Examples of homeostasis include the regulation of body temperature, the pH of extracellular fluid, or the concentrations of sodium, potassium and calcium ions as well as that of glucose in the blood plasma, despite changes in the environment, diet, or level of activity.
Blue-collar workers perform labor jobs and typically work with their hands. The skills necessary for blue-collar work vary by occupation. Some blue-collar occupations require highly skilled personnel who are formally trained and certified.
Cervical collar. A cervical collar, also known as a neck brace, is a medical device used to support a person's neck. It is also used by emergency personnel for those who have had traumatic head or neck injuries, and can be used to treat chronic medical conditions. Whenever people have a traumatic head or neck injury, they may have a cervical fracture.