  We investigate the phase diagram of the so-called
Polyakov--Nambu--Jona-Lasinio model at finite temperature and non-zero chemical
potential with three quark flavors. Chiral and deconfinement phase transitions
are discussed and the relevant order-like parameters are analyzed. The results
are compared with simple thermodynamic expectations and lattice data. We
present the phase diagram in the ($T,\,\mu_B)$ plane, paying special attention
to the critical end point: as the strength of the flavor-mixing interaction
becomes weaker, the critical end point moves to low temperatures and can even
disappear.
