Answer: A Fixed Action Pattern
Explanation:
A fixed action pattern is an ethological term and off course a natural activity pattern that causes animals to act in a specific behavior pattern distinctive to their species. It is a pattern that is relatively unchangeable within the species and usually ends even when it is interrupted. You can say that, it is innate releasing mechanism or network where sign stimulus exists, once released from neural network; fixed action pattern leads to completion as well.
The early immune response to HIV-1 infection is likely to be an important factor in determining the clinical course of disease. Recent data indicate that the HIV-1 quasispecies that arise following a mucosal infection are usually derived from a single transmitted virus. Moreover, the finding that the first effective immune responses drive the selection of virus escape mutations provides insight into the earliest immune responses against the transmitted virus and their contributions to the control of acute viraemia. Strong innate and adaptive immune responses occur subsequently but they are too late to eliminate the infection. In this Review, we discuss recent studies on the kinetics and quality of early immune responses to HIV-1 and their implications for developing a successful preventive HIV-1 vaccine.
<span>The heavy metals and toxins could affect the food web and reduce biodiversity.
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The amount of population change due to immigration or emigration
