Saturday, June 7, 2008

Fig. 2 Principle Of A Feedback Mechanism In

Fig. 2 Principle of a feedback mechanism in to system. - gland-regulator; And - working gland; 1 and 2 - regulating hormones; 1 and 2 - working hormones. The mechanism of a negative feedback: at increase in activity of gland And concentration of a working hormone a1 which activity of a regulator Would brake increases that in turn leads to decrease in concentration of regulating hormone 1 and accordingly to decrease in activity of gland And. The mechanism of a positive feedback: the increase in signal strength X Would increase activity of a regulator that increases level of regulating hormone 2 and, in turn, increases level of working hormone 2. Last causes the further stimulation of activity of regulator 1 etc. If stability of the internal environment - an indispensable condition of a free life of an organism an indispensable condition of development of an organism is the programmed infringement of stability. Accordingly along with the law of a constancy of the internal environment there is a law of a deviation of a homeostasis.