1
Q
Anatomy
A
The lymphatic system is part of the circulatory system Functions very different from the heart & blood vessels Consists of: Lymph & lymph vessels Lymphatic tissue lymph nodes & nodules Spleen Thymus Lymphocytes
2
Q
The lymphatic system is part of the ___ system.
A
circulatory system
3
Q
Purpose of the Lymphatic System
A
- Protect the body against foreign material
- Responsible for returning tissue fluid to the blood
- Maintain blood volume which maintains blood pressure
4
Q
Define Lymph
A
- the water found within lymphatic vessels
- tissue fluid that enters the lymph capillaries
5
Q
Capillaries create ____ from blood plasma which (most of it) ____ to the blood in capillaries by the process of _____
A
tissue fluid, returns, osmosis
6
Q
Some lymph remains in the
A
interstitial spaces
7
Q
Lymph is returned to the blood by way of
A
the lymphatic vessels
8
Q
Lymph helps to maintain
A
blood volume & blood pressure
9
Q
Lymph vessels
A
- The system begins as “dead-end” lymph capillaries in the tissue spaces
- Very permeable & collect fluid & proteins
10
Q
Capillaries unite to
A
form larger lymph vessels
11
Q
What does Lymph not have
A
NO PUMP
12
Q
Lymph returns to the blood to
A
to become plasma again
13
Q
Lymph vessels keep lymph moving with (3)
A
- smooth muscle contraction; skeletal muscle pump
- one way valves (to prevent backflow)
- respiratory pump
14
Q
Cisterna chyli
A
- a large lymph vessel formed by the union of lymph vessels from the lower body
- continues superiorly as the thoracic duct
15
Q
Lymph from the lower body & upper Lt quadrant enter the thoracic duct & is returned
A
to the blood in the Lt subclavian vein
16
Q
Lymph from the upper Rt quadrant enter the Rt lymphatic duct & is returned
A
to the blood in the Rt subclavian vein
17
Q
LYMPHATIC TISSUE
A
A hemopoietic tissue that produces some lymphocytes
18
Q
Lymphatic tissue is found in
A
- the spleen
- thymus
- nodes
- nodules
19
Q
Lymphocytes - (WBC)
A
- produced from stem cells in red bone marrow
- migrate to the lymph nodes, nodules, spleen, & the thymus
20
Q
Lymphocytes become activated & proliferate in response
A
to infection ( a function of all lymphatic tissue)
21
Q
Lymph node
A
a small mass of lymphatic tissue located along the pathway of lymphatic vessels
22
Q
Lymph node produces
A
lymphocytes & destroys pathogens in the lymph
23
Q
Approximate length of lymph nodes
A
Usually 10 – 20 mm long
24
Q
Lymph enters ____ vessels & leaves by ____ vessels
A
afferent, efferent
25
Pathogens are phagocytized
by macrophages
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Plasma cells develop from
from the lymphocytes exposed to the pathogen & produce antibodies
27
Lymph nodes- Major paired groups (3)
1) Cervical
2) Axillary
3) Inguinal
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Cervical
junction of the head & trunk
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Axillary
junction of the trunk & upper extremities
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Inguinal
junction of the trunk & lower extremities
31
LYMPH NODULE
a small mass of lymphatic tissue found just below the epithelium of all mucous membranes
32
mucous membranes
- urinary
- digestive (Peyer’s patches)
- respiratory (tonsils)
- reproductive tracts
33
lymph nodules destroy pathogens that
penetrate mucous membranes
34
Lymph nodule length
usually a fraction of a mm to several mm’s long
35
example of redundant structure
tonsils
36
Spleen is located in the
upper left quadrant of the abdominal cavity
37
Spleen is below the
diaphragm
38
Spleen is behind the
stomach
39
Spleen is protected by
the lower ribcage
40
Spleen function in the fetus
- produces RBC
| - after birth RBC’s are produced by red bone marrow
41
Spleen contains
- plasma cells
- macrophages
- Stores platelets
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Plasma cells produce
antibodies
43
Macrophages phagocytize
pathogens & RBC’s (forms bilirubin)
44
Spleen destroys
platelets when they are no longer useful
45
Thymus
- Located inferior to the thyroid gland
| - In the fetus & infant , the thymus is large & extends under the sternum
46
With age the thymus
shrinks
47
Thymus produces
- T lymphocytes (T cells)
| - thymic hormones
48
Thymic hormones
- enable the T cells to recognize foreign antigens
| - provide immunity
49
Define Immunity
-the ability to destroy foreign antigens & prevent future cases of certain infectious diseases
50
Define Antigens
chemical markers that identify cells; self and foreign
51
Self antigens
chemical markers that identify human cells as self
52
Foreign (non-self) antigens
stimulate immune responses
53
Innate immunity – nonspecific response
- Does not create memory cells
| - Does not become more efficient
54
Innate immunity consists of
- Barriers
- Defensive cells
- Chemical defenses
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Adaptive Immunity
- Response specific for a foreign antigen
- Creates memory
- Becomes more efficient
56
Adaptive Immunity is carried out by
T cells (lymphocytes), B cells (lymphocytes) & macrophages
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Adaptive Immunity recognizes
antigen as foreign
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Adaptive Immunity initiates
immune mechanisms
59
Immune mechanisms (adaptive immunity)
- Cell-mediated immunity
| - Antibody-mediated immunity
60
Cell-mediated Immunity
- does not involve antibodies
| - Effective against intracellular pathogens such as viruses, fungi, malignant cells & grafts of foreign tissue
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Helper T cells
recognize the foreign antigen & begin to divide
62
Memory T cells
remember the specific antigen
63
Cytotoxic T cells destroy
the cells
64
Cytotoxic T cells produce
cytokine to attract macrophages
65
Antibody Mediated Immunity (humoral immunity)
- involves antibody production
| - Becomes more efficient with repeated exposure to pathogens & foreign cells
66
B cells & helper T cells recognize
the antigen
67
B cells are antigen specific & begin to
divide
68
B cells become plasma cells & produce
antigens specific antibodies
69
An antigen
antibody complex is formed & attracts macrophages (opsonization)
70
Complement proteins
bind to the complex & destroy the antigen
71
Antibody
-gamma globulin, immune globulin
-a protein molecule produced by plasma cells
specific for & will bond to
-a specific foreign antigen.
72
What do antibodies do to antigens
- DO NOT destroy antigens
- attach to antigens-antibody complex
- label them for destruction
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What does antigen-antibody complex stimulate
the process of complement fixation
74
ANTIBODY RESPONSE
- 1st exposure
- 2nd exposure
- Antibodies cause agglutination
- Antibodies neutralize viruses
- Antibodies neutralize bacterial toxins
75
1st exposure
a small amt of antibodies is produced slowly (person may develop disease)
76
2nd exposure
memory cell produce a large amt of antibodies, quickly ( person does not develop disease)
77
Antibodies cause agglutination of bacterial cells which are then destroyed
by the macrophages
78
Antibodies neutralize viruses by
bonding & preventing them from entering the cell
79
Antibodies neutralize bacterial toxins by
bonding & changing their shape
80
Immunity
the state of being protected from an infectious disease
81
TYPES of IMMUNITY: (2) major categories
1) Genetic immunity
| 2) Acquired immunity
82
Genetic immunity
conferred by DNA; does not involve antibodies; lasts a lifetime
83
Acquired immunity
developed or acquired by natural or artificial means; involves antibodies
84
Active immunity
individual produces antibodies
85
Passive immunity
antibodies are acquired from another source; protection is always temporary
86
AFFECTS of AGING
- Decreased efficiency of the immune response
- More susceptible to infections & secondary infections
- Autoimmune disorders more prevalent
- Incidence of cancer is higher
87
Autoimmune disorders
- Rheumatoid arthritis
| - Myasthenia gravis
88
Incidence of cancer is higher because of aging
Malignant cells are not as easily destroyed & therefore remain alive & proliferate
