The bare LED can be driven from the Morsel and Ditto without having to worry about the electrical characteristics or connecting any other parts.
A Coupler may also be used to attach wires to the LED without having to solder.
To light up a bare LED without a Morsel or Ditto, the LED needs between 2v-3v, and a current of up to 20mA. So 2 AA batteries in series (which is 3v) with a resistor will light the LED, or 1 CR2032 watch battery (which is 3v) with a resistor.