Answer:presence and absence
Explanation:Schizophrenia is a mental disorder that affects how a person thinks, feels, and behaves,it lasts long (chronic) in most persons and always severe It is believed to be HEREDITARY,although some scientific evidence show it is also ENVIRONMENTAL, Contact with VIRUSES, MALNUTRITION BEFORE BIRTH,PSYCHOLOGICAL AND SOCIAL factors can be responsible. Affected persons also appear confused and always act abnormally.Schizophrenia is less common compared to other mental disorder but it is always more devastating and disabling.