The ulna is in the forearm.
Of the two forearm bones, the ulna is the major contributor to the elbow joint, giving you flexibility there, as opposed to the radius, which is the main contributor to the wrist. In four-legged...
They are both unusally strong for their size, and they have similar muscle style.
At the wrist. Note: It is more commonly known as the Radial Pulse. :-)
No they have fins; caudle,pectorals,dorsal,anal, and ventral.