. Triglycerides are hydrolysed to
fatty acids, which enter the Krebs cycle via acetyl CoA and
glycerol.
18.6 Respiratory Substrates 1
, Glycerol is first converted to pyruvate before undergoing
oxidative decarboxylation, producing an acetyl group which is
picked up by coenzyme A, forming acetyl CoA. The fatty acids
in a triglyceride molecule can lead to the formation of as
many as 50 acetyl CoA molecules, resulting in the synthesis of
up to 500 ATP molecules.
Gram for gram, lipids store and release about twice as much
energy as carbohydrates. Alcohol contains more energy than
carbohydrates but less than lipids. Proteins are roughly
equivalent to carbohydrates.
Proteins first have to be hydrolysed to amino acids and then
the amino acids have to be deaminated (removal of amine
groups) before they enter the respiratory pathway, usually via
pyruvate. These steps require ATP, reducing the net production
of ATP.
The respiratory quotient (RQ) of a substrate is calculated by
dividing the volume of carbon dioxide released by the volume
18.6 Respiratory Substrates 2