Locating User Defined Attribute Definitions in Oracle Transportation Manager

Many tables in OTM have user defined attributes (UDAs) which just have names like Attribute1, etc.  I work in the data warehouse group and we try to find meaningful names and definitions for these UDAs.  Unfortunately, many times our business partners are new to the product and do not know how these attributes are defined or know where the information can be found.

First, is it required that these UDAs be given actual business names and definitions?

Second, is there a single table where these definitions can be found for a given application like OTM or does each table have its own definition table?