What is the primary function of the lymphatic system in animals?

The primary function of the lymphatic system in animals is to aid in immune response and transport lymph throughout the body. The lymphatic system is a crucial component of the immune system, as it helps to circulate lymph, a fluid that contains infection-fighting white blood cells. This system plays a vital role in identifying and fighting infections, as well as in the removal of waste products and excess fluids from body tissues.

Lymph nodes, found throughout the body, act as filtering stations for lymph, capturing pathogens and foreign substances, ensuring that they are attacked by immune cells. This not only helps protect the body from diseases but also helps maintain fluid balance within the tissues.

Other options like circulating blood, storing energy, and enhancing digestive processes pertain to different systems in the body. For example, blood circulation is primarily managed by the cardiovascular system, energy storage is mainly dealt with by the endocrine and metabolic systems, while digestive processes are regulated by the gastrointestinal system. Hence, the focus of the lymphatic system remains centered on immune function and lymph transport.