Translation of "internal clock" into Spanish

I'm just beginning to realize how much of the body is held together by its own internal clock.

Estoy descubriendo en nuestro funcionamiento cuánto influye el reloj biológico interno.

They appear to have internal clocks to compensate for the movement of these heavenly bodies.

Parece que tienen relojes internos que compensan por el movimiento de estos cuerpos celestes.