Just as a matter of fact, ethernet doesn't always use TCP/IP because there isn't really a "TCP/IP" protocol. Those are two different protocols for two different layers of the software interface. In all likelihood, it's using TCP/FTP.
You have a gross misunderstanding. There is indeed a TCP/IP protocol. It's transmission control protocol over internet protocol. UDP/IP is also a protocol. Ethernet isn't any one protocol. It's made up of many moving parts and the abstraction it provides up/down stream layers is why it's so robust, reliable, and elegant.
There is no such thing as TCP/FTP because FTP doesn't live at layer 3. It's layer 7 (application).