Urinary System Video & Assignment

We have a circulatory system quiz (celebration of learning) on Wednesday - okay fine.  Friday.  Today we are starting to learn about the Urinary system - here is a good 6 minute intro video identifying the main structures and how the urinary system functions to excrete wastes and maintain water balance:

After watching this video - please find an interesting question that you have about the urinary system, excretion or the kidneys to blog about.  Then, LEARN ABOUT IT! Post the question, the answer, at least one picture and/or video and links to the best websites that you used for your research (as live links using the link feature).
If you get this done before class is over, please follow someone else's blog & read their question and answer (ie. learn something else interesting) and write a comment for them.