3. Within a few days after a fast begins, nitrogen excretion accelerates to a relatively high level. After a few weeks, the rate of urea excretion falls to a lower level. The excretion of nitrogen then continues at a relatively constant rate until the body is depleted of triacylglycerol stores when the rate of urea and ammonia excretion again rises to a very high level. a. Describe the events that trigger and the purpose of the initial surge of nitrogen excretion? Include the hormones and metabolic pathways that are involved. b. Why does the nitrogen excretion rate decrease after several weeks of starvation? c. Explain the increase in nitrogen excretion that occurs when lipid stores are depleted?
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After a few weeks, the rate of urea excretion falls to a lower level. The excretion of nitrogen then continues at a relatively constant rate until the body is depleted of triacylglycerol stores when the rate of urea and ammonia excretion again rises to a very high Show more…
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Sri K.
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