Deck 31: Primary Hemostasis

Question 1

Which of the following defines the strength of a selected agonist?

A) Location in which they are derived
B) Ability to induce the full range of platelet functions
C) Ability to interact with thromboxane A2
D) Speed by which the platelets become activated

Answer 1

Ability to induce the full range of platelet functions

Question 2

Which of the following substances is found in all three layers of blood vessels?

A) Fibroblasts
B) Collagen
C) Laminins
D) Glycoproteins

Answer 2

Collagen

Question 3

Formation of a blood clot on the interior surface of an intact (unsevered) vessel is referred to as:

A) Blood coagulation
B) Hemostasis
C) Thrombosis
D) Fibrinolysis

Answer 3

Thrombosis

Question 4

Which substance stored in the dense bodies is responsible for platelet activation and is involved in activation of the coagulation cascade?

A) PDGF
B) ADP
C) Calcium
D) Thrombospondin

Question 5

Which of the following substances endogenous to the dense bodies is responsible for continuous platelet activation of surrounding platelets?

A) Platelet factor 4
B) Collagen
C) ADP
D) Epinephrine

Question 6

Secondary hemostasis involves which of the following events to further hemostasis?

A) Generation of fibrin
B) Blood remains a liquid
C) Fibrinolysis occurs
D) Inhibition of platelet release reaction

Question 7

Platelets are derived from which of the following?

A) Monoblasts
B) Pronormoblasts
C) Lymphoblasts
D) Megakaryocytes

Question 8

Transient cessation of blood loss is achieved through which of the following?

A) Formation of secondary hemostatic plug
B) Fibrinolysis of established thrombus
C) Formation of primary platelet plug
D) Inhibition of thrombus formation

Question 9

Which of the following substances functions to stabilize platelet aggregates in the platelet plug?

A) PDGF
B) Thrombospondin
C) Factor V receptor
D) PF4

Question 10

All of the following are associated with shape change in platelet activation except:

A) Actin and myosin convert to a parallel arrangement from a random arrangement
B) The platelet converts to a spiked sphere appearance from a flattened disc appearance
C) Tubulin forms a circumferential band around the organelle zone and contracts
D) Organelles sequester granule contents

Question 11

Platelet adhesion to collagen and the initiation of platelet aggregation are part of:

A) Primary hemostasis
B) Secondary hemostasis
C) Blood coagulation inhibition
D) Fibrinolysis

Question 12

Which of the following layers of blood vessels contains endothelial cells and is responsible for secreting procoagulant proteins to maintain tissue repair?

A) Tunica adventitia
B) Tunica intima
C) Tunica media
D) Basement membrane

Question 13

After a blood vessel injury, which of the following initiates hemostasis?

A) Endothelial communication
B) Platelet function inhibition
C) Vasoconstriction
D) Vasodilation

Question 14

The formation of thromboxane A2 in the activated platelet:

A) Is needed for platelets to adhere to collagen
B) Assists in the secretion of granule contents
C) Requires the enzyme cyclo-oxygenase
D) Requires von Willebrand factor

Question 15

Which of the following defines the circulatory system's ability to maintain the blood as a fluid within the blood vessels and to prevent excessive blood loss upon injury?

A) Clot retraction
B) Hemostasis
C) Coagulation
D) Thrombosis

Question 16

All the following are considered major players in coagulation except:

A) Platelets
B) Blood vessels
C) Heparan
D) Plasma procoagulant proteins

Question 17

Sequential activation of plasma procoagulant proteins that induce the formation of insoluble blood proteins occurs in which phase of coagulation?

A) Formation of primary platelet plug
B) Formation of secondary hemostatic plug
C) Fibrinolysis of existing hemostatic plugs
D) Inhibition of primary and secondary hemostatic plug formation

Question 18

The structures of different blood vessels are similar, but the functions are distinct. Which blood vessels serve as the major site of regulation of vascular permeability?

A) Arterioles
B) Venules
C) Capillaries
D) Lumen

Question 19

What is the first step in coagulation that occurs after vascular trauma?

A) Vasoconstriction at the site of injury
B) Platelet adhesion to collagen
C) Platelet activation and shape change
D) Platelet aggregation to more platelets

Question 20

Which of the following acts as a transport portal for granules to move from the organelle zone to the membrane zone?

A) Open canalicular system
B) Dense tubular system
C) Membrane glycoproteins
D) Endoplasmic reticulum

Question 21

Explain the biochemistry involved in platelet function.

Question 22

During what stage of megakaryocyte development are platelets released into the circulation?

A) Between stages III and IV
B) At the end of stage II
C) During the cycling phase
D) At the point of proplatelet formation

Question 23

On average, how long does a platelet live in the peripheral circulation?

A) 6 hours
B) 120 days
C) 5 days
D) 10 days

Question 24

Which platelet ultrastructural zone has the functions of secretion, storage, and lipid metabolism?

A) Peripheral
B) Structural
C) Organelle
D) Membrane zone

Question 25

Correlate blood vessel histology to vessel type and function in hemostasis.

Question 26

The major platelet plasma membrane receptor for fibrinogen is:

A) GPIc/IIa
B) GPIbβ
C) GPIIb/IIIa
D) GPIb/IX/V

Question 27

Which of the following is responsible for the platelet surface negative charge and is found on the surface membrane of the interior channels?

A) Dense tubular system
B) Open canalicular system
C) Submembranous cytoskeleton
D) Glycocalyx

Question 28

Which of the following is a role of platelets in secondary hemostasis?

A) To secrete factors needed for serine protease activation
B) To initiate cross-linking of the fibrin monomers
C) To activate thrombin
D) To initiate contact activation

Question 29

Beginning with the trauma, what is the sequence of events that leads to the formation of a clot (thrombus)?

Question 30

Which function of the endothelial cell keeps cells and macromolecules in vessels and allows nutrient and gas exchange?

A) Blood-borne antigens processing
B) Tissue factor production
C) Nitric oxide production
D) Blood/tissue barrier

Question 31

Which of the following best describes the role of platelet factor 4?

A) Stimulates platelet aggregation
B) Contributes to fibrin formation
C) Neutralizes heparin
D) Acts as a mitogenic factor

Question 32

How does the vascular system contribute to hemostasis?