Which statement correctly pairs the direction of lymph flow with the lymph nodes?

Which statement correctly pairs the direction of lymph flow with the lymph nodes?

• A. Afferent vessels carry lymph toward the node; efferent vessels carry lymph away from the node
• B. Afferent vessels carry lymph away from the node; efferent toward the node
• C. They carry lymph in the bloodstream
• D. They are not connected to nodes

Answer: (A)

The main idea is how lymph moves through a lymph node. Lymph flows into a node via afferent vessels, where it is filtered by immune cells, and then exits through efferent vessels. This arrangement—afferent vessels carrying lymph toward the node and efferent vessels carrying lymph away from the node—lets the lymph be examined for pathogens and foreign material as it passes through the node, maximizing contact time for filtration. Lymph is separate from blood; it travels through the lymphatic system and only later re-enters the bloodstream via the thoracic duct or right lymphatic duct. So the direction described correctly reflects the flow through lymph nodes.

The main idea is how lymph moves through a lymph node. Lymph flows into a node via afferent vessels, where it is filtered by immune cells, and then exits through efferent vessels. This arrangement—afferent vessels carrying lymph toward the node and efferent vessels carrying lymph away from the node—lets the lymph be examined for pathogens and foreign material as it passes through the node, maximizing contact time for filtration. Lymph is separate from blood; it travels through the lymphatic system and only later re-enters the bloodstream via the thoracic duct or right lymphatic duct. So the direction described correctly reflects the flow through lymph nodes.