What term refers to organisms that promote and cause disease?

The term that refers to organisms that promote and cause disease is pathogens. Pathogens are typically microorganisms, such as bacteria, viruses, fungi, and parasites, that can invade the body and lead to illness. They disrupt normal biological functions and can elicit inflammatory responses from the host's immune system, which often manifests as symptoms of disease. Understanding the role of pathogens is crucial for studying diseases, including how they spread and how they can be controlled or prevented through various strategies such as vaccination or sanitation.

In contrast, the other terms relate to different biological functions: decomposers break down organic matter and recycle nutrients back into the ecosystem; autotrophs produce their own food through processes like photosynthesis and are essential to the food chain; and primary producers are organisms that create energy available for consumption by others, usually through photosynthesis. Each of these terms plays a critical role in ecological systems but does not relate to causing disease.