Biological agents refer to living organisms or their derivatives that are used for various purposes such as medical treatments, agriculture, bioremediation, and bioengineering. These agents can include bacteria, viruses, fungi, parasites, and other microorganisms. In the field of research, biological agents are studied for their potential applications in understanding biological processes, developing new therapies or treatments, and improving various industrial processes. Additionally, biological agents are also studied for their potential risks and hazards to human health and the environment.