Test 6 Hematology, Lymphatic and Immune Flashcards
1
Q
What are three (3) major functions of blood?
A
- Transport
- Regulation
- Protection
2
Q
Describe three (3) characteristics of blood’s function of TRANSPORT
A
- Delivery of necessary gases & nutrients
- Transport wastes to excretion sites
- Transport hormones to target organs
3
Q
Describe three (3) characteristics of blood’s function of REGULATION
A
- Maintain body temperature
- Maintain normal pH (acts as buffer)
- Maintain adequate fluid volume (water)
4
Q
Describe two (2) characteristics of blood’s function of PROTECTION
A
- Prevent blood loss – clots
2. Prevent infection – antibodies & WBC (immune)
5
Q
What is extracellular fluid?
A
All fluid in the body found OUTSIDE of cells.
6
Q
What is intracellular fluid?
A
All fluid in the body found INSIDE of cells.
7
Q
What is interstitial fluid?
A
Extracellular fluid found BETWEEN cells (interstitial spaces).
8
Q
What are seven (7) components of blood plasma?
A
- Water (90%)
- Proteins
- Metabolic waste products
- Electrolytes
- Nutrients
- Respiratory gases
- Drugs
9
Q
What are four (4) main types of proteins found in blood plasma?
A
- Albumin (60%)
- Globulins
- Clotting proteins
- Enzymes/Hormones
10
Q
Describe the shape and composition of erythrocytes
A
Biconcave disc containing no organelles or nucleus. Composed of approximately 97% hemoglobin.
11
Q
Describe the size of erythrocytes
A
Approximately 5 million RBCs per cubic millimeter.
12
Q
How long is the life span of an erythrocyte?
A
100-120 days.
13
Q
What are the five (5) leukocyte classifications, in order from most abundant to least abundant?
A
- Neutrophils
- Lymphocytes
- Monocytes
- Eosinophils
- Basophils
14
Q
What are the three (3) granulocytes?
A
- Neutrophils
- Eosinophils
- Basophils
15
Q
What are the two (2) agranulocytes?
A
- Lymphocytes
2. Monocytes
16
Q
Describe the structure and function (3) of a neutrophil
A
- Multilobed nucleus
- cytoplasmic granules
- first response phagocyte
17
Q
Describe the structure and function (3) of an eosinophil
A
- Bilobed nucleus
- red cytoplasmic granules
- phagocyte
18
Q
Describe the structure and function (3) of a basophil
A
- Dark multilobed nucleus
- Dark purplish-black cytoplasmic granules
- Releases histamine
19
Q
Describe the structure and function (3) of a lymphocyte
A
- Round nucleus
- No visible cytoplasmic granules
- T cells and B cells
20
Q
Describe the structure and function of a monocyte
A
- Kidney shaped nucleus
- No visible cytoplasmic granules
- Active phagocytes
21
Q
What is a monocyte called when it leaves the blood stream and enters tissue?
A
Macrophage
22
Q
What phagocyte specializes in reacting to parasites and allergens?
A
Eosinophil
23
Q
What are the two (2) functions of histomine when released by Basophils?
A
- Causes vasodilation/inflammation
2. Attracts leukocytes
24
Q
What pathogens do neutrophils specialize in killing?
A
bacteria
25
What is the term used for the production of white blood cells?
Leukopoiesis
26
What is the name of the "uncommitted" stem cell that will eventually become a blood cell?
Hemocytoblast
27
What is the name of the stem cell that will eventually become a monocyte, granulocyte or erythrocyte?
Myeloid stem cell
28
What is the name of the committed stem cell that will eventually become a lymphocyte?
Lymphoid stem cell
29
Where does leukopoiesis occur?
Red bone marrow
30
Describe how interleukins and Colony-stimulating factors regulate leukopoiesis
Interleukins and Colony-stimulating factors are classes of signaling molecules that bind to a hemocytoblast membrane and signal for it to differentiate. Different molecules within these classes of proteins will cause the undifferentiated stem cell to mature into the five different types of leukocytes.
31
How are platelets (3 steps) produced?
1. Thrombopoietin causes hemocytoblasts to mature into Megakaryocytes in bone marrow.
2. These megakaryocytes then extend themselves into the blood stream and these extensions break.
3. The fragment left in blood stream is called a thrombocyte or platelet.
32
What is the function of a thrombocyte?
To form a plug during the process of blood clotting.
33
What are three (3) possible causes of thrombocytopenia?
1. Dysfunctional bone marrow (aplastic anemia)
2. Overuse of platelets (rheumatoid arthritis and lupus)
3. Platelets trapped in enlarged spleen
34
What are three (3) symptoms of thrombocytopenia?
1. Bleeding from gums or nose
2. Pinhead sized red marks on skin called petechiae
3. Blotches and bruises
35
What is the main function of albumin?
Albumin cannot cross capillary walls so it tends to pull water into capillaries. It accounts for 80% of the colloid osmotic pressure.
36
Where is albumin produced?
The liver
37
Are clotting proteins that are freely floating in the blood plasma in active or inactive form?
Inactive
38
What happens when clotting proteins in blood plasma are activated?
They become a part of the blood clot cascade that eventually forms fibrin.
39
What are the functions of hormones in the blood?
Chemical messengers between cells, tissues or organs.
40
What are three (3) metabolic waste products contained in the blood plasma?
1. Urea
2. Uric acid
3. Creatinine
41
What are five (5) categories of nutrients contained in the blood plasma?
1. Glucose
2. Amino acids
3. Lipids
4. Vitamins
5. Minerals
42
What are six (6) electrolytes contained in the blood plasma?
1. Sodium
2. Chloride
3. Potassium
4. Calcium
5. Phosphates
6. Bicarbonate
43
What are two (2) respiratory gases contained in the blood plasma?
1. Oxygen
| 2. Carbon dioxide
44
What are two (2) functions of water in blood plasma?
1. Maintain blood volume
| 2. Absorb and transfer heat
45
What are the three (3) layers of centrifuged blood and their typical relative concentrations?
1. Plasma (~55%)
2. Buffy coat (<1%)
3. Hematocrit (~45%)
46
What is contained in the hematocrit?
Red blood cells
47
What two (2) things are contained in the buffy coat?
1. Thrombocytes
| 2. Leukocytes
48
What color is blood plasma?
Straw (pale yellow)
49
What is the name of the committed stem cell that will eventually become an erythrocyte?
Proerythrocyte
50
What is a reticulocyte?
An immature red blood cell that circulates in blood stream for about a day before maturing into an erythrocyte.
51
Describe the process of erythropoiesis (six steps)
1. Kidneys detect hypoxia (lack of oxygen in blood)
2. Kidneys release erythropoietin (EPO)
3. Erythropoietin is primary signal molecule that causes hemocytoblasts to enter erythroid lineage (path to become erythrocyte)
4. Hemocytoblasts develop into proerythrocytes
5. Proerythrocytes eject nucleus and develop into Reticulocytes
6. Reticulocytes enter blood stream and become Erythrocytes
52
Describe the relationship between pernicious anemia, Vitamin B12 and Intrinsic Factor.
Intrinsic Factor is a protein released by cells in the stomach that allow your intestines to absorb Vitamin B12, which is needed to make red blood cells.
53
Describe the chemical structure of Hemoglobin
4 protein subunits called Globins with an iron-containing Heme group in the center of each subunit.
54
What is the function of Hemoglobin?
Each heme within a hemoglobin (4 total) can carry one O2 molecule.
55
What is the color of oxyhemoglobin?
Bright red
56
What is the color of deoxyhemoglobin?
Dark red
57
What are the two (2) non-toxic iron containing molecules used for storage?
1. Ferritin
| 2. Hemosiderin
58
What is the non-toxic iron containing molecule used for transportation?
Transferrin
59
Where is iron found and in what quantities (4 places)?
1. Blood (65%)
| 2. Liver/spleen/bone marrow (35%)
60
What are four (4) ways iron is removed from the body?
1. Urine
2. Feces
3. Sweat
4. Menstruation
61
What controls iron absorption and what does the quantity absorbed depend upon?
Iron absorption is controlled by intestinal cells and it depends on the amount of stored iron.
62
Describe two (2) ways old RBCs are removed from blood circulation.
1. Macrophages in liver, spleen and lymph nodes remove them. (90%)
2. old RBCs hemolyze in blood stream and the fragments are engulfed by macrophages. (10%)
63
What happens to an RBC's hemoglobin when it is engulfed by a macrophage?
Hemoglobin is broken down into heme and globin.
64
What happens to the globin once hemoglobin has been broken down by a macrophage?
Globin is broken down into amino acids by macrophage which are used by macrophage or released into blood stream.
65
What happens to heme once hemoglobin has been broken down by a macrophage (3 steps)?
1. Iron is separated from heme.
2. Leftover heme is converted into (1) unconjugated bilirubin by macrophage, (2) bound bilirubin by albumin in blood stream (3) conjugated bilirubin by liver cells and is then secreted into small intestine along with bile.
3. Iron is stored in macrophages or released into blood stream where it binds to transferrin and sent to storage.
66
What happens to conjugated bilirubin once it is secreted into small intestine (2 steps)?
1. Bacteria in intestine convert conjugated bilirubin into urobilinogen which gives feces its color.
2. Some urobilinogen reenters blood stream and is filtered by kidneys and excreted, giving urine a yellow color.
67
What is jaundice?
A yellowish pigmentation of skin and sclera of eyes from hyperbilirubinemia (increased levels of bilirubin in the blood).
68
What are three (3) causes of jaundice?
1. Liver disease
2. Biliary obstruction
3. Accelerated RBC destruction
69
What is hemostasis?
Blocking the flow of blood.
70
What are three (3) mechanisms that contribute to hemostasis?
1. Vascular spasm
2. Platelet plug formation
3. Clotting of blood
71
How does vascular spasm contribute to hemostasis (3 ways)?
1. Localized vasoconstriction of damaged blood vessel prevents blood loss.
2. Epinephrine released by adrenal glands causes systemic vasoconstriction.
3. Vasoconstriction gives time for platelet plug to form.
72
How is the platelet plug formed? (2 steps)
1. Von Willebrand Factor released from damaged collagen fibers of subendothelial tissue in blood vessel activates platelet and causes them to stick together.
2. Platelets release (1) Seretonin to increase vascular spasm and (2) ADP and (3) Thromboxane to attract more platelets.
73
What are clotting factors?
Proteins that exist in blood circulation that are typically inactive. Sequential activation leads to clot formation.
74
What are blood clots composed fo?
Polymers (end-to-end chains) of the protein Fibrin
75
What is the inactive form of fibrin?
fibrinogen
76
What prevents fibrinogen from forming clots in the blood stream?
The fibrin-to-fibrin bonding sites are "capped" making it inactive.
77
What protein is needed to convert fibrinogen to fibrin?
Thrombin
78
What is the inactive precursor to thrombin?
Prothrombin
79
What ion is required for the polymerization of fibrin?
Calcium (Ca2+)
80
What protein is needed to convert Prothrombin to Thrombin?
Prothrombin activator
81
What are the two (2) pathways that lead to the conversion of Prothrombin to Thrombin?
1. Intrinsic Pathway
| 2. Extrinsic Pathway
82
Describe the Intrinsic Pathway of blood clot formation (4 steps)?
1. Damage to the vessel wall stimulates the activation of a cascade of clotting factors
2. Cascade results in the activation of factor X.
3. Factor X is an enzyme that converts prothrombin to thrombin.
4. Thrombin converts fibrinogen to fibrin monomers, which then polymerize to form a fibrin mesh.
83
Describe the Extrinsic Pathway of blood clot formation
1. Triggered by tissue damage outside of the blood vessel.
2. Damage to tissue stimulates the activation of tissue thromboplastin, an enzyme that catalyzes the activation of factor X.
3. Factor X is an enzyme that converts prothrombin to thrombin.
4. Thrombin converts fibrinogen to fibrin monomers, which then polymerize to form a fibrin mesh.
84
What clotting factor is the "Prothrombin activator"?
Factor X
85
How does the anticoagulant Coumadin (warfarin) work?
It inhibits the synthesis of vitamin-K dependent clotting factors.
86
How does the anticoagulant Heparin work?
Inhibits thrombin which prevents conversion of fibrinogen to fibrin.
87
What cell can release heparin?
Basophils
88
What effect gives aspirin anticoagulant properties?
Low-dose, long-term aspirin use irreversibly blocks the formation of thromboxane in platelets, producing an inhibitory effect on platelet aggregation.
89
What are the three phases of coagulation?
1. Formation of Prothrombin activator.
2. Thrombin formation.
3. Fibrin mesh formation.
90
What is diapedesis
The passage of blood cells (especially white blood cells) through the intact walls of the capillaries.
91
What is chemotaxis?
Movement of an organism (e.g. white blood cells) in response to a chemical stimulus.
92
What is phagocytosis?
The process by which a cell (e.g. macrophage) engulfs a solid particle to form an internal vesicle known as a phagosome.
93
What is a thrombus?
A stationary blood clot.
94
What is an embolus?
A moving blood clot.
95
What is leukopenia?
A decreased count of all white blood cells.
96
What is leukemia?
An overproduction of abnormal or immature white blood cells.
97
What is the cause of leukemia?
Dysfunctional bone marrow that is unable to produce white blood cells properly.
98
What is leukocytosis?
Above average count of leukocytes.
99
What is polycythemia vera?
Overproduction of red blood cells from uncontrolled erythropoiesis caused by bone marrow cancer.
100
What is secondary polycythemia?
Increased production of red blood cells resulting from chronic hypoxia (resulting from increased elevation, etc.)
101
What is hemorrhagic anemia?
Low red blood cell count from massive blood loss.
102
What is hemolytic anemia?
Low red blood cell count due to premature destruction (caused by transfusion, autoimmune disorders, etc.)
103
What is aplastic anemia?
Destruction of red bone marrow
104
What is iron deficiency anemia?
Low hemoglobin resulting from inadequate iron intake.
105
What is hemophilia?
Genetic disorder resulting in the inability to synthesize one or more clotting factors.
106
How is hemophilia treated?
Reliance on blood/plasma transfusions to supply missing clotting factors.
107
What is thrombocytopenia?
Deficiency of platelets.
108
What are two (2) main functions of the lymphatic system?
1. To collect and transport fluids from intercellular spaces back to the veins in the blood system
2. Filter out microorganisms and foreign substances
109
What are three (3) divisions of the lymphatic system?
1. Lymphatic fluid (Lymph)
2. Lymphatic vessels (Lymphatics)
3. Lymphoid tissue
110
What is the function of lymphatics?
Drain fluid and plasma proteins from intercellular spaces and return it to blood to maintain blood volume.
111
What are the three sizes of lymphatic vessels from smallest to largest?
1. Collecting vessels
2. Trunks
3. Ducts
112
Where are lymphatic capillaries located?
Lymphatic capillaries are weaved through capillary bed of blood vessels
113
Explain how lymphatic capillaries only allow fluid to enter in one direction (3 steps)
1. Capillaries contain minivalves
2. When interstitial (fluid outside of capillary) pressure is high, the valve opens and fluid enters capillary.
3. When lymph fluid pressure is equal to interstitial pressure the valve closes.
114
Describe the relative sodium, potassium and chloride concentrations of EXTRACELLULAR fluid
1. High sodium
2. Low potassium
3. High chloride
115
Describe the relative sodium, potassium and chloride concentrations of INTRACELLULAR fluid
1. Low sodium
2. High potassium
3. Low chloride
116
Where is most of the body's water located?
Intracellular fluid (66%)
117
What is a lacteal?
a lymphatic capillary that absorbs dietary fats in the villi of the small intestine.
118
What is chyle?
Fatty lymph that is originally transported by lacteal and eventually merges with larger lymphatic vessels.
119
What are two (2) functions of lymph nodes?
1. To filter lymph through phagocytosis by macrophages
| 2. To house lymphocytes that monitor lymph for foreign antigens.
120
Where are lymph nodes located and where are they clustered?
Along the lymphatic vessels. They are clustered in the inguinal, axillary and cervical regions.
121
What are afferent lymphatic vessels?
Lymphatics that bring lymph to lymph node.
122
What are four (4) lymphatic organs?
1. Lymph nodes
2. Spleen
3. Thymus
4. MALTs
123
What blood vessels are superficial lymphatics located nearest?
Veins
124
What blood vessels are deep lymphatics located nearest?
Arteries
125
What side of the body is the spleen located?
Left
126
What are three (3) functions of the spleen?
1. Break down old RBCs and recycle iron
2. Lymphocyte production
3. Surveillance and response to pathogens
127
How does the body respond when the spleen is damaged or missing?
Liver and bone marrow take over its functions.
128
What Thymus function is associated with the lymphatic system?
T-cell maturation
129
What happens to a person's thymus as they age?
It shrinks (thymic atrophy).
130
What causes lymph to move inside the lymphatic vessels (3 ways)?
1. Valves prevent backflow, similar to veins.
2. Muscle pump (as muscles contract lymph is moved)
3. Respiratory pump (changes in pressure cause lymph to move)
131
The thoracic duct empties into what vein?
Left subclavian vein
132
The right lymphatic duct empties into what vein?
Right subclavian vein
133
What four (4) areas of the body does the thoracic duct drain?
1. Legs
2. Left side of head
3. Left thorax
4. Left arm
134
What three (3) areas of the body does the right lymphatic duct drain?
1. Right side of head
2. Right thorax
3. Right arm
135
Describe the anatomy of lymphatic vessels
Composed of the same tunics (tunica externa, tunica media, tunica interna) as veins
136
Describe the composition of lymph (3 components)
1. Similar to blood plasma
2. Contains white blood cells (especially lymphocytes)
3. Plasma proteins.
137
What is lymphedema?
Swelling caused by localized fluid retention
138
What causes lymphedema?
Blockage of a lymphatic vessel
139
What are the five (5) main trunks of the lymphatics?
1. Jugular
2. Subclavian
3. Bronchomediastinal
4. Lumbar
5. Intestinal
140
What five (5) components comprise the innate immune system?
1. physical epithelial barriers (e.g. skin, pH of stomach)
2. phagocytes
3. dendritic cells
4. Natural Killer cells
5. plasma proteins
141
What are the two (2) components of the adaptive immune system?
1. Humoral immunity
| 2. Cell-mediated immunity
142
Describe the function of the innate immune system
the innate immune system consists of cells and proteins that are always present and ready to mobilize and fight microbes at the site of infection.
143
Describe the function of the adaptive immune system
adaptive immune system "adapts" to pathogens that are able to overcome the innate immune system
144
What three (3) cell types act as antigen-presenting cells
1. Dendritic cells
2. Macrophages
3. B cells
145
What type of lymphocyte mediates humoral immunity?
B Cell
146
What type of lymphocyte mediates cell-mediated immunity?
T Cell
147
Describe the specificity of innate immune system
can recognize general classes of pathogens (virus, bacteria, fungi, etc.) but cannot make fine distinctions
148
Describe the specificity of adaptive immune system
recognizes highly specific antigens
149
A lymphocyte can differentiate into what three (3) cell types and where do they mature?
1. B Cell (Bone-marrow)
2. T Cell (Thymus)
3. Natural Killer Cell
150
What do natural killer cells do?
NK cells kill infected or damaged cells and have less specific receptors than B cells and T Cells.
151
How do B and T cells develop specialized receptors?
During maturation, random genetic mutations cause them to develop a unique receptor with very high specificity.
152
What is a naive lymphocyte?
A lymphocyte that has not yet encountered an antigen that is specific to its receptors.
153
Describe the immune system process of recirculation
Naive lymphocytes move between peripheral lymphoid tissues (lymph nodes and spleen) and blood stream "looking" for the antigen specific to its receptors.
154
What is the main job of antigen presenting cells (APCs)?
To capture and display antigens to lymphocytes.
155
Where are antigen presenting cells located?
In the periphery where they survey tissues for antigens
156
What are MHCs?
Major Histocompatibility Proteins are glycoproteins on a cell's surface that identity it as self.
157
What is an antigen presenting cells response when it detects an antigen (2 steps)?
1. Displays antigen on its surface using MHCs
| 2. Move to lymph node
158
What is an effector cell (immune)?
The cells that actually eliminate the microbe.
159
What are the 5 types of effector cells (immune)?
1. Helper T Cells
2. Cytotoxic T Cells
3. Plasma cells
4. Natural Killer cells
5. Macrophages & Granulocytes
160
The inflammatory response belongs to which division of the immune system?
Innate immune system
161
What are the four cardinal signs of inflammation?
1. Redness
2. Heat
3. Swelling
4. Pain
162
What are toll-like receptors?
Protein receptors that recognize antigens on microbes and releases cytokines.
163
What causes inflammation (4 chemicals)?
Damaged cells release chemicals:
1. Histamine (basophils and platelets)
2. Cytokines (toll-like receptors)
3. Prostaglandins
4. Kinins
164
How do response chemicals cause inflammation (2 ways)
1. Increased vasodilation
| 2. Increased permeability of capillaries
165
What are four (4) benefits of inflammation?
1. Prevents spread of microbe
2. Gets rid of debris and pathogen
3. Increase number of leukocytes
4. Prepares for repair
166
What are four (4) effects of kinins when released?
1. induce vasodilation
2. increase vascular permeability
3. cause smooth muscle contraction
4. induce pain.
167
What are two (2) effects of histamine when released?
1. arteriole dilation
| 2. increased venous permeability.
168
What causes fever?
Leukocytes and macrophages release pyrogens which act on hypothalamus and raise body temperature.
169
What are two (2) the benefits of fever?
1. Liver and Spleen take in Iron and Zinc which is needed by bacteria to reproduce
2. Increase cell metabolism
170
Describe the initial response of the innate immune system to a pathogen (3 steps)
1. Inflammation occurs.
2. Neutrophils arrive on scene and release Leukocytosis Inducing Factor which signals for more granuloytes and macrophages to come.
3. Phagocytes remove pathogen or hold it at bay until adaptive immune system is active.
171
Describe the adaptive immune system response to a pathogen (2 steps)
1. APCs detect antigens on pathogen and bring them to lymphocytes.
2. Activated lymphocytes divide and mature, producing effector cells that will eliminate the microbe.
172
What kind of microbes does humoral immune system specialize in eliminating?
Extracellular microbes
173
What are the effector products of humoral immunity?
Antibodies
174
What is a key difference between the receptor activation of T cells and B cells (compare and contrast)?
B cells are capable of recognizing many different chemical structures with the antibodies embedded in their plasma membrane, while T cells are only able to recognize small peptides presented by APCs.
175
What is clonal selection?
When a B cell is activated by detecting its specific antigen, only B cells containing the same exact receptor (its "clones") are selectively activated.
176
What is clonal expansion?
Activated B cells, including all of its clones, divide to prepare to fight off infection and to keep up with the reproduction of the microbe.
177
What are plasma cells?
Differentiated activated B cells that secrete antibodies.
178
What are four (4) ways an antibody removes a microbe?
1. Neutralization
2. Opsonization (flagging) & phagocytosis
3. Activation of complement proteins
4. Precipitation and Agglutination
179
What happens to plasma cells as humoral immunity response winds down (2 possibilities)
1. Some plasma cells undergo apoptosis.
| 2. Others migrate to bone marrow where they will produce antibodies for years.
180
What are memory cells?
Differentiated activated B cells that will remain for years after an infection.
181
Why is the secondary response faster than the primary response to a pathogen?
Memory cells respond quicker and more effectively than naive lymphocytes.
182
What is another name for a CD4+ T Cell?
Helper T Cell
183
What is another name for a CD8+ T Cell?
Cytotoxic T Cell
184
What do MHC I molecules do?
Display peptide antigens located in the cytoplasm of the cell they are located on.
185
Where are MHC I molecules located?
On the membrane of all healthy, nucleated cells.
186
Which T cell is better at recognizing MHC I molecules and the antigens they present?
CD8+ T Cell (Cytotoxic T Cell)
187
Where are MHC II molecules located?
On the membrane of APCs.
188
What do MHC II molecules do?
Display peptide antigens located in the vesicles of APCs.
189
Which T cell is better at recognizing MHC II molecules and the antigens they present?
CD4+ T Cell (Helper T Cell)
190
What kind of microbes does the cell-mediated immunity specialize in eliminating?
Microbes located within cells.
191
How does a CD4+ T Cell become activated? (3 steps)
1. An APC engulfs a pathogen and travels to lymph tissue.
2. APC presents antigen via MHC II molecule.
3. CD4+ T Cell is activated if it is specific to that antigen.
192
How does a CD8+ T Cell become activated? (3 steps)
1. A virus or other microbe will enter a healthy, nucleated cell.
2. Foreign antigen is presented on MHC I molecule.
3. CD8+ T cell is activated if it is specific to that antigen.
193
What happens after a T cell becomes activated?
Once a clone has been selected it goes through clonal expansion (rapid division).
194
What do Helper T cells do once they are activated?
Differentiate into different subsets of Helper T cells that release cytokines that have various effects.
195
How are memory T cells formed?
The initial clonal expansion also stimulates production of memory T cells that will stay in the body for years.
196
What are the two (2) steps to make a T lymphocyte self tolerant?
1. Positive Selection (Must recognize self-MHC)
2. Negative Selection (Must not recognize self-antigens).
Cells that fail either selection go through apoptosis.
197
What is another name for antibodies?
Immunoglobulins
198
Describe the structure of immunoglobulins (two components)
1. Constant region
| 2. Variable region (antigen bonding site)
199
How many polypeptides compose an immunoglobulin?
Four. 2 Light (only on variable region) and 2 Heavy
200
What are the five Immunoglobulin classes?
1. IgM
2. IgA
3. IgD
4. IgG
5. IgE
201
What are two (2) important characteristics of IgM?
1. First immunoglobulin produced
| 2. Activation of complement
202
What is an important characteristic of IgA?
Located in mucous
203
What is an important characteristic of IgD
Naive B Cell Receptor
204
What are two (2) important characteristics of IgG?
1. Most abundant
| 2. Crosses placenta (neonatal immunity)
205
What is an important characteristic of IgE?
Receptors on mast cells bind IgE with high affinity causing hypersensitivity (allergies).
206
What is pus?
Mixture of neutrophils, cell debris, and pathogens resulting from failure to clean up site of infection.
207
What are Regulatory T Cells?
Component of the immune system that suppress immune responses of other cells.
208
What is MHC restriction?
T cell will recognize a peptide antigen only when it is bound to a host body's own MHC molecule
209
What is the function of complement proteins?
Complement proteins are a part of the innate immune system and are normally inactive. When activated they form the Membrane Attack Complex (MAC) which leads to lysis and death of foreign organism.
210
What is the effect of AIDS on the body?
Targets CD4+ Cells and destroys helper T cells.
211
What is the effect of multiple sclerosis on the body?
Autoimmune destruction of myelin sheath of CNS.
212
What is the effect of Systemic Lupus Erythematous?
Anti-DNA antibodies found in kidneys, blood vessels, brain & joints
213
What is the effect of Rheumatoid Arthritis?
Autoimmune destruction of joints
214
What causes anaphylaxis?
Mast cells release histamine causing vasodilation and bronchial constriction.
215
What is the function of interferons (IFN)?
When a host cell becomes infected by a pathogen it will release interferons to warn nearby cells to ramp up their anti-pathogen defenses
216
What are MALT?
Mucosa-associated Lymphatic Tissues
217
What are three (3) types of MALT?
1. Tonsils
2. Peyer's Patches
3. Appendix
218
Where are tonsils located? (4 locations)
1. Palatine tonsils (back of throat)
2. Linguil tonsils (base of tongue)
3. Pharyngeal tonsils (posterior nasopharynx)
4. Tubal tonsils (surround auditory tube)
219
What is the function of MALT?
A defense against invading organisms. Contain crypts that trap bacteria.
220
What are the seven (7) steps of phagocytosis?
1. Chemotaxis and adherence of microbe to phagocyte.
2. Ingestion of microbe by phagocyte.
3. Formation of phagosome.
4. Fusion of phagosome with lysosome forming phagolysosome.
5. Digestion of ingested microbe by enzymes.
6. Formation of residual body containing indigestible materials.
7. Discharge of waste materials.
