Originally posted by renorenal:
[b]NEW
MYSTERY
I am the heart
Yes, this is an obvious clue
To help you narrow things down
I have 4 prominent valves
If you'd noticed
I have 3 more on my right
And 2 more on the left
To allow blood coming in
And out of the heart
But there is particularly one
Smack dab right in the middle
Can you make a guess
Of what I am? 
[/b]
Tricuspid valve on the right, biscuspid valve on the left
Middle is the median septum
