Negative feedback in the body is some unpleasant feeling. By feeling uncomfortable you are likely to remedy the situation. Seek warmth or cool off.Why does controlling body temperature involve negative feedback?
HEHE you have the same name as me!!
Negative feedback means that as one thing changes in one direction, another changes in the opposite direction. So, as one thing goes up, it causes something else to go down.
Consider the hormone thyroxin which is produced by the thyroid gland. Thyroxin effects the rate of metabolism.
To stimulate the thyroid gland to make thyroxin, an important gland that is attached to the brain, the pituitary gland (real name is the hypophysis) releases a hormone to stimulate the thyroid. That hormone is called Thyroid Stimulating Hormone ... abbreviated THS. As THS goes up, so does the production of thyroxin.
However, thyroxin has the opposite effect on the pituitary and is, therefore, called a negative feedback. Thyroxin causes the pituitary to STOP (or slow down) the production of THS.
Without THS, the thyroid stops or slows its production of thyroxin.
Without thyroxin, there is no message to the pituitary to stop making THS and the pituitary will, therefore, START to make THS.
So, now the thyroid begins to make THS and the whole cycle starts over. Thyroxin is a negative feedback to the pituitary.
This negative feedback system keeps the production of substances (in my example it is the production of tyroxin) in balance.
Here is a summary of what was presented:
As substance #1 goes up, substance #2 goes up.
As substance #2 goes up, substance #1 goes down.
As substance #1 goes down, substance #2 goes down.
As substance #2 goes down, substance #1 goes up so, there is negative feedback.
think thermostat - theyre essentially homologous
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