1. Bacteria have internal and external sensors of different types.
2. Bacteria can synthesize sensors and effectors when required and eliminate them when no longer needed (a solution in response to changes of the environment less frequently found in higher organisms). [N.B. "Effector" is defined by A Dictionary of Science (1999) as "a cell or organ that produces a physiological response when stimulated by a nerve impulse" - V.T.]
3. Bacteria have been able to move for about 3 billion years now by means of rotating effectors (flagella) that act like a ship's screw...
4. Bacteria react to stimuli in indirect ways and the coupling between stimuli and responses is modifiable.
5. Bacteria identify and compare stimuli at different times (a process based on sensory stimulation and a simple memory).
6. Bacteria are able to integrate different (e.g. positive and negative) stimuli when given simultaneously.
7. Bacteria show purposeful (goal-oriented) behavior...
8. They communicate by means of pheromones (signaling molecules) and by exchanging genetic information (quasi-sexual behavior).
9. They co-operate and compete in both an intra- and interspecific way (i.e. with bacteria of the same and of other species).