Biological sources refer to materials derived from living organisms, including plants, animals, and microorganisms. These sources provide essential resources such as food, medicine, and raw materials. For example, plants are used for their fruits, vegetables, and fibers, while animals contribute meat, dairy, and leather products. In addition to direct consumption, biological sources play a crucial role in various industries. Microorganisms are utilized in biotechnology for producing enzymes, antibiotics, and biofuels. Overall, biological sources are vital for sustaining life and supporting economic activities across the globe.