Lesson 1C; homeostasis and feedback loops

what is homeostasis

maintaining the internal environment within physiological limits (ex. blood glucose levels)

what disrupts homeostasis

external stimuli (intense heat cold or lack of O2)

internal stimuli (psychological stress, exercise)

Disruptions are usually mild and temporary

what happens if homeostasis is not maintained

maybe death

What are the step of homeostasis and feedback loops

1. something disrupts homeostasis by increasing/decreasing a controlled condition

2. This condition is monitored by receptors that send out an input of nerve or chemical signals

3. these signals are received by a control center that than provides an output of nerve impulses or chemical signals

4. this output is brought to the effectors that bring about a change or response that alters the controlled condition back to optimal conditions.

what is negative feedback

a response that reverses or opposes the original stimulus (ex. blood pressure)

what is positive feedback

a activity that enhances the original stimulus (ex. childbirth)

Very few in human body