Question

1. List 10 body mechanisms that are maintained in homeostasis by negative feedback. Why does positive feedback usually lead to disease or death? Describe two exceptions to positive feedback leading to disease or death.

Answer 1

The composition of the internal environment is tightly controlled, and this fairly constant state is called "homeostasis". Mechanisms:-. 1)control of body temperature. 2) maintenance of pH of blood glucose-. 3) stomach maintenance pH of surrounding organs 4) cooling down mechanism. 5) heating up mechanism. 6) maintenance of blood glucose-. 7) sweating 8) heavy breathing. 9) shivering. 10) increase the release of hormones Positive feedback is harmful or even Life threatening process.because it self amplifying nature and can quickly change the internal state of the body. Example: fever triggered by infection------ body temperature rises------------increased matabolic rate----------------body produce heat faster than it can get rid of it---------metabolic rate and temperature rises much above 42°c(108°f).--------------this vicious circle become fatal--- requires emergency medical treatment... During labour a hormone called oxytocin is released that intensifies and speeds up contractions causes more oxytocin to be released and the cycle goes until the baby is born.the birth ends the release of oxytocin and ends the positive feedback mechanism.thank u