Hormones:the first step

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There are two types of negative feedback regulation in hormonal secretion. The "effect-orientated regulation", in which the hormonal effects are being monitored and stabilized, and "concentration-orientated regulation", in which the hormonal concentration in the plasma are being monitored and stabilized.

"Effect-orientated regulation" and "concentration-orientated regulation"
The "effect-orientated regulation" (left figure)

Hormone is secreted, the plasma hormonal concentration is elevated, the target cell receives the command and a certain 'hormonal-effect' takes place. The secretion and increase in hormonal concentration is the 'cause' and the hormonal effect is the 'result' in the feedback system. Namely, the hormonal effect is being monitored and via the negative feedback system, regulates hormonal concentration. Thus, when the hormonal effect is decreased, the hormonal secretion is increased and the plasma concentration is elevated. Because of this regulation, the target cell receives increased command, and more hormonal-effect takes place. In reverse, when the hormonal effect is increased, the hormonal secretion is decreased. Because of this regulation, the target cell receive decreased command, and less hormonal-effect takes place.

The "concentration-orientated regulation" (right figure)

There is a 'stimulant of hormonal secretion'. As a result, hormone is secreted, the plasma hormonal concentration is elevated,the target cell receives increased command and a certain 'hormonal-effect' takes place. This 'stimulant of hormonal secretion' is the 'cause' and the secretion and increase in hormonal concentration is the 'result'. Namely, the hormonal concentration is being monitored and via the negative feedback system, regulates the 'stimulant of hormonal secretion'. Thus, when the hormonal concentration is decreased, the 'stimulant of hormonal secretion' is increased and the plasma concentration is elevated towards the normal range. In reverse, when the hormonal concentration is increased, the 'stimulant of hormonal secretion' is decreased and the plasma hormonal concentration is lowered towards the normal range. This is a system in which hormonal concentration in the plasma is being monitored and stabilized.

Achievement Quiz
1. When hormonal effect of a hormone regulated by the "effect-orientated regulation" increases, then hormonal secretion is [ a. decreased / b. increased ] .

2. When the hormonal effect of a hormone regulated by the "effect-orientated regulation" decreases, then hormonal secretion is [ a. decreased / b. increased ] .

3. Hormonal concentration of a hormone regulated by 'concentration-oriented regulation' is being monitored and stabilized. [ a. right / b. wrong ]

4. Hormonal concentration of a hormone regulated by 'effect-oriented regulation' is being monitored and stabilized. [ a. right / b. wrong ]
Answer
1. The correct answer is a. This is the positive feedback which will explained later on in the text.
2. The correct answer is b.
3. The correct answer is a. Please go over the text again.
4. The correct answer is b.
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