Download 2.3.2 Lymph circulatory system

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2.3.2 Lymph circulatory system
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Daniel Williamson
This work is produced by OpenStax-CNX and licensed under the
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Creative Commons Attribution License 3.0
1 Lymph Circulatory System
Comparison of lymph and blood system: http://www.lymphnotes.com/article.php/id/150/ 1
Short videos on lymph: http://www.nlm.nih.gov/medlineplus/ency/article/002247.htm 2
YouTube video on lymph system: http://www.youtube.com/watch?v=qTXTDqvPnRk 3
1.1 Composition of the lymphatic system
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The lymphatic system is composed of lymph vessels, lymph nodes, and organs.
The organs associated with the lymphatic system are the spleen and thymus.
The spleen is the boundary between the blood and the lymphatic system.
Knots of lymphatic tissue in the spleen add lymphocytes to the blood.
The spleen also acts as a lter for the blood, and helps to destroy worn out red-blood cells.
In the event of damage to the spleen, it can be removed and its functions will be carried out by the
liver, the bone marrow and the lymph nodes.
Most of the disease-ghting function of the adult mammal is carried out by the lymph nodes which
occur along the lymph ducts.
Lymph nodes are small irregularly shaped masses through which lymph vessels ow.
Clusters of nodes occur in the armpits, groin, and neck.
Cells of the immune system line channels through the nodes and attack bacteria and viruses traveling
in the lymph so they basically act as tiny lters.
So. . .
• Lymph vessels are located as a network throughout all tissues in the body.
• Lymph vessels assist the circulatory system and all the cells of the body by removing
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wastes, germs
and excess water from the tissue uid.
Lymph vessels carry lymph uid in ONE direction only , from the bottom of the body up towards
the heart.
Valves prevent the lymph uid from owing backwards.
Muscle contractions push the uid upwards.
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1.1: Feb 16, 2012 4:07 pm -0600
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1 http://www.lymphnotes.com/article.php/id/150/
2 http://www.nlm.nih.gov/medlineplus/ency/article/002247.htm
3 http://www.youtube.com/watch?v=qTXTDqvPnRk
http://cnx.org/content/m43110/1.1/
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1.2 Functions of lymphatic system
The main functions of the lymphatic system are as follows:
collect and transport tissue uids from the
intercellular spaces in all the tissues of the body, back to the veins in the blood system;
it plays an important role in returning plasma proteins to the bloodstream ;
digested fats are absorbed and then transported from the villi in the small intestine to the
bloodstream via the lacteals and lymph vessels.
new lymphocytes are manufactured in the lymph nodes ;
antibodies and anti (manufactures in the lymph nodes) assist the body to build up an eective
immunity to infectious diseases ;
lymph nodes play an important role in the defence mechanism of the body . They lter out
micro-organisms (such as bacteria) and foreign substances such as toxins, etc.
it transports large molecular compounds (such as enzymes and hormones) from their manufactured
sites to the bloodstream.
• the main function of the lymphatic system is to
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Youtube videos on lymph http://www.youtube.com/embed/Kh-XdNnTZUo4
1.3 Relationship between blood system and lymphatic system
Table of comparison between the cardiovascular system and the lymphatic system
Cardiovascular System (Blood)
Lymphatic System (Lymph)
Blood is responsible for collecting and distributing
oxygen, nutrients and hormones to the tissues of
entire body.
Lymph is responsible for collecting and removing
waste products left behind in the tissues.
Blood ows in the arteries, capillaries, and veins.
Lymph ows in an open circuit from the tissues
into lymphatic vessels.
Blood ows towards the heart and away from the
heart
Lymph ows in one direction only (towards the
heart)
Blood is pumped by the heart to all parts of the
body
Lymph is not pumped. It passively ows from the
tissues into the lymph capillaries.
Blood consists of the liquid plasma that transports
the red and white blood cells and platelets.
Lymph that has been ltered and is ready to return to the cardiovascular system is a clear or milky
white uid.
Blood is visible and damage to blood vessels causes
obvious signs such as bleeding or bruising.
Lymph is invisible and damage to the lymphatic
system is dicult to detect until swelling occurs.
Blood is ltered by the kidneys.
Lymph is ltered by lymph nodes located throughout the body..
Table 1
4 http://www.youtube.com/embed/Kh-XdNnTZUo
http://cnx.org/content/m43110/1.1/