Questions
Jacob and his mates went to an all-you-can-eat seafood buffet. About a month later he starts to feel unwell. He develops a fever, he is nauseous, starts vomiting and has diarrhoea. This continues for several days and he is starting to feel quite weak. He also notices that he doesn’t have to urinate very often but when he does it is only a small amount of dark yellow urine.
1. The hormone responsible for maintaining water balance homeostasis is anti-diuretic hormone (ADH). Complete the following table outlining the feedback mechanism for ADH.
Stimulus
Receptor
Site of production
Site of release
Effector
Mechanisms of hormone action
Impact on urine output
2. What type of feedback loop is this and explain your reasoning?
3. Using an example from the endocrine system explain the other type of feedback loop.
After a week he has an appointment with his doctor. The doctor notices that his sclera (whites of his eyes) are yellow and doctor suspects that he jaundice possibly as a result of a hepatitis virus – but is not sure which type. He immediately sends Jacob for a blood and urine test to confirm. By the time Jacob makes it for his tests his urine has become a dark amber colour and his skin is turning yellow. The results of his test confirm the diagnosis of Hepatitis A. In addition, it was noted that his urine has high levels of potassium
4. Outline the three processes of urine formation.
5. Using your knowledge of the hormones involved in the urinary discuss what might have caused the high levels of potassium in Jacob’s urine. The source of hepatitis A virus was determined to be the seafood from the buffet.
6. Describe the pathophysiology of diarrhea and explain how it causes Jacob’s dehydration, lethargy and weakness
