Physiology 2130 Lecture Notes - Lecture 1: Resting Potential, Axon Hillock, Electrochemical Gradient

• School: Western University
• Department: Physiology
• Course: Physiology 2130
• Professor: Anita Woods

Document Summary

Negative feedback loop controlled variable represses its own production. Positive feedback loop (difference is the controlled variable recognized by sensor but rather increases stimulation) Positive and negative feedback systems rely on the nervous and endocrine system to maintain homeostasis. Homeostasis the maintenance of relatively stable conditions within the external environment regardless of what is going on in the external environment. Internal environment- fluid in which our cells are bathed (interstitial fluid and blood plasma) External environment region outside the body but also includes spaces such as digestive, respiratory and urogenital tracts. The body is divided into two major fluid compartments. Intracellular fluid compartment (icf) [67% of tbw: extracellular fluid compartment (ecf) this makes up the internal environment of the body and can also be further divided into. , plasma watery portion of the blood [6. 6% of tbw] Interstitial fluid compartment bathing the cells [26. 4% of twb] Note the relative concentrations of ions in the intracellular fluid and the extracellular fluid compartment.