19+20

Question 1

Yolk-sac phase, hepatic phase, and bone marrow phase

Answer 1

yolk = hematopoiesis begins week 3; formation of blood islands

hepatic = major blood forming organ in second trimester

bone marrow = begins during second trimester
main contributor after birth

Question 2

hematopoiesis after birth? most to least

Answer 2

1. vertebral and pelvis
2. sternum
3. ribs
4. lymph nodes
5. femur
6. tibia

Question 3

What do the pluripotent stem cells give rise too?

Answer 3

Myeloid stem cell and lymphoid stem cell

Question 4

myeloid stem cell?

Answer 4

give rise too:

1. proerythrocyte (RBC)
2. megakaryocyte (thrombocytes)
3. eosinophilic myeloblast (eosinophils)
4. basophilic myeloblast (basophils)
5. myeloblast (neutrophil)
6. monoblast (monocytes)

Question 5

lymphoid stem cell?

Answer 5

T lymphoblast and B lymphoblast

T-cell and B-cell

Question 6

endosteal niche

Answer 6

found in spongy bone

used for storage of stem cells, self-renewal, and inhibition of differentiation

Question 7

Vascular niche

Answer 7

found in bone marrow

Function:
support and promote differentiation
secrete growth factors

Question 8

Yellow vs red bone marrow

Answer 8

Red: active hematopoiesis

yellow: fat, capillaries, reticular cells, inactive hematopoiesis

Question 9

Erythropoietin / thrombopoietin / cytokines

Answer 9

Erythropoietin = produced by the kidney’s to increase RBC precursors

thrombopoietin = hormone from the liver to stimulate platelet formation

cytokines = stimulate proliferation

Question 10

What stimulates leukocyte production?

Answer 10

colony-stimulating factor and interleukin

Question 11

Erythropoiesis

Answer 11

stimulated by hypoxia

1. proerythroblast
2. basophilic erythoblast
3. polychromatophilic erythoblast
4. orthochromatophilic erythoblast
5. reticulocyte
6. RBC

Question 12

Granulopoiesis

Answer 12

1. myeloblasts
2. promyeloblast (azurophilic granules)
3. myeloblast (specific granules)
4. metamyelocyte
5. band (horseshoe nucleus)
6. mature form

Question 13

MONOCYTOPOIESIS

Answer 13

1. monoblasts
2. promonocytes
3. monocytes
4. once in tissue = macrophages

Question 14

THROMBOPOIESIS

Answer 14

1. megakaryoblast
2. megakaryocyte
3. platelets are formed from the fragments of the megakaryocyte cytoplasm

Question 15

LYMPHOPOIESIS

Answer 15

1. lymphoblasts
2. prolymphocytes

from bone marrow to thymus = T-cells

remain in bone marrow = B-cells

NK cells

Question 16

The role of vitamin K and gamma carboxylation

Answer 16

Required for hepatic synthesis of prothrombin (factor II)

factors VII, IX, X, and protein C+S

Question 17

Vit K is a coenzyme for what enzyme

Answer 17

gamma- Glutamyl carboxylase

Question 18

What is the benefit of gamma- carboxylation

Answer 18

allows for the binding of Ca that allows for efficient clotting

Question 19

What two things are sensitive to Vitamin K

Answer 19

1. INR

2. Factor VII

Question 20

what does calcium chelators do?

Answer 20

they bind to all the Ca in the blood, this no clotting occurs

Question 21

What do high levels of D-dimers indicate

Answer 21

the possibility of deep vein thrombosis

high risk for pulmonary embolism

Question 22

The roles and prostacyclin and NO?

Answer 22

these chemicals are released by the endothelium to prevent aggregation

prostacyclin is an antagonist of thromboxane A2

Question 23

Antithrombin III

Answer 23

Binds to and inhibits factor Xa, thrombin (IIa) and other activated clotting factors

Question 24

role of protein C and S

Answer 24

Proteins C and S act together to inactivate cofactors Va and VIIIa of coagulation cascade

protein S is a cofactor of protein C

protein C is activated by the binding of thrombomodulin to thrombin

Question 25

The role of plasmin

Answer 25

Plasmin causes fibrinolysis releasing fibrin degradation products (D -dimers).

Question 26

Aspirin

Answer 26

inhibits thromboxane A2 formation in platelets irreversible inhibitor of COX prevents clots

Question 27

heparin

Answer 27

activates antithrombin III and inactivates thrombin prevents clots

Question 28

warfarin

Answer 28

Blocks VKOR in the liver and prevents the activation of Vit. K oral anticoagulant

Question 29

streptokinase

Answer 29

Converts plasminogen to plasmin enabling dissolution of clots

Question 30

Tissue plasminogen activator

Answer 30

used to dissolve a thrombus

Question 31

Hemophilia A and B

Answer 31

X-linked recessive disorder ``` bleeding time = normal platelet count = normal INR = normal APTT = increased (defect in intrinsic pathway) ```

Question 32

How to differentiate between hemophilia A and B

Answer 32

A = factor VIII deficiency B = factor IX deficiency

Question 33

Von Willebrand disease

Answer 33

``` bleeding time = prolonged platelet count = normal APTT = prolonged INR = normal vWF = low ``` defect in platelet plug formation instability of factor VIII

Question 34

Thrombocytopenia

Answer 34

increased bleeding time and low platelet count

Question 35

increased bleeding time, but normal/ low platelet count?

Answer 35

platelet receptor defects GpIb defect: Bernard-Soulier syndrome GpIIb/IIIa defect: Glanzmann Thrombasthenia