This is a design quirk that has remained wholly consistent throughout "Star Trek." No ship has a hidden bridge, nor a bridge on its ventral side. The decks on a starship descend from the top.

Lower Decks bring back Star Trek's most historic starships. Former Starfleet Lieutenant D'Vana Tendi (Nol Wells) returned to ...

The Horta were an illustration that there are plenty of life forms in the Star Trek universe that are not remotely humanoid.