Exam 3: Circulatory System- Blood Part 2

Question 1

what do agranulocytes include?

Answer 1

monocytes and lymphocytes

Question 2

monocytes

Answer 2

2-8% of leukocytes
have high amounts of lysosomes
precursor to non-lobed (mononucleated) phagocytes
can activate and attract defense cells to the damaged area

Question 3

what do monocytes mature into in the connective tissue, CNS, and bone

Answer 3

connective tissue: macrophages
CNS: microglia
bone: osteoclasts

Question 4

Monocytes as macrophages

Answer 4

• secrete neutrophil and monocyte chemotactic factors
• additional secretions attract fibroblasts to regions of injury
• function in activation of lymphocytes in specific immunity (B and T cells)

Question 5

lymphocytes and what they have roles in protecting against

Answer 5

20-40% leukocytes
protect against: 
-specific foreign antibodies
-abnormal/cancerous cells
-invading microorganisms 

play surveillance role in immunity

Question 6

3 types of lymphocytes

Answer 6

T lymphocytes: protect against foreign cells presenting specific markers/antigens

B cells: produc antibodies against specific antigens

NK cells: surveillance of abnormal cells; important in detecting cancer

Question 7

thrombocytes (platelets)

Answer 7

nonnucleated cell fragments
originate from fragmentation of giant cell, megakaryocyte
involved in clot formation
secrete chemicals that attract platelets and initiate clotting factors
contain filaments that contract blood vessel walls to minimize damaged area

when no damage they do NOT stick to eachother

Question 8

hemostasis and the 3 stages

Answer 8

the process of halting bleeding

stages: vascular, platelet, coagulation

Question 9

hemostasis: vascular stage

Answer 9

• begins right after damage, can last up to 30 minutes
• damage triggers localized sympathetic response - vasoconstriction slows bleeding
• damages endothelium secrete chemicals attracting platelets
• exposed basement membrane attracts platelets

Question 10

hemostasis: platelet stage

Answer 10

within 15s after injury

• damaged endothelium releases von Willibrand’s factor
• promotes platelet adhesion
• adhered platelets release ADP, PDGF, thromboxanes, thromboplastin, Ca

Question 11

von willibrands factor

Answer 11

promotes binding of platelets to the damaged surface

makes the surface sticky, platelet adhesion

Question 12

adhered platelets release (5 things)

Answer 12

ADP: attracts platelets
PDGF: promotes repair of vessel
Thromboxane: stimulates vessel spasms - vasoconstriction
Thromboplastin (tissue factor): clotting factor 3; initiates blood clotting!!
Ca: required for clotting factor cascade

Question 13

what initiates blood clotting

Answer 13

thromboplastin (tissue factor)

Question 14

hemostasis: coagulation

Answer 14

30s to minutes after injury
ends with conversion of serum protein fibrinogen converting to fibrin by thrombin
fibrin forms a network of fibers that traps blood cells and platelets to form clot/thrombus
initiation of clot formation is in 2 pathways

Question 15

pathways in the initiation of clot formation

Answer 15

extrinsic and intrinsic but both share a common pathway to fibrin activation

Question 16

extrinsic pathway

Answer 16

rapid, initiated by release of thromboplastin from damaged tissue
handles small actions like a scrape or papercut
may be enough

Question 17

intrinsic pathway

Answer 17

initiated by clotting factors coming in contact with exposed collagen in blood vessel walls
takes 5-10 min to begin
takes over for more serious or internal bleeding

Question 18

clotting factor XII

Answer 18

Hageman’s factor, a serine protease

Question 19

clotting factor XI

Answer 19

plasma thromboplastin, antecedent serine protease

Question 20

clotting factor IX

Answer 20

christmas factor

serine protease

Question 21

clotting factor VII

Answer 21

stable factor; serine protease

Question 22

clotting factor XIII

Answer 22

fibrin stabilising factor; transglutaminase

Question 23

common pathway

Answer 23

starts when you activate CF 10
in presence of platelets, Calcium and CF 5 turn inactive thrombin into active thrombin
thrombin activates fibrinogen into fibrin to get polymerization and CF13

Question 24

CF13

Answer 24

when activated it crosslinks individual fibrin strands to add strength to them
get stable mesh which is your fibrin clot

Question 25

intrinsic pathway in cascade

Answer 25

surface contact, damaged cells; collagen and CF12 activated (Hageman’s factor)
CF 11 thromboplastin comes in to start cascade
CF 10 can feedback and activate CF 11 to keep going
CF 11 activates CF 9 (christmas factor) which activates CF 8(antihemophilia factor)

Question 26

hemophilia

Answer 26

bleeding disease - do not clot properly - all involve intrinsic pathway

Question 27

hemophilia A

Answer 27

CF 8 - at final step to activate common pathway

on x chromosome, if someone deficient in CF 8 they will not initiate common factor through intrinsic pathway

Question 28

hemophilia B

Answer 28

CF 9 (christmas factor)
on x chromosome
see more in men than women bc women have opportunity to be heterozygous, men do not, only have one x

Question 29

hemophilia C

Answer 29

CF 11

equally seen in both sexes, on chromosome 4 - autosomal recessive not a sex linked trait

Question 30

fibrinolysis

Answer 30

as repair continues, clot needs to be dissolved
thrombin and tissue plasminogen activator, released from endothelium, activates plasmin
slow activation of plasmin to allow healing

Question 31

plasmin

Answer 31

breaks down the fibrin dissolving the clot