Which body systems are primarily involved in the General Adaptation Syndrome?

• A. Digestive and circulatory systems
• B. Immune and lymphatic systems
• C. Nervous and endocrine systems
• D. Muscular and skeletal systems

Answer: (C)

General Adaptation Syndrome is about how the body responds to stress through nervous and endocrine systems. When a stressor is detected, the nervous system kicks in the immediate fight-or-flight response via the sympathetic branch, and the endocrine system engages through the hypothalamic-pituitary-adrenal axis. The hypothalamus releases hormones that stimulate the pituitary to secrete ACTH, which then prompts the adrenal glands to release cortisol and catecholamines. These signals work together to increase energy availability, sharpen focus, and sustain physiological readiness across the alarm and resistance stages, potentially leading to depletion in exhaustion if the stress continues. Immune and other systems are affected along the way, but the primary coordination comes from the nervous and endocrine systems.