You're conflating two issues here:

1. Is the usb port recognised

2. Is the card mounted.

The output of

lspci

should give you a good idea of the first.

To mount the card you probably need to edit /etc/fstab

you'll probably find a line like:

/dev/sda1 /mnt/sda1 vfat noauto,users,exec,umask=000 0 0

with a # in front of it.

As root, edit the line to remove the #

then (still root) do

mount -a

You may need to add yourself to the usb group, too (use kuser), and do make sure that /mnt/sda1 actually exists.