Is there any junction, or branch element for jumper cables?
First, let's be clear that "jumper cables" refers to little wires used to connect things on a breadboard, not to connect two car batteries together.

The usual answer is that the breadboard provides the multiple connections to a net.  The common solderless breadboards with lots of little sockets have 5 sockets wired together in a strip.  The provides enough sockets to connect multiple strips together using only single point to point jumper wires.  Technically only 3 sockets per strip are necessary for this to work and still allow components to be connected beyond the jumper wires, but 5 per strip gives you more flexibility and makes it easier to connect multiple components directly.