Please be sure to eat all the food that is recommended on the Nutrisystem meal plan. You could be at risk of health issues if you do not maintain a healthy diet. 1  If you're pregnant, you may not join the Nutrisystem program.  If you're a nursing mother, you may not join the Nutrisystem program.
Quick Answer. According to The Free Dictionary, etiology, also spelled aetiology, is the study of exploration of the cause or factors contributing to something. In pathology, it specifically denotes the investigation into the cause or origins of a disease.
If the disease is not treated, however, it may progress to the stage where it causes subjective symptoms and abnormal physical findings. Therefore, the distinction be-tween asymptomatic and symptomatic disease is one of degree, depending primarily on the extent of the disease. The term etiology means cause. A disease of unknown etiology is one for which the cause is not yet known. Unfortunately, many diseases fall into this category. If the cause of a disease is known, the agent responsible is called the etiologic agent. The term pathogenesis refers to the manner by which a disease develops, and a pathogen is any microorganism, such as a bacterium or virus, that can cause disease. Classifications of Disease Diseases tend to fall into several large categories, although the diseases in a specific