It's not there by default, you have to make one. You can copy the bashrc from /etc or make one from scratch. If you do the copy from /etc, be sure to put a period in front of the name to make it invisible.
And for more info, the relevant part of the bash man page:
export -p
The supplied names are marked for automatic export to the envi-
ronment of subsequently executed commands. If the -f option is
given, the names refer to functions. If no names are given, or
if the -p option is supplied, a list of all names that are
exported in this shell is printed. The -n option causes the
export property to be removed from each name. If a variable
name is followed by =word, the value of the variable is set to
word. export returns an exit status of 0 unless an invalid
option is encountered, one of the names is not a valid shell
variable name, or -f is supplied with a name that is not a func-
tion.