Lymphatic System

1. Lymphatic system consists of lymph, lymph vessels, lymph nodes, and lymph tissue

2. Works with the circulatory system

3. Removes waste and excess fluid from the tissues

Overview:

1. Thin, watery fluid 2. Composed of intercellular or

interstitial fluid that forms when plasma diffuses into tissue spaces.

3. Composed of water, digested nutrients, salts, hormones, oxygen, carbon dioxide, lymphocytes, and metabolic wastes such as urea

4. When fluid enters lymphatic system, be comes known as lymph

Lymph

1. Located throughout the body in almost all tissues that have blood vessels

Lymphatic Vessels/”Lymphatics”

a. Small, open-ended lymph vessels

b. Act like drainpipesc. Pick up lymph at tissues throughout the body

d. Capillaries join together to form larger lymphatic vessels

Lymphatic Capillaries

Lymphatic vessels carry lymph Contractions of skeletal muscles against lymph vessels cause lymph to flow through vessels

Vessels pass through lymph nodes

Contain valves that keep the lymph flowing one way – towards the heart

Lymphatic Vessels cont:

Specialized lymphatic capillaries, called lacteals, located in area of small intestine

a. Pick up digested fats or lipids b. When lymph is mixed with the lipids it is called chyle

c. Lacteals transport the chyle to the blood stream through the thoracic duct

Lacteals

Popularly called “glands”

Located all over the body usually in groups or clusters – principal groupings are located in the neck, armpits, chest, abdomen, pelvis, and groin

Small, oval masses ranging in size from a pinhead to an almond

Lymph Nodes

http://www.youtube.com/watch?v=Kh-XdNnTZUo

Lymph vessels bring lymph to the nodes

Nodes filter the lymph and remove impurities such as:CarbonCancer cellsPathogens or disease producing

organ Dead blood cells

Lymph Nodes cont:

Lymphatic tissue in nodes also produces substances such as:Lymphocytes: a type of leukocyte or

white blood cellAntibodies: substances used to combat

infectionF. Purified lymph, with lymphocytes

and antibodies added, leaves the lymph node by one or two lymphatic vessels

Lymph Nodes cont:

As lymphatic vessels leave the lymph nodes, they continue to join together to form larger lymph vessels

Eventually they drain into one of two lymphatic ducts: the right lymphatic duct or the thoracic duct

Lymphatic Ducts

Short tubeReceives all the

purified lymph from the right side of the head and neck, the right chest, and the right arm

Empties into the right subclavian vein, returning the purified lymph to the blood

Right Lymphatic Duct

Much larger tubeDrains the lymph

from the rest of the body

Empties into the left subclavian vein

Enlarged pouchlike structure called the cisterna chyli is located at the start of the thoracic duct

Thoracic Duct

Serves as a storage area for purified lymph

Receives chyle from the intestinal lacteals

Cisterna Chyli

Located throughout the body in addition to being in the lymph nodes

Tonsils, spleen, and thymus are examples of lymphatic tissue

Lymph Tissue

Masses of lymph tissueFilter interstitial fluidThree pairs of tonsils

Palatine tonsils on each side of the soft palate

Pharyngeal tonsils (also called adenoids) located in the nasopharynx (upper part of the throat)

Lingual tonsils on the back of the tongue

Tonsils

Organ located on the left side in back of the upper part of the stomach

Produces leukocytes and antibodies

Destroys old erythrocytes or red blood cells

Spleen

Stores erythrocytes to release into blood stream if excessive bleeding occurs

Destroys thrombocytes or plateletsFilters some metabolites and wastes

from tissueshttp://

www.youtube.com/watch?v=0CqWulccLMo

Spleen

Mass of lymph tissue located in the center of the upper chest

Atrophies or wastes away after puberty and is replaced by fat and connective tissue

Thymus

Functions during early lifeProduces antibodiesManufactures lymphocytes to fight

infectionFunction is taken over by lymph

nodes after it atrophieshttp://

www.youtube.com/watch?v=fFXQV-XJf3M

Thymus