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Regulation (Homeostasis)

Co +NH 3 Citrulline Aspartate
2
2ATP
Pi + AMP ATP
H O
Carbamoyl Pi 2
phosphate
AMP + Pi
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Ornithine Argininosuccinate

Urea

H O Arginine
2
Fumarate

Figure 7.9: The Ornithine cycle

7.3.4 Urinary disorders in human and severe itching from the imbalance of
The urinary tract consists of the kidneys, minerals in the body.
ureters, bladder and urethra. Urinary
disorders include any infections or Renal failure (RF) or kidney failure
conditions that affect any of these parts Renal failure is a decrease or cessation
of the urinary system or their functions. of glomerular filtration in humans (it
The following are some of the common is a partial or complete loss of kidney
urinary disorders in human beings: function). Kidney failure can be either
acute or chronic. In acute renal failure
Uremia (ARF), both kidneys abruptly stop

This condition results from toxic effects working. The main feature of ARF is
of abnormally high concentrations of urea either oligouria (scanty urine production)
in the blood resulting into kidneys’ failure in which the daily urine output is less
to expel it via urine. The end products than 250 ml or anuria in which daily urine
of protein metabolism accumulate in output is less than 50 ml. The causes of
the blood but they are normally filtered renal failure may be low blood volume
out when the blood passes through (atherosclerosis), decreased cardiac
kidneys. However, urea accumulation output, damaged renal tubules, kidney
in the blood is comparatively high in stones, nephritis, and some excessive use
uremia victims. In such patients, urea of antibiotics. The effect of renal failure
can be removed by the process called includes oedema, that is accumulation
haemodialysis. However, there are still of excess fluids in various parts of the
some complications that affect people on body, which results into swelling of legs.
dialysis such as cardiovascular problems Also, the potassium level rises, leading to

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