Hemostasis

Question 1

A zymogen is

Answer 1

An inactive substance which can be converted into an enzyme when activated by another enzyme

Question 2

(T or F) The roman numerals assigned to clotting factors are named in the order of discovery not the order of activation in the clotting cascade.

Answer 2

True

Question 3

Which clotting factor initiates the extrinsic pathway (tissue factor pathway).

Answer 3

Factor III (Tissue Factor)

Question 4

Which factor does factor III (tissue factor) activate in the clotting cascade?

Answer 4

Factor VII

Question 5

In the clotting cascade, thrombin has this action:

Answer 5

Converts fibrinogen to fibrin

And

Activates protein C

Question 6

The intrinsic pathway is initiated by which factor?

Answer 6

Factor XII

Question 7

Which factor has the greatest ability to bioregulate hemostasis (upregulate or downregulate the clotting cascade)?

Answer 7

Thrombin

Question 8

Which factor creates crosslinks of fibrin mesh during clot formation?

Answer 8

Factor XIII

Question 9

In which organ are the majority of clotting factors produced?

Answer 9

Liver

Question 10

Which clotting factors are vitamin K dependent?

Answer 10

II - 2

VII - 7

IX - 9

X - 10

Question 11

Prothrombin time (PT) evaluates the ______

Answer 11

Extrinsic pathway

Question 12

(T or F) Delayed bleeding is characteristic of secondary hemostatic disorders.

Answer 12

True

Question 13

What can lead to a prolonged prothrombin time (PT)?

Answer 13

Vitamin K deficiency

Question 14

Activated partial thromboplastin time (aPTT) evaluates the ______

Answer 14

Intrinsic system

Question 15

Hemophilia A is a deficiency of this factor:

Answer 15

Factor VII

Question 16

Which is the most common type of hemophilia?

Answer 16

Hemophilia A

Question 17

(T or F) Elongation of aPTT occurs with Von Willebrand disease.

Answer 17

True

Question 18

What are sources of Vitamin K?

Answer 18

Synthesized by intestinal flora

Green leafy vegetables

Question 19

Which enzyme is responsible for degrading fibrin during fibrinolysis?

Answer 19

Plasminogen

Question 20

Under what circumstances do protein C and protein S become activated?

Answer 20

In the presence of excess thrombin

Question 21

(T or F) Factors C and S are vitamin K dependent.

Answer 21

True

Question 22

Factor V Leiden mutation results in what?

Answer 22

Hypercoagulability

Question 23

What is is contraindicated for individuals with Factor V Leiden disease?

Answer 23

Oral birth control pills

Question 24

An elevation in aPTT suggests:

Answer 24

A deficit of functional factors in the intrinsic pathway

Question 25

Platelets stay in circulation for

Answer 25

7-10 days

Question 26

What are critical values?

Answer 26

Values determined to be so low/high they constitute a medical emergency

Question 27

The major risk associated with thrombocytopenia is

Answer 27

Spontaneous hemorrhage

Question 28

(T or F) Thrombocytopenia is associated with a wide variety of conditions.

Answer 28

True

Question 29

Which of the following is NOT an interfering factor for platelet counts? Drug intake Tobacco use High altitude Estrogen

Answer 29

Tobacco use

Question 30

A screening CBC is performed on a healthy individual. The report findings are positive for low platelets. Your next step is to:

Answer 30

Review the peripheral smear for satellite formation or platelet clumping

Question 31

Which of the following conditions is associated with a decreased MPV? ## Footnote B12 deficiency Sepsis Aplastic anemia Valvular heart disease

Answer 31

Aplastic anemia

Question 32

What is the final outcome of healthy hemostasis

Answer 32

Formation of a stable hemostatic plug

Question 33

Which of the following steps are included in primary hemostasis? ## Footnote Recruitment of RBCs to the area of injury Formation of a white thrombus Formation of a stable clot Reflexive vasoconstriction

Answer 33

Formation of a white thrombus and Reflexive vasoconstriction

Question 34

In primary hemostasis, the bleeding initially stops with:

Answer 34

Platelet adherence to subendothelial collagen fibers

Question 35

What triggers platelet morphophonology to change?

Answer 35

Activation by von Willebrand factor (vWB)

Question 36

(T or F) The two steps of hemostasis (primary and secondary) happen independently of one another and in succession.

Answer 36

False

Question 37

Which best describes aggregation in primary hemostasis? ## Footnote Platelet to RBC attachments Platelet to WBC attachments Platelet to platelet attachments Platelet to collagen attachments

Answer 37

Platelet to platelet attachments

Question 38

What triggers amplification of aggregation into a large platelet mass?

Answer 38

Release of large quantities of ADP with thromboxane A2 (TXA2)

Question 39

Why must a platelet plug be reinforced with secondary hemostasis?

Answer 39

It is fragile and It can easily be dislodged from the vessel wall

Question 40

Which of the following is the most frequently inherited primary bleeding disorder? ## Footnote Gray platelet syndrome Bernard Soulier disease Storage pool disease Von Willebrand disease

Answer 40

Von Willebrand disease

Question 41

Which presenation are associated with von Willebrand disease? ## Footnote Heavy menstrual bleeding increased clotting with DVT formation Mucosal bleeding

Answer 41

Heavy menstrual bleeding and Mucosal bleeding

Question 42

What is the mechanism of action of aspirin?

Answer 42

Inhibition of thromboxane

Question 43

The aspirin effect lasts for

Answer 43

7 days

Question 44

Bleeding time testing gives information about ## Footnote Platelet number or count How a body responds to trauma Platelet function Heparin therapy evaluation

Answer 44

Platelet function

Question 45

What lab has largely replaced bleeding time testing?

Answer 45

Platelet function screen