Lymph flows from the lymphatic capillaries toward the heart through a series of

Lymph flows from the lymphatic capillaries toward the

This preview shows page 1 - 3 out of 4 pages.

lymph. Lymph flows from the lymphatic capillaries toward the heart through a series of larger and larger lymphatic vessels until it reaches the two largest lymphatic ducts. The right lymphatic duct drains lymph into the right subclavian vein; the thoracic duct drains lymph into the left subclavian vein. What Causes Lymph to Move? Whereas blood moves because it is pumped by the heart, lymph depends on other means for movement. Lymph moves in response to the following:
Image of page 1

Subscribe to view the full document.

o The “milking” action of the skeletal muscles. As the skeletal muscles contract, they squeeze the surrounding lymphatic vessels thereby pushing lymph toward the heart. o The movement of the chest during respiration. Contraction and relaxation of the chest muscles cause changes in the pressure within the thoracic cavity. The changes in intrathoracic pressure increase the flow of lymph toward the subclavian veins. o The rhythmic contraction of the smooth muscle in the lymphatic vessels. The alternating contraction and relaxation of the smooth muscle cause lymph to flow. o The presence of valves. Like the veins, the lymphatic vessels contain valves. Valves prevent any backflow of lymph; if lymph moves at all, it must move toward the heart. The lymph node that receives the initial drainage is called the sentinel lymph node and is identified by the injection of dye Lymphatic Tissue Lymphatic tissue includes lymphatic organs and lymphatic nodules; the lymphatic organs are encapsulated masses of lymphatic tissue while the lymphatic nodules are partially or nonencapsulated. It is called lymphatic tissue because it contains lymphocytes and related cells. In general, lymphatic tissue helps defend the body against disease; it filters particles such as pathogens and cancer cells from the lymph, tissue fluid, and blood and supports the immune activities of the lymphocytes.
Image of page 2
Image of page 3
  • Fall '19
  • right lymphatic duct

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Ask Expert Tutors You can ask 0 bonus questions You can ask 0 questions (0 expire soon) You can ask 0 questions (will expire )
Answers in as fast as 15 minutes