Neurotransmitters are chemical messengers that coordinate the transmission of signals from one nerve cell (neuron) to the next.eurotransmitters are chemical messengers that coordinate the transmission of signals from one nerve cell (neuron) to the next.
Soldiers in the secondary zone may be boarded with 16 months time-in-service and four months time-in-grade as of the first day of the board month. The time-in-service requirement for attaining eligibility for promotion to SSG is 84 months Active Federal Service for the primary zone and 48 months for the secondary zone.
For second and subsequent encounters with similar antigens, secondary (anamnestic) immune responses occur. Here, the lag phase is shorter, and high and steady levels of antibodies are generated within a few days. This is due to antigen-specific memory T and B cells, originally produced during the primary response.