Hormones:the first step

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Examples of 'effect-orientated regulation' and 'concentration-orientated regulation'
Aldosterone is regulated by 'effect-oriented regulation'.

One of the target cells for the aldosterone secreted from the adrenal cortex, is the Na+ absorption from the kidney. Due to the command from the aldosterone, the activity of the Na+ pump is increased. The resultant elevation in blood pressure, is the hormonal effect of aldosterone. When the blood pressure is elevated, the aldosterone secretion is decreased via the negative feedback system, which decreases the activity of the Na+ pump in the kidney. Due to such regulation, the blood pressure is lowered towards the normal limits. On the other hand, when the blood pressure is lowered, the aldosterone secretion and the activity of the Na+ pump in the kidney are increased via the negative feedback system. Due to such regulation, the blood pressure is elevated towards the normal limits. In summary, the hormonal effect of aldosterone, namely the blood pressure elevation, is the 'result', which is being monitored and via the negative feedback system, controls the 'cause', or aldosterone secretion.

Examples of 'effect-orientated regulation' and 'concentration-orientated regulation'
The secretion of sex hormones from gonads and increase in plasma concentration of sex hormones are dependent on 'substances that stimulates the secretion of sex hormones'. 'Substances that stimulates the secretion of sex hormones' is the 'cause' and the 'secretion of sex hormones from gonads and increase in plasma concentration of sex hormones' is the 'result'. By increasing the plasma concentration of sex hormones, genital organs ( target organs) receives the orders from the hormone, and sexual development occurs.

It is the 'result' of the monitoring of the monitoring of the plasma concentration of sex hormones, and the 'substances that stimulates the secretion of sex hormones', which is the 'cause', is being controlled. If secretion of sex hormones and the plasma concentration of sex hormones decrease, then the 'substances that stimulates the secretion of sex hormones' due to negative feedback system. By this adjustment, the plasma concentration of sex hormones increase to normal level. On the other hand, if the plasma concentration of sex hormones increase, the 'substances that stimulates the secretion of sex hormones' decrease due to negative feedback system. By this adjustment, the plasma concentration of sex hormones decrease to normal level. The concentration of sex hormones are being monitored to keep them at a certain concentration, but the sexual development, the effect of the sex hormones, are not being monitored by the system that controls the secretion of sex hormones.

Achievement Quiz
1. The secretion of parathyroid hormone is controlled by the 'effect-oriented regulation'. And the effect of the parathyroid hormone is the increase in the plasma concentration of calcium. If the plasma concentration of calcium is too high, the secretion of parathyroid hormones [ a. increase / b. decrease ] .

2. If the plasma concentration of calcium decrease, the secretion of the parathyroid hormone [ a. increase / b. decrease ] .

3. If the secretion and the plasma concentration of parathyroid hormones increase, the plasma concentration of calcium [ a. increase / b. decrease ] D

4. Sex hormones are controlled by 'concentration-oriented regulation'. Does sexual development play a role in the negative feedback system? [ a. Yes, it does. / b. No, it doesn't. ]

5. The effect of the sex hormones is sexual development. Also, the secretion of the sex hormones are controlled by the 'concentration-oriented regulation'. Does the secretion of sex hormones decrease with sexual development? [ a. Yes, it does. / b. No, it doesn't. ]
Answer
1. The correct answer is b. If it is true, it will be the positive feedback system. It will increase the plasma concentration of calcium even more.

2. The correct answer is a. If it is true, it will be the positive feedback system. It will increase the plasma concentration of calcium even more.

3. The correct answer is a.

4. The correct answer is b. If it is true, it will be the positive feedback system. It will increase the plasma concentration of calcium even more.

5. The correct answer is b. If it is true, it will be the positive feedback system. It will increase the plasma concentration of calcium even more.
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