The gate remains in such a state for on average 54 s (Table 1) and
then tube x restores its conductivity. The flow of cytoplasm is then
directed through tubes x and y, and tube z becomes unused,
shrinks due to elasticity and its diameter returns to a resting value
30 ym. This is somewhat analogous to an automated adjustment
employed in a microfluidic implementation of a Wheatstone
bridge [35]. The state of the gate after mechanical stimulation
of tube y (Fig. 2e) is shown in Figs. 2f and 3c. The gate is restored to
its original state in less than a minute after mechanical stimulation.
When the flow stops in x and y at the same time the flow may
not occur in tube z because the tube becomes isolated from the
upper part of protoplasmic network. Therefore we assume that
z = 0 if x = 0 and y = 0. Thus an XOR gate is implemented z = x y
(Fig. 3a–d).