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We present an analysis of spectrophotometric observations of the latest cycleof activity of the symbiotic binary Z And from 2006 to 2010. We estimate thetemperature of the hot component of Z And to be \approx 150000 - 170000 K atminimum brightness, decreasing to \approx 90000 K at the brightness maximum.Our estimate of the electron density in the gaseous nebula isN_{e}=10^{10}-10^{12} cm^{-3} in the region of formation of lines of neutralhelium and 10^6-10^7 cm^{-3} in the region of formation of the [OIII] and[NeIII] nebular lines. A trend for the gas density derived from helium lines toincrease and the gas density derived from [OIII] and [NeIII] lines tosimultaneously decrease with increasing brightness of the system was observed.Our estimates show that the ratios of the theoretical and observed fluxes inthe [OIII] and [NeIII] lines agree best when the O/Ne ratio is similar to itsvalue for planetary nebulae. The model spectral energy distribution showedthat, in addition to a cool component and gaseous nebula, a relatively coolpseudophotosphere (5250-11 500 K) is present in the system. The simultaneouspresence of a relatively cool pseudophotosphere and high-ionization spectrallines is probably related to a disk-like structure of the pseudophotosphere.The pseudophotosphere formed very rapidly, over several weeks, during a periodof increasing brightness of Z And. We infer that in 2009, as in 2006, theactivity of the system was accompanied by a collimated bipolar ejection ofmatter. In contrast to the situation in 2006, the jets were detected evenbefore the system reached its maximum brightness. Moreover, components withvelocities close to 1200 km/s disappeared at the maximum, while those withvelocities close to 1800 km/s appeared.

Formation of a disk-structure and jets in the symbiotic prototype Z And during its 2006-2010 active phase