HSCI 180 Chapter 4: HSCI 180 CHAPTER 4
Document Summary
Homeostasis: maintenance of an environment of body functions within a certain range (e. g. temperature, blood and pressure); staying the same . Biochemical reactions basic to maintaining life are temperature dependent reactions occur near 37 degrees c. Body mechanisms occur to raise or lower temperature: sweating, shivering, altering blood flow etc. Homeostatic mechanisms regulate acidity, water and sodium content of the blood; glucose concentrations; other physical and chemical factors important to biochemical functioning. Vasopressin: antidiuretic hormone release inhibited by alcohol that increases excretion of urine. Two types of cells: glial (glia) and nerve (neurons) 10 to 50 times as many glia as neurons. Glial communicate with one another and with neurons, and modulate their activity. Intercommunicating astrocytes form a network that behave like a single unitary entity playing a major role in modulating neuronal activities. Glia cells provide firmness and structure to the brain, get nutrients into the system, eliminate waste and form myelin.