What is the system of vessels that takes up interstitial fluid and carries it as lymph to the blood?

• A. Lymph vascular system
• B. Cardiovascular system
• C. Digestive system
• D. Respiratory system

Answer: (A)

The lymphatic system collects interstitial fluid and returns it to the bloodstream as lymph. Interstitial fluid, which bathes tissues, enters tiny lymphatic capillaries and becomes lymph. It travels through progressively larger lymphatic vessels, is filtered by lymph nodes for immune surveillance, and is finally returned to the blood through the thoracic duct or the right lymphatic duct into the subclavian veins. This system helps maintain fluid balance and supports immune function. The cardiovascular (blood) system moves blood, not lymph; the digestive and respiratory systems have different primary roles, so they don’t perform this fluid-return function.