Chapter 22 Lymphatic system Flashcards
What are the functions of the lymphatic system?
drain interstitial fluid, transport dietary lipids absorbed by the GI tract, facilitate immune response
What components make up the lymphatic system?
lymphatic capillaries, lymphatic vessels, lymph nodes, lymphatic trunks, lymphatic ducts, thymus, bone marrow, spleen, tonsils, lymph nodes and thoracic ducts
What is the difference between lymph and plasma
plasma carries proteins, lymph does not
What drives lymph movement into the lymphatic capillaries
lymph fluid is the fluid that is remaining in the interstitial fluid and is driving into the lymphatic system via hydrostatic pressure
List the order of the lymphatic pathway beginning with the lymphatic capillaries and ending with the emptying into the subclavian veins.
lymphatic capillaries, lymphatic vessels, lymph nodes, lymphatic trunks, collecting ducts and subclavian veins
List the two collecting ducts and where they empty.
Right lymphatic duct empties into the right subclavian. Thoracic duct empties into the left subclavian.
Of the collecting ducts, which one is longer and larger?
thoracic duct
Describe a lymphatic capillary and a lymphatic vein.
Lymphatic capillaries are a bit larger than blood capillaries and have a unique one-way structure. Lymphatic vessels resemble blood veins in structure but have thinner walls and more valves.
How are lymphatic veins similar to cardiovascular veins?
they have vessels and require assistance to push lymph throughout the system
Explain the obstruction of movement of lymph
Lymphatic fluid is moved by pressure in the interstitial space and the milking action of the skeletal muscle contraction and respiratory movements. An obstruction or malfunction of lymph flow leads to edema.
List the primary lymph organs
red bone marrow and thymus
What does immunocompetent mean?
the stem cell is capable of mounting an immune response
List the secondary lymphatic organs
spleen, lymph nodes and tonsils
What is/are the main function(s) of the thymus
the maturation and education of T-cells
What happens to the thymus when one ages
it shrinks
what is the function of the lymph node
filters lymph
What is the function of the red pulp of the spleen? White pulp?
The spleen filters blood. The red pulp stores platelets and old RBC’s are destroyed. The white pulp consists of WBC’s that carry out immune function.
Differentiate between innate (non-specific) and adaptive (specific) defenses.
The innate defense is non-specific and non-adaptive and is present at birth. The adaptive immunity defense is the ability of the body to adapt defenses against the antigens of specific bacteria, virus, foreign tissues, even toxins.
List the 5 steps of phagocytosis
chemotaxis, adherence, ingestion, digestion and killing
How does fever contribute to the non-specific (innate) response
speeds up body reactions, increases the effects of endogenous antimicrobials, sequesters nutrients from microbes
What is inflammation
defensive response of almost all body tissues to damage of any kind
What are the 4 characteristic signs of inflammation
redness, pain, heat and swelling
What are the three stages of inflammation
vasodilation, emigration, tissue repair
What is the difference between antigens and antibodies
Antigens are substances that provoke an immune response in the body, they are foreign to the body. Antibodies are produced to “mark” the antigen for destruction
What are 2 properties distinguish adaptive versus innate immunity
specificity and memory
What are antigen-presenting cells (APC’S)? Give examples
These cells “present” the antigen to show the body what to look for. Examples are macrophages, B-cells and dendritic cells
What is a helper T (CD4)?
The “commander” cell
What is a cytotoxic T (CD8) cell and what does it do?
It destroys the antigen and creates memory cytotoxic cells
Explain the difference between the cellular immune response and the humoral response
Cell-mediated immunity is driven by the cells. It is the process of CD4 communicating with CD8 to destroy the antigen. Humoral response is when CD4 cell communicates with the B-cell producing memory B-cells and plasma cells. The plasma cells create antibodies
What is a plasma cell
A B-cell that creates antibodies
What are the MHC molecules
markers on the cell body
Where are MHC class 1 (MHC-I) molecules found?
almost on all body cells
Where are MHC class II (MHC-II) molecules found?
Only on antigen present cells (APC’s)
What is meant by clonal selection
When a white blood cell proliferates and differentiates in response to a specific antigen
What are effector cells
active helper T cells, active cytotoxic T cells, plasma cells
What are memory cells
Do not participate in the initial immune response but are able to respond to a subsequent exposure- proliferating and differentiating into more effector and memory cells
What are cytokines
chemicals that send a signal or communicate to another cell (ex- interleukin 1)
List three methods of how antibodies work
neutralizing a bacterial or viral antibody, or a toxin by covering the binding sites and causing agglutination and precipitation; activating the classical complement pathway; enhancing phagocytosis
What are the five antibody types
IgG, IgA, IgM, IgE, IgD
What is important about IgG
main antibody body found in the body, crosses the placental barrier; secondary response and remains for life
What is important about IgA
found in secretions; why breast milk is important
What is important about IgM
primary response; 1st antibody we make; it is made quickly and does not last in our body long
What is important about IgE
found in allergic reactions; causes eosinophils/basophils to release histamine
What is important about IgD
no idea what it does
Explain the difference between primary immune response and secondary immune response
Primary immune is response if from the first exposure to an antigen. IgM is produced. Secondary immune is response from a second exposure from an antigen, IgG is used.
What is meant by naturally acquired active immunity?
acquired a disease and produced your own antibodies (IgG)
What is meant by artificially acquired active immunity
artificially acquired the disease but you made your own antibodies (flu-shot)
What is meant by naturally acquired passive immunity
got the antibody but didn’t stay- breastfeeding
What is meant by artificially acquired passive immunity
acquire disease from an outside source, get some else’s antibodies
What is an allergic reaction?
an overreaction of the immune system
What is meant by immunodeficiency?
the immune system is not working properly
What is meant by autoimmunity?
the immune system attacks itself
What does auto- mean?
self
What does immune- mean?
free, exempt
What does -gen mean?
become, be produced
What does humor- mean?
moisture, fluid
What does nod- mean?
knot
What does patho- mean?
disease, sickness
List examples of innate mechanisms
External, physical and chemical barriers provided by the skin and mucous membranes. It also includes various internal defenses, such as antimicrobial substances, natural killer cells, phagocytes, inflammation and fever
What do physical barriers do in regards to innate mechanisms?
physical barriers keep antigens out
What do interferons do?
protect uninfected host cells from viral infection
What does complement do?
“candy coats” bacteria so it is easier to swallow for phagocytes (opsonization) and punches holes in the bacteria to help destroy them
How does cilia contribute to innate defenses?
trap and remove microbes and dust from upper respiratory tract
How does lacrimal apparatus contribute to innate defenses?
tears dilute and wash away irritating substances and microbes
How does saliva contribute to innate defenses?
washes microbes from surfaces of teeth and mucous membranes from mouth
How does urine contribute to innate defenses?
washes microbes from urethra
How does defecation/vomiting contribute to innate defenses?
expel microbes from body
How does sebum contribute to innate defenses?
forms protective acidic film over skin surface that inhibits growth of many microbes
How does lysozymes contribute to innate defenses?
antimicrobial substance in perspiration, tears, saliva, nasal secretions and tissue fluids
How does gastric juice contribute to innate defenses?
destroys bacteria and most toxins in the stomach
How does vaginal secretions contribute to innate defenses?
slight acidity discourages bacterial growth; flush microbes out of vagina
