Homeostasis Introduction
Homeostasis – the process of maintaining a constant internal environment despite changing external conditions
Homeostasis Ensures that the organs of the body operate within their normal limits and are working efficiently Based on a feedback system Information is sent to a control center which directs the organ to react accordingly
http://youtu.be/d2YWonZsh_M
Two Major Control Centers Brain – nervous system Glands – endocrine system
Several Factors (Activities) must be regulated to maintain homeostasis: 1. Temperature Skin Controlled by the hypothalamus
Several Factors (Activities) must be regulated to maintain homeostasis: 2. Heart Rate Heart Controlled by the medulla oblongata
Several Factors (Activities) must be regulated to maintain homeostasis: 3. Respiration Rate Ribs and Diaphragm Controlled by the medulla oblongata
Several Factors (Activities) must be regulated to maintain homeostasis: 4) Blood Pressure Heart and Arteries Controlled by the medulla (cardiac output, arteriole resistance) Kidneys Controlled by the hypothalamus which directs the pituitary gland to control water levels in the blood
Several Factors (Activities) must be regulated to maintain homeostasis: 5) Water Balance Kidneys Controlled by the hypothalamus which directs the pituitary gland
Several Factors (Activities) must be regulated to maintain homeostasis: 6) Blood sugar levels Pancreas Controlled by the Islet of Langerhands controls sugar levels Insulin – reduces blood sugar levels Glucagon – increase blood sugar levels
Several Factors (Activities) must be regulated to maintain homeostasis: 7) Detoxification Liver Controlled by the liver which removes harmful substances from the blood and inactivates them, returning them to the blood to be removed by the kidneys
Remember… in order to maintain homeostasis (process of maintaining a constant internal environment despite changing external conditions) these activities must be regulated by your control centers!!
Now to build up to these high function levels of organization in an organism that help maintain homeostasis let’s begin with the basic building blocks…