In this procedure, the CS is paired with the US, but the US also occurs at other times. If this occurs, it is predicted that the US is likely to happen in the absence of the CS. In other words, the CS does not predict the US. In this case, conditioning fails and the CS does not come to elicit a CR.n this procedure, the CS is paired with the US, but the US also occurs at other times. If this occurs, it is predicted that the US is likely to happen in the absence of the CS. In other words, the CS does not predict the US. In this case, conditioning fails and the CS does not come to elicit a CR.
Nitrogen fixation is the process of nitrogen gas from the air  being turned into a compound in the soil by bacteria that live in  the root nodules of certain plants (legumes â¦).itrogen fixation which is the natural process of breaking down  nitrogen from atmosphere to ammonia NH3. It is done either  biologically or abiotically. This process is don â¦ e by bacteria.
Nitrogenase is an enzyme involved in nitrogen fixation and requires anaerobic conditions. Membranes within root nodules are able to provide these conditions. The rhizobacteria require oxygen to metabolize therefore oxygen is provided by a hemoglobin protein called leghemoglobin which is produced within the nodules.