Standard Module vs. Camera Module (DIMM-MX257)

What is the difference between the standard module DIMM-MX257 and the camera module DIMM-MX257 CAM?

The camera module DIMM-MX257 CAM supports a camera/video in the interface. But the 2nd SD Card, UART_D and GPIO_A to GPIO_D are not available on the DIMM-MX257 CAM module.