lymphoid tissue that appears as a swelling of the mucosa in the oral cavity is called
A ring of lymphoid tissue that appears as a swelling of the mucosa in the oral cavity is called a(n). Tonsil. Explain why the lymphatic system is a one-way system, whereas the blood vascular system is a two-way system. Blood vessels form a complete circuit from and to the heart.edulla. Lymph enters the subcapular sinus of the lymph node through the ________. Afferent lymphatic vessels. As lymph exits the hilum there are fewer of these types of vessels draining the node than feeding it.