Question

Which of the following contribute(s) to the movement of lymph through lymphatic vessels?

the pumping of the heart
the milking action of skeletal muscle contraction
pressure changes in the thorax that result from breathing
both b and c

Answer 1

Lymphatic circulation is propelled by skeletal muscle contractions and thoracic pressure changes during breathing, thanks to one-way valves preventing backflow.

Step-by-step explanation:

The movement of lymph through lymphatic vessels is aided by factors other than the pumping of the heart. Specifically, lymph movement is facilitated by the milking action of skeletal muscle contractions and the pressure changes in the thorax that result from breathing. These actions help to push lymph through the vessels, which contain one-way valves to prevent backflow, ensuring that lymph flows toward the heart. It is then returned to the circulatory system via the lymphatic ducts at the junction of the jugular and subclavian veins.

The movement of lymph through lymphatic vessels is contributed by the milking action of skeletal muscle contraction and the pressure changes in the thorax that result from breathing. These two factors help propel the lymph through the lymphatic vessels and towards the heart. The pumping of the heart does not directly contribute to the movement of lymph.