  We investigate the morphology and temporal variability of a quiet Sun network
region in different solar layers. The emission in several EUV spectral lines
through both raster and slot time series, recorded by EIS/Hinode is studied
along with H$\alpha$ observations and high resolution spectropolarimetric
observations of the photospheric magnetic field. The photospheric magnetic
field is extrapolated up to the corona showing a multitude of large and small
scale structures. We show for the first time that the smallest magnetic
structures both at the network and the internetwork contribute significantly to
the emission in EUV lines, with temperatures ranging from 8 10$^{4}$ K to 6
10$^{5}$ K. Two components of transition region emission are present, one
associated with small-scale loops that do not reach coronal temperatures and
another one acting as an interface between coronal and chromospheric plasma.
Both components are associated with persistent chromospheric structures. The
temporal variability of the EUV intensity at the network region is also
associated with chromospheric motions, pointing to a connection between
transition region and chromospheric features. Intensity enhancements in the EUV
transition region lines are preferentially produced by H$\alpha$ upflows.
Examination of two individual chromospheric jets shows that their evolution is
associated with intensity variations in transition region and coronal
temperatures.
