Lymphatic System Flashcards
It is a vast collection of cells and biochemicals that travel in lymphatic vessels. It is closely associated with the cardiovascular system. A network of vessels that assist in circulating fluids.
Lymphatic System
Organs of Lymphatic System
Lymph
Lymphatic Capillaries and Vessels
Lymphatic Tissues and Organs
Sites where stem cells divide; Provide a location for B and T lymphocytes to mature. Thymus and bone marrow.
Primary
Sites where most immune responses occur; lymph nodes, tonsils, peyer’s patches and spleen.
Secondary
Removes excess tissue fluid and returns it to the bloodstream.
Fluid balance
Approximately ____ of fluid pass from the blood capillaries into the interstitial fluid each day, whereas only ____ pass from the interstitial fluid back into the capillaries.
30 L
27 L
Instead, the 3 L of fluid enters the lymphatic capillaries, where it is called ______ and passes through the lymphatic vessels back to the blood.
lymph
If the extra 3 L of fluid were to remain in the interstitial fluid, _______ would result, causing tissue damage and eventual death.
edema
The lymphatic system absorbs lipids and other substances from the digestive tract through lymphatic vessels called lacteals.
Liquid absorption
Absorb digested fat and fat-soluble vitamin.
Lacteals
Lacteals: specialized lymph capillaries located in the villi of the small intestine that absorb? (and carry them to the general circulation)
digested fat and fat-soluble vitamins
Lipids enter the lacteals and pass through the lymphatic vessels to the?
venous circulation
The lymph passing through these lymphatic vessels, called ______, appears white because of its lipid content.
chyle
Pathogens are filtered from lymph by lymph nodes and from blood by the spleen.
Defense
In addition, ___________ and other cells are capable of destroying microorganisms and other foreign substances.
lymphocytes
Microorganisms and other foreign substances are filtered from lymph by ___________ and from blood by the _______.
lymph nodes
spleen
Because the lymphatic system fights infections, and filters blood and lymph to remove microorganisms, many infectious diseases produce symptoms associated with the?
lymphatic system and organs
That’s why usually if we have an infection the lymph nodes?
swell
- also known as intercellular fluid
- Acts as the intermediary between the blood in capillaries and the tissue.
- It diffuses from the capillaries into the tissue spaces.
Interstitial fluid
Because the fluid fills the surrounding spaces between tissue cells, it is also referred to as?
intercellular fluid
Most of this fluid is reabsorbed into the?
capillaries
When an excess fluid enters the lymphatic capillaries, it is called the?
lymph
If some of this fluid may not get reabsorbed, it can result in swelling of the tissue which is also known as EDEMA which is?
fluid accumulation in tissues
Give at least 3 Composition of Interstitial fluid.
Water
lymphocytes
some granulocytes
digestive nutrients
hormones
salts
carbon dioxide
urea
Composition of Interstitial fluid is similar in composition to?
blood plasma
Interstitial fluid carries metabolic waste products such as _______________ and ____________ away from the cells back into the capillaries for excretion.
carbon dioxide
urea wastes
It is a clear, colorless fluid that flows in only one direction toward the heart through the lymphatic vessels.
Lymph
Composition of Lymph
Water and solutes derived from 2 sources: substances in plasma and substances derived from cells.
Substances in plasma.
ions, nutrients, gasses and proteins
Substances derived from cells.
hormones, enzymes and waste products
- Run parallel to blood capillaries in all body tissues.
- Also made of simple squamous epithelium
- Allows diffusion of tissue fluid from interstitial spaces into the lymphatic pathway.
Lymphatic Capillaries
Lymphatic Capillaries is responsible for absorbing small chain fatty acids in the small intestine, using?
specialized lymphatic capillaries called lacteals
- Have thin walls and valves to prevent backflow.
- Filled with lymph.
- Larger vessels lead to lymph nodes and then to larger lymphatic trunks
Lymphatic Vessels
3 layers of Lymphatic Vessels
Endothelial lining
Smooth muscle
Connective tissue
Like veins, lymphatic vessels have thin walls and valves to prevent the?
fluid from flowing backwards
Lymphatic vessels are located in almost all of the tissues and organs that have?
blood vessels
As the lymphatic vessels progress on their path toward the heart, they?
converge to form larger and larger vessels
Periodically, these vessels lead to lymph nodes, where immune cells?
phagocytize bacteria
Then these lymphatic vessels continue to merge, eventually forming still larger lymphatic trunks, which?
drain major regions of the body
- Site of T lymphocytes maturation and production.
- Located in the superior mediastinum and is divided into a cortex and a medulla.
Thymus Gland
T and B lymphocytes develop from stem cells in red bone marrow.
Bone Marrow
Commonly called T cells.
T Lymphocytes
Before the T cells have fully matured, they leave the bone marrow and travel to the thymus gland, where they remain until?
fully functional
Once these T cells are immunocompetent or they are capable of recognizing antigens, they leave the thymus and migrate to lymphatic organs and tissues such as?
lymph nodes
spleen
tonsils
T cells that bind with specific antigens presented by macrophages.
Helper T cells
Kill virus-invaded body cells and cancerous body cells.
Killer T cells
- Commonly called B cells.
- Unlike T cells, these B cells remain in bone marrow until they are fully mature.
B Lymphocytes
Once they are mature, these B cells leave the bone marrow for ________________ and ____________, particularly the lymph nodes, spleen, bone marrow and mucus membrane.
lymphatic organs and tissues
B lymphocytes produce plasma cells that secrete?
antibodies
As the lymph is transported to the heart, it passes through multiple lymph nodes. It removes pathogens and other foreign material. This is why most of us will get swollen lymph nodes during an active infection.
Secondary Lymphoid Tissue and Organ
Besides cleansing lymph, lymph nodes also serve as sites for final maturation of some types of?
lymphocytes and monocytes
- Tiny oval-shaped structures.
- Covered by a capsule of fibrous connective tissue.
- Filter potentially harmful particles from the lymph.
Lymph Nodes
Lymph Nodes produce lymphocytes to destroy?
invading bacteria
Small masses of lymphatic tissues located along the course of _______________ through which lymph is filtered on its way to the venous system.
lymphatic vessels
It is covered by a capsule of fibrous connective tissue that extends into the node. These capsular extensions are called?
trabeculae
A less dense area at the center called ______________ which produces the lymphocytes when an infection is present.
germinal centers
_________ are spaces between the lymph tissue that contain a network of fibers and the macrophage cells. Lymph slowly flows through these sinuses in the process of being filtered.
Sinuses
As lymph enters the node through the _____________, the immune response is activated.
afferent lymphatic vessel
Any microorganisms or foreign substances in the lymph __________ the germinal centers to produce lymphocytes, which are then released into the lymph.
stimulate
After slowly filtering through the node, lymph leaves through a single?
efferent lymphatic vessel
Eventually, the lymphocytes reach the blood and produce antibodies _________ the microorganisms.
against
Each lymph node is attached to an __________ where lymph enters the lymph node, and to a different l.v. where lymph exits.
afferent lymph vessels
Cortex (B cells) & Paracortex (T cells) has what cells?
Immunocytes
Medulla has what cells?
Phagocyte (macrophages)
- Found in the neck.
- Monitor lymph coming from the head and neck.
Cervical Lymph Nodes
- Clustered in armpit.
- Receive lymph from the arm and breast.
Axillary Lymph Nodes
- Occur in the groin.
- Receive lymph from the legs.
Inguinal Lymph Nodes
2 regions of lymph nodes in the body
The lymphatic duct and the thoracic duct.
The _____ and _____ drain into the lymphatic duct and the rest of the body goes through the thoracic duct.
head
neck
Dense arrangement of lymph tissue lacking a distinct boundary.
Lymphatic Nodules
The lymphatic tissue of the node consists of different kinds of lymphocytes and other cells that make up ______________of tissue called lymph nodules.
dense masses
- Capable of producing lymphocytes and filtering bacteria.
- Groups of lymphatic nodules in the oral cavity and nasopharynx that are capable of producing lymphocytes and filtering bacteria.
Tonsils
Tonsils trap foreign ___________before they enter the body.
pathogens
Located on the sides of the soft palate.
Palatine
Also called adenoids, sits on the wall of the pharynx.
Pharyngeal
May be found at the back of the tongue.
Lingual
- Largest lymphatic organ.
- Is in the upper left quadrant of the abdomen, just inferior to the diaphragm.
- Surrounded by a fibrous capsule.
Spleen
Spleen stores large amounts of?
red blood cells
During excessive bleeding or vigorous exercise, the spleen _________, forcing the stored red blood cells into circulation.
contracts
Contains compact masses of lymphocytes; where foreign substances stimulate lymphocytes.
White pulp
Consist of a network of erythrocyte-filled sinuses and phagocytic cells; where foreign substances and defective RBCs are removed from the blood by phagocytes.
Red pulp
- Also known as aggregated lymphatic follicles.
- Found in the lumen of the terminal end of the ileum.
Peyer’s Patches
Peyer’s Patches produce?
macrophages
Macrophages destroy bacteria and prevent bacteria from penetrating the?
walls of the small intestine
Other lymphoid organs include the?
appendix
Thymus, lymph nodes and spleen are considered organs because each is surrounded by a?
connective tissue capsule
Lymph travels in only how many direction?
1
________________ of tissue fluid drives the lymph into the lymphatic capillaries.
Hydrostatic pressure
Lymphatic capillaries collect fluid between?
cells and blood capillaries
Formed by the convergence of larger lymphatic vessels called lymphatic trunks.
Collecting Ducts
- Also known as thoracic duct.
- Empties the lymph from the rest of the body to the left subclavian vein.
Left Lymphatic Duct
Empties the lymph from the right upper area of the body to the right subclavian vein
Right Lymphatic Duct
Lymphatic Flow 1: Unlike the circulatory system, which travels in closed circuits through the blood vessels, lymph travels in only one direction: from?
the body organs to the hearT
Lymphatic Flow 2: It is an open circuit where lymphatic capillaries in body tissues reabsorb ________________ which is derived from blood plasma.
excessive tissue fluid
Lymphatic Flow 3: It does not flow continuously through vessels forming a?
closed circular route
Lymphatic Flow 4: Tissue fluid is transported from lymphatic capillaries to?
lymphatic collecting vessels
Lymphatic Flow 5: Then it enters the _______ through the afferent lymph vessels.
nodes
Lymphatic Flow 6: Then the lymph is filtered inside the lymph node then exits the node through the?
efferent lymph vessels to the lymphatic trunks
Lymphatic Flow 7: And finally into collecting ducts where the lymph is disposed into the venous system specifically into the?
subclavian veins
- Inflammation or swelling of the lymph nodes.
- If harmful substances occur in such large quantities that they cannot be destroyed by the lymphocytes, the node becomes inflamed.
Lymphadenitis
Tonsils are frequently _______ and __________, and cause difficulty in swallowing, severe sore throat, elevated temperature, and chills.
infected
enlarged
Lymphadenitis may be treated with?
Antibiotics
- Swelling of the tissues due to an abnormal collection of lymph.
- Caused by damage to the lymph system that prevents lymph from draining properly.
Lymphedema
Disease caused by the Epstein-Barr virus.
Infectious Mononucleosis
- Cancer of lymphocytes.
- Lymphocytes change and grow out of control.
Lymphoma
Lymphoma often begins in?
Lymph nodes
Tumor of the lymphatic tissue, usually?
malignant
Usually begins as a large mass with?
no associated pain
The enlarged nodes will __________ surrounding structures and cause complications.
compress
This type Lymphoma distinguished from other lymphoma by the presence of large cancerous lymphocytes known as reed-sternberg cells.
Hodgkin’s Lymphoma
Give another type of Lymphoma aside from Hodgkin’s Lymphoma.
Non-Hodgkin’s Lymphoma
- Parasitic disease.
- The adult worms live in the human lymphatic system.
Lymphatic Filariasis
Lymphatic Filariasis’s parasite.
Wuchereria bancrofti or Brugia malayi
People with Lymphatic Filariasis can suffer from?
lymphedema
elephantiasis
hydrocele
