Ornithine Cycle: Ornithine Cycle:
Excess amino acids in the liver
undergo deamination.
This produces keto acids (that
can be used in respiration) &
ammonia.
Ammonia is carboxylated (+ CO2)
& undergoes a condensation
reaction (- H2O) to produce
Citrulline.
Citrulline reacts with ammonia
(+ NH3) & undergoes a
condensation reaction (- H2O) to
produce arginine.
Arginine is hydrolysed (- H2O) to
produce orthenine (an amino
acid not used in proteins) &
urea.
Urea is an excretory product that
will be removed by the kidneys.
Excess amino acids in the liver
undergo deamination.
This produces keto acids (that
can be used in respiration) &
ammonia.
Ammonia is carboxylated (+ CO2)
& undergoes a condensation
reaction (- H2O) to produce
Citrulline.
Citrulline reacts with ammonia
(+ NH3) & undergoes a
condensation reaction (- H2O) to
produce arginine.
Arginine is hydrolysed (- H2O) to
produce orthenine (an amino
acid not used in proteins) &
urea.
Urea is an excretory product that
will be removed by the kidneys.
