What best describes the components of the human lymphatic system?

The lymphatic system plays a crucial role in maintaining fluid balance in the body, facilitating the immune response, and transporting lymph, which contains infection-fighting white blood cells. The correct answer accurately identifies the key components of the human lymphatic system.

Lymph nodes are small, bean-shaped structures that act as filters for lymphatic fluid, trapping pathogens and facilitating their destruction by lymphocytes. Lymphatic vessels transport lymph throughout the body, connecting lymph nodes and ensuring that the fluid is circulated and filtered. The spleen is essential for filtering blood and producing lymphocytes, contributing to immune functioning. The thoracic duct is the largest lymphatic vessel, responsible for draining lymph from the majority of the body into the bloodstream.

The other options do not pertain to the lymphatic system. The heart and blood vessels are components of the circulatory system, responsible for blood transport. The kidneys and bladder are part of the urinary system that manage waste removal and fluid balance, while the brain and spinal cord are central components of the nervous system, involved in signal transmission and body coordination. Understanding the specific functions and structures of the lymphatic system is essential for recognizing its role in health and disease.