MICROANATOMY

Detailed explanation-1: -Most of the lymphatic vessels have valves like those in veins to keep the lymph, which can clot, flowing in the one direction (toward the heart). Lymphatic vessels drain fluid called lymph from tissues throughout the body and return the fluid to the venous system through two collecting ducts.

Detailed explanation-2: -Myocardial contractions help to propel cardiac lymphatic flow. During diastole, when the heart muscle relaxes, the ventricles fill with blood, and the resultant increase in chamber pressure drives the flow of lymph from the subendocardial to the myocardial lymphatics.

Detailed explanation-3: -The correct answer is A. Lymphatic vessels pass through lymph nodes. This allows the lymph to be filtered as it travels through the lymph nodes. The filtration system in the lymph nodes removes antibodies and pathogens and stimulates the immune responses as needed.

Detailed explanation-4: -Lymph enters a lymph node through several afferent lymphatic vessels. It then passes through the cortex, paracortex and medulla of the node, and exits on the opposite side through a single efferent lymphatic vessel.