Energy bands and semiconductors

Just thinking about the band structures we learnt with the Bloch model.
Bands determine the state, so insulator, metal, semimetal, semiconductor by the filling (or not filling) of electrons or holes.

We saw the band structures again in Paul's last set of lectures on semiconductors.

We were introduced to the donor and acceptor bands, also the valance and conduction bands.

How are these bands related to the energy bands from the Bloch picture?
Are they the same thing?


Also, I still don't quite understand the distinction between the valance/conduction bands and the donor/acceptor bands?
 I take it that the donaor accept are within the conduction/valance pair, but why are there two pairs of them?


Final set of questions, when we consider these two sets of bands, their expressions (p592-3 A&M) no longer contain the Fermi energy. Are they related to the Fermi energy, else where has the Fermi gone?

Apologies for all the questions.
Thanks.