The Lymphatic SystemThe Lymphatic System

As blood flows through your As blood flows through your cardiovascular system, fluid leaks cardiovascular system, fluid leaks out of the capillaries and mixes out of the capillaries and mixes with the fluid that bathes your with the fluid that bathes your

cells.cells.

To deal with this, your body’s To deal with this, your body’s lymphatic system collects the lymphatic system collects the

excess fluid and returns it to your excess fluid and returns it to your bloodblood

In addition, the lymphatic system In addition, the lymphatic system helps your body fight pathogenshelps your body fight pathogens

• The fluid collected by the lymphatic The fluid collected by the lymphatic system is transported through system is transported through vessels.vessels.

• The smallest vessels of the The smallest vessels of the lymphatic system are lymphatic system are lymph lymph capillariescapillaries

• Lymph capillaries absorb fluid and Lymph capillaries absorb fluid and any particles too large to enter the any particles too large to enter the blood capillaries.blood capillaries.

• The fluid and particles absorbed The fluid and particles absorbed into lymph capillaries are called into lymph capillaries are called lymphlymph

•Lymph Lymph capillariecapillaries along s along the spinal the spinal columncolumn

•Lymph is not pushed by a Lymph is not pushed by a pump. Instead, the pump. Instead, the squeezing of skeletal muscles squeezing of skeletal muscles provides the force to move provides the force to move lymph through vessels, and lymph through vessels, and valves help prevent backflowvalves help prevent backflow

•Lymph travels through your Lymph travels through your lymphatic system and then lymphatic system and then drains into large neck veins drains into large neck veins of the cardiovascular system.of the cardiovascular system.

• Lymph Nodes are small bean-Lymph Nodes are small bean-shaped organs where particles, shaped organs where particles, such as pathogens or dead such as pathogens or dead cells, are removed from the cells, are removed from the lymphlymph

• Lymph nodes contain many Lymph nodes contain many white blood cells. These WBC’s white blood cells. These WBC’s engulf or attach to pathogens engulf or attach to pathogens and mark them for destructionand mark them for destruction

• When the body becomes When the body becomes infected with bacteria or infected with bacteria or viruses, the WBC’s multiply and viruses, the WBC’s multiply and the nodes sometimes become the nodes sometimes become swollen and painful.swollen and painful.

ThymusThymus

• The thymus, The thymus, which is located which is located just above your just above your heart, releases heart, releases WBC’s.WBC’s.

• The WBC’s The WBC’s travel to other travel to other areas of the areas of the lymphatic lymphatic system.system.

SpleenSpleen• The largest organ is your The largest organ is your

spleen, which is located in spleen, which is located in the upper left side of your the upper left side of your abdomen.abdomen.

• The spleen filters blood The spleen filters blood and releases WBC’sand releases WBC’s

• When red blood cells are When red blood cells are squeezed through the squeezed through the spleen’s capillaries, the spleen’s capillaries, the older and more fragile older and more fragile cells rupture. For this cells rupture. For this reason, the spleen can be reason, the spleen can be thought of as the red-thought of as the red-blood–cell recycling center.blood–cell recycling center.

TonsilsTonsils• Tonsils are made up Tonsils are made up

of groups of of groups of lymphatic tissue lymphatic tissue located at the back of located at the back of your nasal cavity, on your nasal cavity, on the inside of your the inside of your throat, and at the throat, and at the back of your tongue.back of your tongue.

• WBC’s in the tonsils WBC’s in the tonsils defend the body defend the body against infectionagainst infection

• Tonsils sometimes Tonsils sometimes become badly become badly infected and must be infected and must be removed.removed.

• Tonsils and adenoids Tonsils and adenoids are masses of tissue are masses of tissue that are similar to the that are similar to the lymph nodes or lymph nodes or "glands" found in the "glands" found in the neck, groin, and neck, groin, and armpits. armpits.

• Tonsils are the two Tonsils are the two masses on the back of masses on the back of the throat. the throat.

• Adenoids are high in Adenoids are high in the throat behind the the throat behind the nose and the roof of nose and the roof of the mouth (soft palate) the mouth (soft palate) and are not visible and are not visible through the mouth through the mouth without special without special instruments. instruments.

• What is tonsillitis?What is tonsillitis?

Bacteria (bad germs) are tiny living things that can Bacteria (bad germs) are tiny living things that can cause sickness and infection. Too many bad germs on cause sickness and infection. Too many bad germs on your tonsils can make you sick. This is what your your tonsils can make you sick. This is what your doctor calls tonsillitis (ton-sil-lie-tis), or an infection doctor calls tonsillitis (ton-sil-lie-tis), or an infection in one or both of your tonsils. in one or both of your tonsils. Do you think you have tonsillitis? A symptom is a Do you think you have tonsillitis? A symptom is a signal that something is wrong with your body. Talk signal that something is wrong with your body. Talk with Mom and Dad if you see or feel: with Mom and Dad if you see or feel:

• Bright red tonsils Bright red tonsils • Yellow goo covering your tonsils Yellow goo covering your tonsils • A sore throat A sore throat • Pain when you swallow Pain when you swallow • Pain or swelling in your neck Pain or swelling in your neck • A hot forehead A hot forehead • Stinky breath even after you’ve Stinky breath even after you’ve

brushed your teethbrushed your teeth

• During a 24-hour period, approximately 20 During a 24-hour period, approximately 20 liters [5-1/4 gallons] of serumlike fluid passes liters [5-1/4 gallons] of serumlike fluid passes from the bloodstream to the tissues in the from the bloodstream to the tissues in the human body. This fluid bathes the cells, human body. This fluid bathes the cells, provides oxygen and nutrients, and carries provides oxygen and nutrients, and carries away metabolic byproducts (carbon dioxide, away metabolic byproducts (carbon dioxide, etc.) and toxins from the cells. Approximately etc.) and toxins from the cells. Approximately 85 percent of this watery fluid returns to the 85 percent of this watery fluid returns to the blood stream. The other 15 percent is blood stream. The other 15 percent is conveyed by the lymphatic system to the conveyed by the lymphatic system to the heart. Every 24 hours, the lymphatic system heart. Every 24 hours, the lymphatic system conveys approximately 284 centiliters [3/4 conveys approximately 284 centiliters [3/4 gallon] of this fluid to the heart. That's an gallon] of this fluid to the heart. That's an average of approximately one-half cup or 12 average of approximately one-half cup or 12 centiliters [4 fluid ounces] per hour.centiliters [4 fluid ounces] per hour.

• DID YOU KNOW THAT...DID YOU KNOW THAT...• Your body contains about 50% more lymphatic fluid Your body contains about 50% more lymphatic fluid

than blood.than blood. • Your lymphatic system contains over 600 collection sitesYour lymphatic system contains over 600 collection sites

called lymph nodes.called lymph nodes. • These nodes are formed at the junction sites of the These nodes are formed at the junction sites of the

lymph lymph vessel network.vessel network.

• Your lymphatic system is responsible for supplying Your lymphatic system is responsible for supplying plasm-richplasm-richprotein to your blood as well as carrying away toxins protein to your blood as well as carrying away toxins and other debris.and other debris.

• Your lymphatic system is your primary defense against Your lymphatic system is your primary defense against bacteria, viruses and fungus.bacteria, viruses and fungus.

• Most chronic (disease) problems occur at the junction of Most chronic (disease) problems occur at the junction of lymph vessels called lymph nodes.lymph vessels called lymph nodes.