Lesson 6 - The Circulatory System: Blood Flashcards
1
Q
leukocytes
A
WBC’s; blood cells that protect against infection and other diseases
2
Q
what is the least abundant formed element?
A
white blood cells
3
Q
how long do WBCs last in the bloodstream?
A
only a few hours in the blood before moving to tissues
4
Q
leukocytes have a _____ nucleus
A
conspicuous
5
Q
all WBCs have lysosomes called _____ _____
A
nonspecific granules
6
Q
granulocytes have _____ _____
A
specific granules
7
Q
specific granules
A
contain enzymes and other chemicals employed in defense against pathogens
8
Q
granulocytes (3)
A
neutrophils
eosinophils
basophils
9
Q
neutrophil
A
also called polymorphonuclear leukocytes (PMNs) because of the varied nuclear shapes
10
Q
what WBC is the first to attack bacteria?
A
neutrophils
11
Q
degranulations
A
occurs when lysosome granules fuse to endosomes containing phagocytized pathogen; occurs in neutrophils
11
Q
what do neutrophils do in a bacterial infection? (2)
A
phagocytize bacteria and release antimicrobial chemicals to increase inflammation and attract other phagocytes to the are
12
Q
what cell type numbers fluctuation greatly depending on the day/night cycle, seasonality, and with the phases of a menstrual cycle?
A
eosinophils
13
Q
what cell type increases with parasitic infections?
A
eosinophils
14
Q
when do numbers of eosinophils increase? (4)
A
- parasitic infections
- allergies
- collagen diseases
- diseases of the spleen and central nervous system
15
Q
what types of things do eosinophils phagocytize? (3)
A
- antigen-antibody complexes
- allergens
- inflammatory chemicals
16
Q
what enzymes do eosinophils release? (2)
A
- enzymes that weaken or destroy parasites such a worms
- enzymes that counter the inflammatory effects of neutrophils and mast cells
17
Q
what cell type increases with chickenpox, sinusitis, and diabetes?
A
basophils
18
Q
what is histamine?
A
a vasodilator; dilates blood vessels and speeds flow of blood to an injured area
19
Q
what is herapin?
A
an anticoagulant; prevents blood clotting and promotes the mobility of other WBCs in the area
20
Q
both _____ and _____ increase local inflammation initiated by mast cells
A
histamine, heparin
21
Q
basophils secrete _____ and _____
A
histamine, heparin
22
Q
microphages (2)
A
neutrophils and eosinophils
23
Q
what causes pus formation?
A
a mixture of dead neutrophils, cellular debris, and waste products during the immune response
24
agranulocytes
lack specific granules and include lymphocytes and monocytes
25
what things do lymphocytes destroy? (3)
- cancer
- foreign cells (?)
- virally infected cells
26
lymphocytes present _____ to activate the immune response
antigens (APC)
27
visual appearance of a stained lymphocyte
- variable amounts of bluish cytoplasm
- ovid/round
- uniform dark violet
28
visual appearance of a stained basophil
coarse, dark violet granules
29
when do lymphocyte numbers increase?
diverse infections and immune responses
30
what do lymphocytes do? (2)
- coordinate actions of other immune cells
- secrete antibodies and provide immune memory
31
when do monocyte numbers increase?
in viral infections and inflammation
32
what are monocytes called when the leave the bloodstream and enter tissues?
they transform into macrophages
33
what do monocytes do?
phagocytize pathogens and debris and act as antigen-presenting cells (APCs)
34
what do monocytes secrete?
substances that attract immune cells and fibroblasts to an injury site
35
what do fibroblasts produce?
scar tissue to seal off the injured area
36
leukopoiesis
production of white blood cells
37
what happens in the beginning of leukopoiesis?
hematopoietic stem cells differentiate into distinct types of colony-forming units
38
three types of CFUs
1. myeloblasts
2. monoblasts
3. lymphoblasts
39
myeloblasts form (3)
neutrophil, eosinophils, and basophils
40
monoblasts form...
monocytes
41
lymphoblasts
forma ll types of lymphocytes
42
red bone marrow stores what type of WBCs? (2)
granulocytes and monocytes
43
when do monocytes complete development?
when they enter peripheral tissue and become macrophages
44
when do granulocytes leave the blood?
4-8 hours, live another 4-5 days in tissues
45
when do monocytes leave the blood?
leave in about 20 hours, enter tissues, become macrophages, and live for a few years
46
lymphocytes provide
long term immunity
47
how are lymphocytes recycled?
from blood to tissue fluid to lymph and back to blood
48
where do all WBCs (except T cells) develop?
in the bone marrow
49
hematopoietic stem cells produce WBC and _____
RBC
50
leukopenia
low WBC count, below 5,000 WBC/uL
51
causes of leukopenia (6)
- radiation
- poisons
- infectious disease
- cancer
- autoimmune disorders
- drugs that destroy/damage bone marrow cells
52
effects of leukopenia
elevated risk of infection
53
leukocytosis
high WBC count, about 10,000 WBC/uL
54
causes of leukocytosis (3)
- infection
- allergy
- disease that increases WBC production
55
differential WBC count
identifies what percent of the total WBC count consists of each type of leukocyte
56
leukemia
cancer of hematopoietic tissue, usually producing a very high number of circulating leukocytes
57
effects of leukemia (3)
normal cell percentages disrupted, impaired clotting, and open to opportunistic infections
58
types of leukemia (4)
- myeloid leukemia
- lymphoid leukemia
- acute leukemia
- chronic leukemia
59
myeloid leukemia
uncontrolled granulocyte production
60
lymphoid leukemia
uncontrolled lymphocyte or monocyte production
61
acute leukemia (3)
| not acute as is over soon
appears suddenly, progresses rapidly, death within months
62
chronic leukemia
undetected for months, survival time is three yearsc
63
complete blood count (CBC) (5)
profile of data on multiple blood values:
- hematocrit
- hemoglobin concentration
- total counts for RBCs, reticulocytes, WBCs, and platelets
- differential WBC count
- RBC size and hemoglobin per RBC
64
hemostasis
cessation of bleeding, involving platelets
65
platelets
small fragments of megakaryocytes found in bone marrow
66
thrombocytopenia
platelet deficiency
67
causes of thrombocytopenia (4)
- autoimmune disorders
- bacteria in blood
- medications
- pregnancy
68
signs of thrombocytopenia (3)
bleeding along the digestive tract, within skin, and sometimes in the CNS
69
thrombocytosis
excessive platelets
70
causes of thrombocytosis (3)
cancer, inflammation, infection
71
what do platelets contain?
granules filled with platelet secretions
72
what happens when platelets are activated?
they are capable of amoeboid movement
73
platelets secrete... (3)
- vasoconstrictors
- procoagulants
- growth factors
74
procoagulants
clotting factors that promote clotting
75
platelet growth factors do...
they stimulate mitosis to repair blood vessels
76
_____ stick together to form _____ _____ to seal small breaks
platelets, platelet plugs
77
what do platelets chemically attract? (2)
neutrophils and monocytes to sites of inflammations
78
platelets do... (2)
- initiation formation of clot dissolving enzyme
- phagocytize and destroy bacteria
79
thrombopoiesis
production of platelets
80
what triggers hematopoietic stems cells in the bone marrow to become megakaryoblasts?
thrombopoietin
81
_____ repeatedly replicate DNA without dividing
megakaryoblasts
82
megakaryocytes
cytoplasm tendrils (proplatelets) protrude into blood sinusoids so as blood flows through it splits off fragments of the megakaryocytes forming platelets
83
what are fragments of megakaryocytes called?
platelets
84
the _____ recycles worn out platelets
the speen
85
hemostasis involves three mechanisms (3)
1. vascular spasm
2. platelet plug formation
3. blood clotting (coagulation)
86
vascular spasm
starting stage of hemostasis
- immediate protection against blood loss causing constriction of a broken blood vessel
87
causes of vascular spasm (3)
- some nociceptors directly trigger constriction
- smooth muscle injury
- platelets release serotonin (vasoconstrictor)
88
step one of vascular spasms
Endothelial cells in the lining of the blood vessel contract and exposes the basement membrane to blood – the basement membrane is usually not exposed to blood
89
step two of vascular spasm
Endothelial cells release hormones called endothelins to stimulate smooth muscle contraction in blood vessel (promotes vascular spasms) and endothelial, smooth muscle, and fibroblast cell division
90
step three of vascular spasm
Endothelial cells become “sticky” to seal off the breach in the vessel – allows platelets to attach later on
91
how long does vascular spasm last?
up to 30 minutes
92
when does platelet plug formation start?
about 15 seconds after vascular spasms has started
93
broken blood vessels expose _____ and the _____ _____
collagen, basement membrane
94
platelet plug formation: step 1
platelet pseudopods stick to damaged vessel and other platelets
95
platelet plug formation: step 2
pseudopods contract, drawing together a platelet plug
96
platelet plug formation: step 3
platelets undergo degranulation releasing ADP, Thromboxane A2, and serotonin
97
platelet plug formation: step 4
continued via positive feedback cycle until the break in the vessel is sealed
98
endothelium of intact vessels is very smooth and coated with _____
| p
prostacyclin
99
prostacyclin
a platelet repellent to prevent platelet adhesion at non-damaged areas
100
degranulation
exocytosis of cytoplasmic granules and factors that promote hemostasis
101
platelet secretions: ADP
| what does it do?
attracts and degranulation more platelets
102
platelet secretions: Thromboxane A2
an eicosanoid, promotes platelet aggregation, degranulation, and vasoconstriction
103
platelet secretions: serotonin
a vasoconstrictor
104
factors that limit the growth of the platelet plug include: (5)
1. prostacyclin
2. inhibitory compounds released by other WBCs
3. circulating enzymes break down ADP
4. negative feedback from serotonin
5. development of blood clot isolates area
105
prostacyclin
| what cells release this?
released by endothelial cells to inhibit platelet aggregation
106
high levels of serotonin block the action of _____
ADP
107
coagulation
conversion of fibrinogen to fibrin threads to form the framework of a clot
108
procoagulants use a _____ _____
reaction cascade
109
reaction cascade
activate one factor and it will activate the next
110
when does coagulation start?
about 30 seconds after vascular spasm has started
111
where are procoagulants usually produced?
the liver
112
two pathways of coagulation
extrinsic and intrinsic
113
extrinsic mechanism for coagulation
| involves?
involves the blood vessel components, where clotting factors from sources outside the body are released by damaged vessels and perivascular tissues
114
how is the extrinsic mechanism of coagulation started?
tissue thromboplastin (factor III) from damaged tissues
115
after factor II is initiated, where does it go>
cascades to factor 7, 5, and 10
116
which coagulation pathway is faster?
extrinsic, it has fewer steps
117
intrinsic mechanism
involves humoral (proenzymes) using only blotting factors found in blood itself
118
what is the intrinsic mechanism of coagulation started?
contact with exposed collagen on ruptured vessel walls by platelets releasing factor 12
119
what happens after factor 12 is released?
it cascades to factor 11, 9, 8, and 10
120
both the intrinsic and extrinsic pathways of coagulation require?
calcium
121
both the intrinsic and extrinsic pathways of coagulation converge on the triggering of?
factor 5 (X), the start of the common pathway
122
the common pathway of coagulation (3)
1. activation of factor 10 leads to production of prothrombin activator
2. thrombin converts fibrinogen to fibrin
123
factor 2
prothrombin
124
fibrin molecules (monomers) bind to form
fibrin polymers
125
factor _____ crosslinks fibrin polymer starts
13
126
how does is the common pathway kept with positive feedback?
thrombin also forms prothrombin activator
127
clot retraction
platelet pseudopods adhere to fibrin starts and contract, clot becomes come compact withing 30 minutes
128
overall efficiency of coagulation can be measured with _____ _____ after a 1mm deep incision
bleeding time
129
platelet-derived growth factor (PDGF) (2)
| what secretes this? what does it do?
secreted by platelets and endothelial cells; mitotic stimulant for fibroblasts and smooth muscle to multiply and repair damaged vessels
130
fibrinolysis
the dissolution of a clot, occurs after tissue repair is completed
131
factor XII
catalyzes formation of enzyme kallikrein
132
kallikrein
converts plasminogen into plasmin
133
plasmin
a fibrin-dissolving enzyme that breaks up clots
134
controls to prevents coagulation when it isn't needed: platelet repulsion
platelets do not adhere to prostacyclin-coated endothelium
135
controls to prevents coagulation when it isn't needed: dilution (3)
- small amounts of thrombin form spontaneously in plasma
- thrombin is diluted by normal blood flow, preventing clotting
- heart slowing in shock can result in clot formation
136
controls to prevents coagulation when it isn't needed: anticoagulants
| what are they called?
antithrombin and heparin
137
antithrombin
deactivated thrombin before it can act on fibrinogen
138
heparin
| what does it do?
interferes with formation of prothrombin activator
139
where is antithrombin formed?
the liver
140
where is heparin formed?
| what type of cell?
basophils and mast cells
141
hemophilia
a family of hereditary diseases characterized by deficiencies of one clotting factor or another
142
what does hemophilia result in?
a failure for blood to clot
143
hemophilia: physical exertion can cause what? (3)
intramuscular and joint hematomas (clotted blood in tissues) and cause severe pain and eventual joint immobility
144
what level of clotting factor is enough to prevent symptoms of hemophilia?
half the normal level
145
how are the most common types of hemophilia inherited?
sex-linked recessive traits
146
classical hemophilia (hemophilia A)
missing factor VIII (83% of cases)
147
hemophilia B
missing factor IX (15% of cases)
148
thrombosis
abnormal formation of a clot in an unbroken vessel
149
thrombus
an unwanted blood clot in a vessel
150
where is a thrombus most likely to form, and in who?
the leg veins of inactive people
151
embolus
a thrombus that has broken away from the vessel wall
152
infarction
tissue death via loss of oxygen
153
thromboembolism
traveling blood clots
154
preventing unwanted clots (2)
use vitamin K antagonists such as coumarin, warfarin
155
what do coumarin and warfarin do?
they're vitamin K antagonists that prevent synthesis of clotting factors 2,7, 9, and 10 that require the vitamin
156
dissolving unwanted clots that have already formed (3)
| s.t.h.
- streptokinase
- tissue plasminogen activator
- hementin
157
streptokinase
enzyme made by streptococcus bacteria that is used to dissolve clots in coronary vessels
158
tissue plasminogen activator (TPA)
converts plasminogen into clot-dissolving plasmin
159
hementin
anticoagulant originating from a leech found in the Amazon
