God help GUEST! Here is the answer to your question--Yes.

As is more or less pointed out above, the dominant chord (V7--G7 in C, etc) is really a diminished chord-- B D F --based on the leading tone,( which is a half step below the fundamental) that holds on to the fifth step of the tonic chord.

I mention this only because it allows me to introduce my "slinky" chord theory--which is that you think of the scale as a slinky which you either scrunch up or stretch to make chords---Start with the tonic, C E G--stretch it down a half step with the top end anchored down and you get the
dominant--B D F   G--keep the top anchored scrunch it up, and you get C#dim--C# E G--slide the whole thing up, and you get Dm--D F A--keep the bottom fixed and scrunch down for a Cdim--