It was shown before that the effect of the combined magnetic field on the gravitropic reaction of plants’ roots depended essentially on the initial orientation of roots and combined magnetic field and gravity vectors. Goal of the work fulfilled under the conditions of lowed level of magnetic and electric fields’ noises, was, to summary the experimental results obtained in this and our previous works and to understand the common mechanism of these differences. So the experiments of simultaneous action of static magnetic field and alternating electric field of different orientations relatively each other were observed. The gravitropic reaction of cress roots was investigated in static vertical magnetic field and alternating electric field of all possible different directions relatively the magnetic field and roots direction (3 variants). The alternating electric field was tuned to cyclotron frequency of Ca2+ ions in vertical magnetic field. The biological effect wasn’t observed at all for the roots parallel to static magnetic field. The analogous investigation has been fulfilled for horizontal magnetic field. The alternating electric field was tuned to cyclotron frequency of Ca2+ ions in horizontal magnetic field. Six different types of relative directions of magnetic field, electric field and roots were investigated. The clear biological effect was obtained only for two cases from six, when the roots were not parallel to the magnetic field. The direction of roots relatively both static magnetic field and alternating electric field is very important. The effect may be explained by membrane breathing caused by alternating electric field because the alternating electric field created the alternating magnetic field. But other explanation is the phase transition in near membrane water and it is more likely. The effect caused by the rotation of ions around the domains in the vacuum layer. This explanation explained very well the results obtained both in combined magnetic field and in the static magnetic field combined with the alternating electric field.