What symptoms characterize acute radiation syndrome as a deterministic effect?

Acute radiation syndrome (ARS) is characterized by a specific set of symptoms that arise shortly after exposure to a high dose of ionizing radiation. The classic symptoms include nausea, vomiting, diarrhea, loss of appetite, and immune dysfunction. These symptoms occur due to the damage that high levels of radiation cause to rapidly dividing cells in the gastrointestinal tract and bone marrow, leading to bodily distress and impairment of the immune system.

Nausea and vomiting often occur within hours of exposure as the body’s response to cell damage starts manifesting. Diarrhea can result from the compromised function of the intestinal lining, while loss of appetite is a common symptom accompanying many forms of acute illness. Immune dysfunction arises from the depletion of bone marrow cells, which are essential for the production of blood cells integral to the immune response.

The other options present symptoms that are either more generalized or associated with other conditions rather than ARS. Fatigue, headaches, and skin-related issues typically arise from less acute radiation exposure or other types of illness.