Lymphatic System

circulatory system

The lymphatic system is connected to the ______.

capillaries, vessels, ducts, and nodes

The lymphatic system consists of

back to the bloodstream.

The lymphatic system transports lymph one-way:

There is no pump, but the lymph moves via

skeletal muscle action, respiratory movement, and contraction of smooth muscle in vessel walls.

Functions of the Lymphatic System

1\.  Transports proteins and fluids, lost by capillary seepage, back to the bloodstream.

2\. Participates in the body’s immune response.

3\.  Is the pathway for the absorption of fats from the small intestine into the bloodstream.

Lymph

is clear, nearly colorless, alkaline fluid that occupies the space between all cells of the body. 

interstitial fluid

Lymph is termed _____ and is similar to blood plasma

95%, capillaries

Composed of __ water. It seeps in and out through the walls of very small vessels called _____

Functions of Lymph Nodes

filters, slows down, and cleans the lymph before returning it to the blood.

Lymph Nodes

Dark lumps on the membrane that trap and sometimes become swollen with bacteria that has invaded the body AND the white blood cells that fight that bacteria.

TRUE

The lymphatic system plays an important role in the development or spread of cancer. 

Lymphoma

Cancer that starts in the lymph nodes is called ***____.*** 

Metastatic Cancer

When cancer cells break off a tumor and spread into the lymph nodes, it is known as ***_______.***

Sentinel Node

Nearest node where the dye is injected

Spleen

is a soft, dark purple organ found in the upper-left portion of the abdomen and surrounded by blood and lymph vessels.

Red Pulp

The _____ of the spleen removes old red blood cells (erythrocytes) from the blood supply.

White Pulp

The ______ of the spleen removes, stores and produces white blood cells (lymphocytes).

Splenectomy

Surgical Removal of Spleen

Liver

Once the spleen is removed, majority of its functions are taken over by the _____

11-12cm or 4 1/2 inches

Normal length of spleen

Tonsils

Located in masses of tissue in the back of the throat, they filter bacteria and produce white blood cells. 

Tonsillectomy

Tonsils are sometimes removed if they become so large, they cause an obstruction or if they are chronically inflamed. Removal of Tonsils is called _____

Thymus

It manufactures one specific type of the infection-fighting lymphocytes called T-cells.

False

The thymus gland is not considered as part of the endocrine system but is actually part of the lymphatic system due to its appearance and function.  

Lymphocytes

The lymph nodes and spleen and thymus hold special WBC called ____

Lymphocytes

Can rapidly multiply and release antibodies in response to bacteria, viruses, and a range of other stimuli from dead or dying cells and abnormally behaving cells, like cancer

Granulocytes

Eosinophils, Basophils, Neutrophils

Two main types of Lymphocytes

B cells and T cells

B Cells

Produce Antibodies used to attack invading bacteria, viruses, and toxins

T Cell

Destroy the body’s own cells that have themselves taken over by viruses

Body Defenses

Nonspecific Defense System and Specific Defense System

Nonspecific Defense System

• Mechanisms protect against a variety of invaders

• Responds immediately to protect body from foreign materials

Specific Defense System

• Specific defense is required for each type of \n invader

• Also known as the immune system

First Line of Defense

Surface Membranes, Stomach Mucosa, Body Openings/Secretions

Second Line of Defense

Defensive Cells, Inflammatory Response, Antimicrobial Chemicals, Interferon, Fever

Skin

Physical Barrier to Foreign Materials

pH acidic, Sebum

• _____ to inhibit bacterial growth

• ______ is toxic to bacteria

Stomach mucosa

• Secretes hydrochloric acid

• Has protein-digesting enzymes

Body openings/ secretions

• Saliva and lacrimal fluid contain lysozyme

• Vaginal secretions are very acidic

• Mucus traps microorganisms

Defensive Cells

Phagocytes and Natural Killer Cells

Phagocytes

• (neutrophils macrophages)

• Engulfs foreign material into a vacuole

• Enzymes from lysosomes digest the material

Natural killer cells

• Can lyse and kill cancer cells

• Can destroy virus- infected cells

Inflammatory Response

Triggered when body tissues are injured, Results in a chain of events leading to protection and healing,

Functions of Inflammatory Response

• Prevents spread of damaging agents

• Disposes of cell debris and pathogens

• Sets the stage for repair

Cardinal Signs of Inflammatory Response

• Redness

• Heat

• Swelling

• Pain

Complement

• A group of at least 20 plasma proteins

• Activated when they encounter and attach to cells (complement fixation)

• Damage foreign cell surfaces

• Has vasodilators, chemotaxis, and opsonization

Interferon

• Secreted proteins of virus-infected cells

• Bind to healthy cell surfaces to inhibit viruses binding.

Fever

• Abnormally high body temperature

• Hypothalamus heat regulation can be reset by \n pyrogens (secreted by white blood cells)

• High temperatures inhibit the release of iron and zinc from liver and spleen needed by bacteria

• Fever also increases the speed of tissue repair