I have a short answer question, pleae help!

When your blood calcium level drops too low, the drop is detected by extracellular calcium receptor cells, which signal the parathyroid gland. The parathyroid gland then releases parathyroid hormone (PTH), which in turn promotes calcium reabsorption by the kidneys. Thus less calcium is excreted in the urine, and the blood calcium level returns to normal.

 

Identify the elements of a feedback loop in this scenario.

 

Is this a positive or a negative feedback loop?
Explain your answer.

 

 

Thanks!
asked Aug 24, 2012 by anonymous

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1 Answer

Here is a graphic that shows the process.  This shows some additional effects of PTH that you didn't mention. This is a negative feedback loop.  The production of one product is involved in the regulation of others.  This will generally remain stable over time. 

                                                                    

answered Aug 27, 2012 by anonymous
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