Not to be confused with hemostasis. Homeostasis or homoeostasis (homeo- + -stasis) is the property of a system in which variables are regulated so that internal conditions remain stable and relatively constant. Examples of homeostasis include the regulation of temperature and the balance between acidity and alkalinity (pH). It is a process that maintains the stability of the human body's internal environment in response to changes in external conditions.
Allergies, also known as allergic diseases, are a number of conditions caused by hypersensitivity of the immune system to something in the environment that usually causes little problem in most people.
What Are the Symptoms of an Allergy? An allergy occurs when the bodyâs immune system sees a substance as harmful and overreacts to it. The symptoms that result are an allergic reaction. The substances that cause allergic reactions are allergens. Allergens can get into your body many ways to cause an allergic reaction. 1  You can inhale allergens into your nose and your lungs. 2  You can ingest allergens by mouth. 3  Your body can have allergens injected into it.  Your skin can absorb allergens.