By Regina Bailey. Definition: Homeostasis is the ability to maintain a constant internal environment in response to environmental changes. It is a unifying principle of biology. The nervous and endocrine systems control homeostasis in the body through feedback mechanisms involving various organs and organ systems.
Urticaria is the medical term for a type of allergic rash. Hives are the most common type of urticaria. Hives are itchy, pink to light red, raised blotches that are usually one-quarter to one-half inch in size.Hives can occur on any part of the body.ives are the most common type of urticaria. Hives are itchy, pink to light red, raised blotches that are usually one-quarter to one-half inch in size. Hives can occur on any part of the body.
Hives or urticaria are a type of rash consisting of itchy, swollen, red welts. The itching may be mild or severe. Foods, medications, infections, exercise, scratching, alcoholic beverages, emotional stress and many other factors may worsen hives.he most common cause of hives is infections. Foods such as eggs, nuts and shellfish are common causes of urticaria. Medications such as aspirin and antibiotics (especially penicillin and sulfa) also are common causes of hives. Infections causing hives include the common cold, and other viral infections.