Final answer:
A disease that affects the body as a whole due to under- or over-functioning is often related to endocrine system disorders like Cushing syndrome or autoimmune diseases such as rheumatoid arthritis.
Step-by-step explanation:
A disease that affects the body as a whole, often due to under- or over-functioning of the body's systems, is often related to disorders of the endocrine system or autoimmune conditions.
A disease involving the malfunction of glands that release hormones to regulate body functions can be due to either hypersecretion (too much hormone) or hyposecretion (not enough hormone), leading to various health issues.
Examples include Cushing syndrome from excess cortisol or Addison's disease from insufficient production of certain hormones. Similarly, immune system errors such as autoimmune diseases occur when the immune system attacks the body's own healthy cells, leading to diseases such as rheumatoid arthritis, systemic lupus erythematosus, and Grave's disease.