Lecture Test 3 Part 2 Flashcards
1
Q
What is the thoracic duct?
A
larger duct that drains lymph from the left side of the head, left chest, left upper arm, and the entire body below the diaphragm.
2
Q
Where does the thoracic duct drain into?
A
left subclavian vein
3
Q
Unlike the cardiovascular system, the lymphatic system is
A
pumpless
4
Q
What helps lymph flow in lymphatic vessels?
A
valves
milking by skeletal muscles
breathing
5
Q
How does lymph flow differ from blood flow?
A
lymph flow is slower and spoadic
6
Q
How much lymph enters the lymphatic vessels per day?
A
3L
7
Q
What is the effect of blocking the drainage of interstitial fluid in the lymphatic system?
A
lymphedema (swelling)
8
Q
What is lymphoid tissue?
A
houses lymphocytes
9
Q
What type of tissue is lymphoid tissue?
A
reticular connective tissue made of reticular fibers
10
Q
what are reticular fibers?
A
very fine collagen fibers
11
Q
What are lymphoid organs?
A
red bone marrow nodes spleen thymus tonsils
12
Q
what are the smaller lymphoid structures?
A
appendix
peyer’s patch
13
Q
what is red bone marrow?
A
responsible for production of lymphocytes and macrophages
14
Q
where is red bone marrow found?
A
inside SOME bones
15
Q
what occurs in red bone marrow?
A
hemapoiesis
16
Q
what is the lymph node?
A
encapsulated oval structures located alond lymphatic vessels
17
Q
Where can large congregations of lymph nodes be found?
A
inguinal, cervical and axillary regions
18
Q
What are the 2 major functions of lymph nodes?
A
filtration
activating the immune system
19
Q
How do the lymph nodes filter lymph?
A
macrophages and lymphocytes destroy microorganisms that enter from the lymph and prevent them from entering blood and spreading to the rest of the body.
20
Q
What are the lymph nodes role in activating the immune system?
A
they contain germination centers for lymphocytes and monocytes
21
Q
Lymph nodes are the only organ that
A
filters lymph
22
Q
what is a lymphadenopathy?
A
enlargement of the lymph nodes with no pain. Usually implies cancer
23
Q
What is a lymphadenitis?
A
enlargement of the lymph nodes with pain usually due to infection
24
Q
What is the anatomy of the spleen?
A
size of a fist
soft and rich in blood
under the diaphragm, on the left side
25
The spleen provides a site for
immune functions
| blood production in the fetus
26
what is the spleen's main function?
to remove old and dying RBCs and be a blood reservoir
27
The spleen's capsule is
thin and can easily rupture due to trauma
28
When a spleen's capsule ruptures....
the spleen must quickly be removed and the splenic artery must be tied off to prevent hemorrhaging
29
What is the removal of the spleen called?
spleenectomy
30
After a spleenectomy has occurred, who takes over the function of the spleen?
liver and red bone marrow
31
what is the location of the thymus?
anterior and superior to the heart
32
what hormone does the thymus secrete?
thymosin
33
what is the function of thymosin?
matures t cells
34
How big is the thymus?
increases in size until the first birthday then stays the same size until age 60
35
What happens to the thymus at age 60?
it becomes smaller and much of its functional tissue is replaced by fibrous connective tissue
36
what are the tonsils?
MALT
37
what is MALT?
mucosa associated lymphatic tissue
38
what are the three groups of tonsils?
palatine tonsils
lingual tonsils
pharangeal tonsils
39
what are palatine tonsils?
largest of the tonsils and most easily infected
40
where are the palatine tonsils located?
either side of the posterior cavity
41
what happens to palatine tonsils in adults?
they decrease in size
42
what are lingual tonsils?
found at the base of the tongue
43
what are pharyngeal tonsils?
posterior wall of the nasopharynx
44
pharyngeal tonsils are also called
adenoids
45
what is the peyers patch?
clusters of lymphoid tissue containing lymphoid cells that offer immune protection to the ileum
46
what is the appendix?
tubular offshoot of the cecum composed of lymphatic tissue and cells
47
what is Hodgkin's disease?
form of cancer that arises in the lymph nodes
48
what are the symptoms of Hodgkin's?
```
painless swelling of the lymph nodes (usually in the neck)
night sweats
fever
fatigue
weight loss
```
49
what is the treatment for Hodgkin's?
radiation
chemotherapy
bone marrow transplants
50
Hodgkin's disease is considered
curable
51
What are the two defense systems?
```
innate immunity (nonspecific defense)
adaptive immunity (specific defense)
```
52
what is innate immunity (nonspecific)?
group of protective mechanisms that respond immediately to protect the body from ALL foreign invaders.
53
What is adaptive immunity (specific)?
group of protective mechanisms that mounts its attack against a specific invader.
54
The cells that attack during an adaptive immunity attack are
are specific for that foreign substance and have memory
55
Innate and adaptive immunity occur
at the same time and work together to protect the body
56
what are pathogens?
harmful or disease causing organisms
57
what are the seven tools of the innate immunity system?
```
species resistance
mechanical barriers
chemical mediators
natural killer cells
phagocytes
inflammation
fever
```
58
what is species resistance?
a given species is susceptible to diseases that may be unique to that species and to no other.
59
what types of infections can cross species?
zoonotic infection
60
what is a type of zoonotic infection?
rabies
61
what are mechanical barriers?
the body's first line of defense
62
what are some examples of mechanical barriers?
skin that is unbroken
tears
saliva
63
Mucous membranes are a type of mechanical barrier because
they secrete substances that can kill invaders
64
what is a lysozyme?
an enzyme that destroys bacteria
65
what is an example of a lysozyme?
tears
saliva
HCL
66
what are two types of chemical mediators?
interferon
| complement
67
what is interferon?
substance produced by cells toxic to viruses
68
interferon is
nonspecific so it protects against a number of viruses
69
How does interferon work?
protects neighboring cells
70
what is complement?
group of at least 20 plasma proteins that normally circulate in the blood in an inactive state. When stimulated they complement the functioning of innate and adaptive immune systems
71
what are some examples of complement?
membrane attack complex
chemotaxic agents
histamines
opsonization
72
what is membrane attack complex?
punches holes in cell walls
73
what are chemotaxic agents?
attract WBCs to the area
74
How are histamines a complement activity?
complement stimulates the release of histamines from basophils and platelets as a result of trauma. This increases the permeability of blood vessels in the injured area
75
what is opsonization?
improving phagocytes ability to adhere to the pathogen
76
what are natural killer cells?
unique white blood cells that "police" the body in the blood and the lymph
77
natural killer cells have the ability to
find and lyse some cancer and virus affected cells before the immune system is activated
78
How do natural killer cells work?
not by phagocytosis but by attaching themselves to their target and destroying its cell membrane
79
what do natural killer cells secrete?
perforins
80
what are phagocytes?
cells that eat organisms
81
what are the chief phagocytes?
macrophages
82
where do macrophages derive from?
circulating monocytes that leave the blood stream and enter through the tissues and enlarge
83
what are wondering macrophages?
macrophages that constantly wander through the interstitial spaces looking for invaders
84
what are fixed macrophages?
macrophages that remain within certain organs
85
what is an example of a fixed macrophage?
kupffer cells in the liver
86
what is another type of phagocyte?
neutrophils
87
eosinophils are
slightly phagocytic
88
what sometimes prevents phagocytes from being successful?
inability to adhere to the invader
89
how is inflammation a part of innate immunity?
prevents the spread of damaging agents
disposes of debris and pathogens
sets the stage for repair
90
what are the four signs of inflammation?
```
redness
heat
swelling
pain
(sometimes a loss of function in serious injury)
```
91
_________ leads to a release of various chemicals
tissue injury
92
the release of certain chemicals after inflammation causes
```
dilation of blood vessels
increase permability of blood vessels
swelling
pain
chemotaxis of WBCs
```
93
the dilation of blood vessels causes
more blood to go to the area of the injury causing redness and heat
94
increased permeability of the capillaries causes
emigration
95
swelling is
increased amount of blood in the vessels leads to an increase in pressure within the capillaries resulting in more fluid escaping into the interstitial spaces
96
pain is caused when
swelling puts an increase of pressure on the nerves
97
chemotaxis of WBCs is due to
leukocytosis
98
what is leukocytosis?
injured cells stimulate rapid release of neutrophils
99
Within one hour after inflammation, neutrophils
have collected at the site of injury and are eating the invader
100
Following neutrophils, ________ are second responders
monocytes
101
monocytes swell and
increase the number of lysosomesin the cytoplasm to become macrophages.
102
Macrophages are responsible for
the final clean up of the infected area and the dead neutrophils
103
What happens to severe infections?
pus accumulates
104
what is pus?
a mixture of dead neutrophils, broken down tissue cells, pathogens and macrophages
105
What is an absess?
When pus accumulates under the skin.
106
Fever is a
systemic protective mechanism against a pathogen
107
Body temperature is regulated by
the hypothalamus
108
Normal body temperature is
99.7 degrees
109
What are pyrogens?
a secretion of lymphocytes, neutrophils and macrophages as they attack pathogens
110
Pyrogens stimulate the release of
prostaglandins which raises the set thermostat
111
When a person has chills during a fever it indicates
that the fever is rising.
112
Why do you have chills during a fever?
the muscles are contracting to produce more heat in order to reach the new temperature setting in the hypothalamus.
113
When a person sweats during a fever
it indicates that the fever is dropping
114
Mild fevers are beneficial because
there is an increase in metabolic rate of tissue cells speeding up defensive actions and repair processes
115
High fevers can be dangerous because
they can inactivate enzymes leading to tissue damage and death
116
How does aspirin work?
prevents temperature from rising.
117
Aspirin is an
antiprostaglandin that makes you feel better
118
What are antigens?
substances that stimulate an adaptive immunity
119
Antigens can be classified as
foreign antigens or self antigens
120
What are foreign antigens?
antigens not produced by the body but introduced from the outside
121
What are some examples of foreign antigens?
bacteria
viruses
parasites
transplanted tissue
122
what are self antigens?
molecules produced by the body that stimulate an adaptive immune response
123
What are some examples of self antigens?
autoimmune diseases
124
Adaptive immunity results from the activities of
T cells and B cells ( a type of lymphocyte)
125
T cells and B cells have been programmed at birth to
respond to specific antigens
126
In a lifetime, T and B cells
will never be challenged
127
In order for an adaptive immunity response to occur
lymphocytes must recognize the specific antigen and after recognition, the lymphocytes must increase in number to effectively destroy the antigen
128
As T and B cells are produced, they develop
receptors that are programmed to recognize different epitopes that they may come in contact with during the person's life time
129
What is an epitope?
specific regions of a given antigen that will be recognized by specific populations of T and B cells
130
Some antigens bind to
their receptors and directly activate B and T cells
131
Most lymphocyte recognition involves
major histocompatibility complexes
132
what are major histocompatibility complexes?
glycoproteins that are unique to an individual (except identical twins) that are found on all cell membranes except red blood cells
133
Once recognition occurs, the specific lymphocyte
goes through cell division increasing the number of cells equipped to destroy the antigen.
134
Where does cell division occur?
lymphatic tissue
135
Many times ____________ are necessary in recognition between antigen and its specific cells.
antigen presenting cells
136
What is an example of an antigen presenting cell?
macrophages
137
How do macrophages function?
They first phagocytize the antigen. The partially digested antigen is then displayed on the surface of the macrophage and then presented to the T and B cells for recognition.
138
Recognition between the specific antigen and its T and B lymphocytes also needs ____________ with cytokines and other cells called helper T cells
costimulation
139
what are helper T cells?
cells that proliferate first when meeting an antigen through the secretion of interleukin 2. The specific T/B cells increase and will directly be responsible for destroying the antigen by proliferation of these specific lymphocytes into identical cells called a clone
140
what is a clone?
a population of identical cells
141
T cells develop from
hemocytoblasts in the red bone marrow
142
T cells then migrate to the ________ to mature
thymus gland
143
In the thymus T cells develop
immunocompetence
144
Immunocompetence:
the ability to carry out immune responses if properly stimulated
145
Most T cells arise before
puberty but some continue to develop throughout its life
146
T cells develop ________ on the cell membrane that can recognize specific antigens that the body may be challenged with in life
antigen receptors
147
T cells are very effective against
```
fungi
parasites
viruses
cancer cells
foreign tissue transplants
```
148
Mature T cells will leave the thymus gland and
become embedded in lymphoid tissue or will freely circulate
149
What are the different subpopulations of T cells that are vital in response
helper T cells
Cytotoxic T cells
Memory T cells
suppressor t cells
150
what are helper t cells?
cells that do not directly attack the antigen but produce cytokines mainly interleukin 2
151
what are cytokines
small hormones that are involved with cell functions
152
interleukin 2 is needed for
all adaptive immune responses.
153
Without helper t cells
the adaptive immune system is nonfunctional
154
what are cytotoxic t cells
cells that are directly responsible for destroying the invader always requiring costimulation by helper T cells.
155
After being activated and proliferating in the lymphoid tissues, cytotoxic t cells
migrate to the site of invasion and produce perforins and lymphotoxins that will destroy the specific invader
156
what are memory t cells?
cells that are programmed to destroy a recurring invader (chicken pox)
157
The secondary reaction of memory t cells will be
much faster and the person may not ever know that they've come in contact with the antigen again.
158
What are suppressor t cells?
poorly understood, probably associated with tolerance/autoimmune disease
159
When B cells are activated they will produce
antibodies that kill the specific antigen
160
B cells are formed from
hemocytoblasts in red bone marrow
161
b cells mature in
red bone marrow and gain immunocomptency
162
After b cells gain immunocompetency,
they leave the RBM and establish residency within a lymphoid tissue or circulate
163
After recognition of specific antigens occurs
proliferation follows
164
During proliferation
B cells enlarge, divide and differentiate into plasma cells
165
Plasma cells produce
antibodies
166
The B cells that don't become plasma cells
form memory cells
167
Plasma cells produce
2,000 molecules of antibodies per second for 4-5 days
168
What is an antibody?
protein produced in response to an antigen
169
The antibodies produced by the clone of plasma cells
enter circulation and form Antigen-antibody complexes with the specific antigen.
170
What are the different ways an antibodies destroy antigens?
immobilization
agglutination and precipitation of antigen
activation of complement
initiation of inflammatory response
171
What is immobilization:
antibodies form against the cilia or flagella of some bacteria and these bacteria lose their mobility
172
what is agglutination and precipitation of antigen?
the antibodies may cause the antigens to clump together. Phagocytosis is easier
173
What is activation of complement?
antigen-antibody complexes initiate complement activation
174
What are the 5 different classes of antibodies that plasma cells produce?
```
IgG
IgA
IgM
IgD
IgE
```
175
IgG is
most abundant 80% of all antibodies in the body
176
IgA:
15% of antibodies
177
IgM:
5-10% of antibodies
178
IgD:
Less than 1% of antibodies
179
IgE:
less than 1% of antibodies. Involved with allergic reactions
180
What are B memory cells?
cells that quickly recognize the antigen during a later exposure and kill it before the body reacts to it.
181
The secondary respose of B cells:
is much quicker and stronger than the primary response
182
What is lag time?
time between the invasion of antigen into body and the appearance of antibodies
183
Why is there a lag time?
due to the time needed for the specific B cells to divide and differentiate into plasma cells
184
what are autoimmune diseases?
the immune system fails to recognize itself and lanches an immune attack against its own system
185
What are some examples of autoimmune disease?
rheumatoid arthritis, diabetes mellitus, multiple sclerosis and lupus
186
What causes autoimmune inflammatory disease of connective tissue?
unknown but occurs in families
187
who is mostly affected by autoimmune disease of connective tissue?
women
188
what are the symptoms of autoimmune disease of connective tissue?
pain in joints
photosensitivity
rash across the eyes and nose
inflammation of kidneys, liver, spleen, heart and central nervous system
189
what is an allergic reaction?
an over reaction to an antigen that is tolerated by most others
190
the antigen that causes an allergic reaction is called an
allergen
191
what are some common allergens?
```
milk
nuts
some drugs
vaccines
some plants
venoms
```
192
what is the outcome of allergic reactions?
varies from a congested nose to anaphylaxis
193
what is anaphylaxis?
severe reaction with an allergen that results in mass vasodilation, increased permeability (leading to swelling), increased smooth muscle contraction the airways of the lungs and increased mucus production
194
what is tissue rejection?
When the body recognizes transplant tissues as nonself and mounts an immune response.
195
The more similar the surface proteins are between donor and recipient,
the weaker the rejection response.
196
What is the drug used in transplants to decrease tissue rejection?
cyclosporine
197
What is cancer?
when a normal cell transfers into a cancer cell it displays tumor antigens.
198
If the immune system can detect cancer cells as nonself,
they can be destroyed.
199
What is immunological surveillance?
there are cells that are constantly circulating and guarding against the appearance of cancer cells.
200
What happens to immunological surveillance as we age?
it decreases and cancer risk increases.
201
What is AIDS?
an immunological disease identified in the 1980s cause by human immunodeficiency virus
202
How was AIDS first identified?
CDC in Atlanta had high rates of pneumocytosis pnemonia
203
what causes pnemocytosis pneumonia?
a protozoan and a Kaposi's sarcoma.
204
What is a Karposi's sarcoma?
cancer of the blood vessels seen as purple lesions on the skin
205
Who is mostly affected by Karposi's sarcoma?
elderly homosexual men
206
HIV cannot
live long outside its host
207
HIV is transmitted by
body secretions such as blood, semen, vaginal secretions, tears and saliva
208
What types of cells can HIV enter?
helper t cells
macrophages
brain cells
209
When helper T cells are invaded by HIV
the population is decreased and the immune system colapses
210
How do patients usually die from AIDS?
opportunistic diseases such as cancer, pneumonia, or a raging infection
211
When do symptoms of HIV occur
a few months to ten years after diagnosis
212
What are nonprogresssors?
people who have been infected by HIV but after 10-15 years show no symptoms of it
213
HIV is a
retrovirus
214
what is a retrovirus?>
its genetic code is found on RNA not DNA
215
The core of HIV contains
RNA and reverse transciptase
216
What surrounds the core of a HIV cell?
protein coat or capsid
217
The enter HIV cell is surrounded by
a lipid bilayer with glycoproteins
218
what is the function of the glycoproteins
help the HIV to bind and enter target cells
219
How does the virus enter the host cell?
reverse transcriptase produces viral DNA from RNA. THe DNA inserts itself into the hosts DNA and directs it to produce new viruses.
220
HIV has a high
mutation rate changing its coat rapidly and making the development of a vaccine hard
221
What is the treatment for HIV/AIDS?
combination therapy of AZT and protease
222
What does AZT do?
it is a reverse transciptinase inhibitor
223
what does protease do?
prohibits the manufacturing of the protein coat on new viruses
