The Lymphatic System Flashcards
1
Q
Parts of lymphatic system
A
Lymphatic vessels
Lymphoid tissues and organs
2
Q
Functions of lymphatic system
A
- Transports escaped fluids from cardiovascular system back to blood
2.Body defense and resistance to disease
3
Q
Lymph is made of
A
Excess tissue fluid
Plasma proteins carried by lymphatic vessels
4
Q
What happens if excess fluids are not picked up?
A
Edema occurs as tissues accumulate in tissues
5
Q
Lymphatics
A
Lymphatic vessels
6
Q
What do lymphatics do?
A
Pick up and return excess fluid to blood
7
Q
Lymph in lymphatic vessels only flows toward
A
The heart
One way system
8
Q
Lymph capillaries location
A
Interwoven between tissue and blood capillaries
Connected by filaments
9
Q
Why do lymph capillaries have flap-like mini valves?
A
To let fluid leak in
10
Q
How do lymph capillaries work?
A
Higher pressure inside closes mini-valves
Fluid is forced along the vessel
11
Q
Function of lymphatic collecting vessels
A
1.Collect lymph from lymph capillaries
2.Carry lymph to and away from lymph nodes
- Return fluid to circulatory veins near the heart
12
Q
Right lymphatic duct function
A
Drains lymph from right arm and right side of the head and thorax
13
Q
Thoracic duct function
A
Drains lymph from rest of body
14
Q
Similarities between lymphatic vessels and veins of CV system
A
1.Thin walled
2.Larger vessels have valves
3. Low pressure pumpless system
15
Q
Lymph transport is aided by
A
- Milking action of skeletal muscles
- Pressure changes in thorax during breathing
- Smooth muscle in walls of lymphatics
16
Q
Function of lymph nodes
A
Filter lymph before it is returned to blood
17
Q
Harmful materials that lymph nodes filter
A
1.Bacteria
2. Viruses
3. Cancer cells
4. Cell debris
18
Q
Which defense cells are inside of the lymph nodes
A
Macrophages
Lymphocytes
19
Q
Lymphocytes in lymph
A
Respond to foreign substances
20
Q
Macrophages in lymph
A
Engulf and destroy bacteria, viruses and other foreign substances in lymph
21
Q
Appearance of lymph node
A
Kidney shaped
Less than one inch
Buried in connective tissue
Surrounded by capsule, separated in compartments by trabeculae
22
Q
Cortex (outer part of lymph nodes)
A
- Has follicles (collection of lymphocytes)
- Germinal centers enlarge when bodies are released by plasma cells
23
Q
Medulla (inner part of lymph nodes)
A
contains phagocytic macrophages
24
Q
Afferent lymphatic vessels
A
Carry lymph towards lymph node
25
Efferent lymphatic vessels
Carry lymph out of lymph nodes
26
Describe the flow of lymph through lymphatic vessels
1. Lymph enters convex side through afferent lymphatic vessels
2. Lymph flows through a number of sinuses inside of the node
3. Lymph exits through efferent lymphatic vessels
4. Because there are fewer efferent than afferent vessels, flow is slowed. (Slow flow helps screen for pathogens)
27
Other lymphoid organs
Spleen (curves around left side of stomach)
Thymus (In thorax)
Tonsils
Peyer's patches (in intestine)
Appendix
28
Spleen location
Left side of abdomen
29
Function of spleen
1. Cleans blood
2. Lymphocyte reproduction and immune surveillance
3. Destroys worn out blood cells
4.makes fetal blood cells
5. Acts as blood reservoir
30
Overlies the heart
Functions at peak levels only during youth. Decreases in size after growing
Thymus
31
Tonsils
Small masses of lymphoid tissues deep to mucosa surrounding pharynx (throat)
32
Tonsils function
1. Trap & remove bacteria/ pathogens
33
Cause of tonsillitis
Tonsils congested with bacteria
34
Peyer's patches location
Found in wall of small intestine
Similar lymphoid follicles are found in the appendix
35
Peyer's patches function
Macrophages capture and destroy bacteria in the intestine
36
Mucosa Associated Lymphoid tissues (MALT) include
Peyer's patches
Tonsils
Appendix
37
Acts as sentinel to protect respiratory and digestive tracts
MALT
38
Immunity
Specific resistance to disease
39
______ system is a functional system instead of organ system in anatomical sense
Immune system
40
Innate (nonspecific) defense mechanisms
1st & 2nd lines of defense
41
1st line of defense parts
1.Skin
2.Mucous membranes
3. Secretions of skin and mucous membranes
42
2nd line of defense parts
1.Phagocytic cells
2.Natural killer cells
3.Antimicrobial proteins
4.inflammatory response
5.Fever
6. Chemicals that kill pathogens
43
Adaptive (specific) defense mechanisms
Third line of defense
44
Third line of defense parts
1.Lymphocytes
2. Antibodies
3. Macrophages and other antigen presenting cells
45
Innate (nonspecific) defense system
1.Protect against variety of invaders
2.Responds immediately to protect body from foreign materials
46
Adaptive (specific) defense system
1. Fights invaders that get past the innate system
2.Specific defense is required for each type of invader
3. Highly specific resistance to disease is immunity
47
Natural killer cells
Promote cell lysis by direct cell attack against infected or cancerous cells
48
Inflammatory response
1.Prevents spread of harmful agents
2. Disposes pathogens and dead tissue cells
3.Promotes tissue repair
4. Attracts phagocytes
49
What do acidic skin secretions do?
Inhibit bacterial growth
50
How does sebum protect?
Sebum is toxic to bacteria
51
How does mucus protect
Mucus traps microorganisms
52
How do gastric juices protect
Acidic gastric juices kill pathogens
53
How do saliva and tears protect
Saliva and tears have lysozyme (enzyme that destroys bacteria)
54
Fever
High body temperature stops bacteria replication
Enhances body repair
55
Release chemicals called perforin and granzymes to degrade Target cell contents
NK natural killer cells
56
Triggered when body tissues are injured
Inflammatory response
57
Cardinal signs of acute inflammation
1. Redness
2. Heat
3.Pain
4. Swelling (edema)
58
Damaged cells release
Histamine
Kinin
59
Effects of histamine and kinin
1.Dilated blood vessels
2. Leaky capillaries
3.Phagocytes and white blood cells move into area (positive chemotaxis)
60
Process of inflammatory response
1. Neutrophils migrate to inflammation area by rolling along vessel wall (following scent of chemicals from inflammation)
2. Neutrophils squeeze through capillary walls by diapedesis to inflammation sites
3. Neutrophils gather in precise site of tissue injury (positive chemotaxis) and consume foreign material present
61
Neutrophils and macrophages engulf foreign material through
Phagocytosis
62
Phagocytes
Phagocytic vesicle is fused with lysosome,
Enzymes digest cell's contents
63
Steps of phagocytosis in a macrophage
1. Phagocyte adheres to pathogens
2.Phagocyte engulfs the particles, forming a phagosome
3. Lysosome fuses with phagocytic vesicle forming a phagolysosome
4.Lysosomal enzymes digest pathogens or debris, leaving a residual body
5. Exocytosis removes indigestible and residual material
64
Antimicrobial proteins enhance innate defenses by
Attacking microorganisms directly
Hindering reproduction of microorganisms
65
Most important types of antimicrobial proteins
Complement proteins
Interferon
66
Group of at least 20 plasma proteins that circulate in the plasma
Complement
67
Complement is activated when
Complement proteins encounter and attach to cells (complement fixation)
68
Membrane attack complexes (MACs) produce holes or pores in cells
Allow water to rush into cells
Cell bursts (lyses)
Complement proteins attach, make pore, let water in, cell bursts
69
Enhances inflammatory response
Activated complement
70
Interferons
Small proteins secreted by virus infected cells
71
Function of interferons
Bind to membrane receptors
Interfere with viruses multiplying ability
72
Hypothalamus regulates body temperature at
37 C
98.6 F
73
Hypothalamus thermostat can be reset by
Pyrogens (secreted white blood cells)
74
High temperatures inhibits the release of
Iron and zinc (needed by bacteria) from the liver and spleen.
75
Fever increases the speed of
Repair processes
76
Antibodies
Target and destroy antigens
77
Immune system's response to a threat
Immune response
78
Aspects of adaptive defense
1. Antigen specific
2. Systemic
3. Memory
79
Adaptive defense system recognizes and acts against particular foreign substances
Antigen specific
80
Immunity is not restricted to initial infection site
Systemic
81
Adaptive defense system recognizes and mounts a stronger attack on previously encountered pathogens
Memory
82
Two arms of adaptive defense system
Humoral immunity
Cellular immunity
83
Antibody mediated immunity
Humoral immunity
Provided by antibodies in body fluids
84
Targets virus infected cells, cancer cells and cells of foreign grafts
Cell-mediated immunity
85
Substances capable of exciting immune system and provoking immune response
Antigen
86
Foreign proteins
Nucleic acids
Large carbohydrates
Some lipids
Pollen grains
Microorganisms (bacteria, fungi, viruses)
Examples of non-self antigens
87
Presence of our cells in another person's body can trigger immune response because
They are foreign
88
What restricts donors for transplants
Self antigens
Our own antigens don't trigger response unless there is an autoimmune disorder
89
Haptens
Incomplete antigens
90
How do haptens work?
When they link up with our proteins, immune system may recognize the combination as foreign and attack
91
Haptens are found in
Poison ivy
Animal dander
Detergents
Hair dyes
Cosmetics
92
Produce antibodies and oversee humoral immunity. Respond to specific antigens
B lymphocytes (B cells)
93
Constitute cell-mediated arm of the adaptive defenses; do not make antibodies
T Lymphocytes (T cells)
94
Help the Lymphocytes, but don't respond to specific antigens
Antigen presenting cells (APCs)
95
Lymphocytes arise from
Hemocytoblasts of bone marrow
96
Whether a Lymphocyte matures into a B or T cells depends on
Where it becomes immunocompetent
97
Immunocompetence
Responding to a specific antigen because antigen binds to specific receptors on the Lymphocyte's surface
98
T cells develop immunocompetence in
Thymus
99
B cells develop immunocompetence in
The bone marrow
100
What happens to T cells that bind self antigens
They are destroyed,
Self tolerance is important part of Lymphocyte education
101
Immunocompetent T and B cells migrate to
Lymph nodes and spleen,
Here they encounter different antigens
102
Naive cells vs mature cells differentiation
Mature cells bind recognized antigens
103
Motion of mature Lymphocytes
Circulate continuously throughout the body
104
Engulf antigens and then present fragments of them on their own surfaces where they can be recognized by T cells
Antigen presenting cells APCs
105
Major types of cells behaving as APCs
Dendritic cells
Macrophages
B Lymphocytes
106
What happens when APCs present antigens
Dendritic cells and macrophages activate T cells, which release chemicals
107
What triggers clonal selection
Binding between B Lymphocyte and a specific antigen
108
Clonal selection (primary humoral response)
Large number of clones produced
109
Descendants
B cell clone members
110
Most of the B cell clone members become
Plasma cells
111
Plasma cells
Produce antibodies to destroy antigens
Activity lasts 4-5 days
Plasma cells begin to die
112
Some B cells become long lived memory cells meaning
Capable of mounting rapid attack against the same antigen in subsequent meetings (secondary humoral response)
113
Secondary humoral response
B cells become long lived memory cells
114
Active immunity
B cells encounter antigens and produce antibodies
115
How can you acquire active immunity
Naturally through infections
Artificially through vaccines
116
Passive immunity
Get antibodies from someone else
Breast milk
Immune serum
Gamma globulin (donated antibodies)
117
Short lived protection
2-3 weeks
Immunological memory doesn't occur
118
Monoclonal antibodies
Prepared for clinical for diagnostic services
Produced from descendants
Exhibit specificity from one antigen
119
Examples of uses for monoclonal antibodies
Cancer treatment
Diagnosis of pregnancy
Treatment after exposure to hepatitis and rabies
120
Gamma globulin part of blood proteins
Antibodies
121
Immunoglobulins, Igs
Antibodies
122
What is the structure of antibodies
1. 4 polypeptides ( 2 heavy and 2 light) linked by disulfide bonds to form T or Y
123
Variable regions
Form antigen binding sites, one on each arm of the T or Y
124
Constant regions
Determine type of antibody formed (antibody class)
125
Each polypeptide chain has 2 regions
Variable region
Constant region
126
Antibody classes
Antibodies of each class have slightly different roles and differ structurally and functionally
127
Five major immunoglobulin classes
M
A
D
G
E
128
IgM
Can fix complement
129
IgA
Found mainly in secretions, such as mucus and tears
130
IgD
Helps activate B cells
131
IgG
Cross placental barrier and fix complement; most abundant antibody in plasma
132
IgE
Involved in allergies
133
Chief antibody ammunition used against cellular antigens
Complement fixation
134
Neutralization
Antibodies bind to specific sites on bacterial exotoxins or on viruses that can cause cell injury
135
Precipitation
Cross-linking reaction in which antigen antibody complex settles out of solution
136
Main difference between B and T cells
B cells secrete antibodies
T cells fight antigens directly
137
Like B cells, immunocompetent T cells are activated to
form a clone by binding with a recognized antigen
138
Unable to bind to free antigens
T cells
139
Antigens must be presented by a
Macrophage, and double recognition must occur
140
APC engulfs and presents the processed antigen in combination with
A protein from the APC
141
Antigen presentation
Cells must recognize non-self and self
142
Non-self
Antigen fragment presented by APC
143
Self
Coupling with a specific glycoprotein on the APCs surface at the same time
144
Helper T cells
Recognize foreign antigens
Secrete cytokines (activate T & B cells)
145
Cytotoxic T cells
Kill cancerous, infected and damaged cells
146
Cytotoxic ( killer) T cells
Insert toxic chemicals (perforin or granzyme)
147
How do killer T (cytotoxic cells work?)
1.T cell attaches and inserts a toxic chemical like perforin or granzyme
2.Perforin & granzyme enters foreign cell's plasma membrane
3.perforin makes pores.Pores now appear in target cell's membrane
4.Granzymes (protein digesting enzymes) enter and kill the foreign cell
5. Cytotoxic T cell detaches and seeks other targets
148
Perforin
Causes cell lysis
149
Granzymes
Protein digesting enzymes
150
Which cells recruit other cells to fight invaders?
Helper T cells
151
Directly interact with B cells bound to an antigen , prodding the B cells into clone production
Helper T cells
152
Cytokines
Chemicals that act directly to rid the body of antigens
153
Regulatory T cells
Release chemicals to suppress the activity of T & B cells
Stop immune response to prevent uncontrolled activity
Few members of each clone are memory cells
154
Tumor necrosis factor
Causes cell killing, attracts granulocytes; activates T cells and macrophages
155
Complement
Activate after binding to antibody covered antigens, when active, complement causes lysis of microorganism and enhanced inflammatory response
156
What percent of blood group and tissue must match to attempt a graft?
75%
157
Immunosuppressive therapy
Therapy after transplant. Helps prevent rejection
158
Most important disorders of the immune system
1. Allergies
2. Autoimmune diseases
3.Immunodeficiencies
159
Hypersensitivities,
Abnormal, vigorous immune responses. Immune system overreacts to a harmless antigen
Allergies, tissue damage occurs
160
Immediate (acute allergies) cause
IgE antibodies and histamine
161
Hives and anaphylaxis are symptoms of
Immediate acute hypersensitivity
162
What kind of allergy is anaphylactic shock (Systemic)?
Acute allergic response
163
Delayed hypersensitivity
Reflects activity of T cells, macrophages, cytokines
164
Symptoms appear 1-3 days after coming in contact with the antigen
Delayed hypersensitivity
165
Allergic contact dermatitis (poison ivy, cosmetics) is caused by
Delayed hypersensitivity
166
Allergy mechanism
1. Antigen invades body
2.Plasma cells produce large amounts of class IgE antibodies against allergen
3.IgE antibodies attach to mast cells in body tissues (and to circulating basophils).
4.More of same allergen invades body
5.Allergen binding to IgE on mast cells triggers release of histamine and other chemicals
6. Histamine causes blood vessels to dilate and become leaky, which promotes edema, large amounts of mucus, smooth muscles contract
167
Autoimmune diseases occur when
Occurs when body's self tolerance breaks down
168
Body produces auto antibodies and sensitized T lymphocytes that attack its own tissues
Auto immune diseases
169
The body produces autoantibodies and sensitized lymphocytes that attack its own tissues
Autoimmune diseases
170
Body produces Auto antibodies and sensitized T lymphocytes that attack its own tissues
Autoimmune disease
171
Most autoimmune diseases result from
1.Formerly hidden self antigens
2. Changes in structure of self antigens
3.antibodies formed against foreign antigens that resemble self antigens
172
Rheumatoid arthritis
Myasthenia gravis
Multiple sclerosis
Graves disease
Autoimmune disorder examples
173
Rheumatoid arthritis
Destroys joints
174
Myasthenia gravis
Impairs communication between nerves and skeletal muscles
175
Multiple sclerosis
White matter of brain and spinal cord is destroyed
176
Graves disease
Thyroid gland produces excess thyroxine
177
Destroys pancreatic beta cells, deficient insulin production
Type I diabetes mellitus
178
Systemic Lupus erythematous (SLE)
Affects kidney, heart, lungs and skin
179
Glomerulonephritis
Severe impairment of kidney function due to acute inflammation
180
Types of immunodeficiencies
Congenital or acquired
181
SCID severe combined immunodeficiency disease is a type of
Congenital disease
Can be present at birth, children have very little immune function
182
AIDS (acquired immune deficiency syndrome,) is caused by
Virus that attacks and cripples helper T cells
183
Immunodeficiencies result from
Abnormalities in any immune element
184
Production or function of immune cells or complement is
Abnormal
185
Proteins secreted by activated B cells
Antibodies
186
Formed in response to large number of antigens
Antibodies
