Deck 9: The Platelet

Question 1

Increased DNA content in exact multiples that are contained within a single nuclear envelope defines cells that are:

A)Polyploid
B)Proliferating
C)Apoptotic
D)Differentiated

Answer 1

Polyploid

Question 2

Laboratory results for a patient indicate that the platelet count is 89 × 10⁹/L.What is likely to be observed in the peripheral blood for this patient if the platelet count is the result of increased physiological platelet destruction?

A)Megakaryocytes
B)Megakaryoblasts
C)Reticulated platelets
D)Megathrombocytes

Answer 2

Reticulated platelets

Question 3

What is the typical concentration of platelets in the blood?

A)
B)
C)
D)

Answer 3

Question 4

Nuclear replication without cytoplasmic division is defined as:

A)Asynchrony
B)Dysmyelopoiesis
C)Hematopoiesis
D)Endomitosis

Question 5

Platelets are derived from which of the following?

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

Question 6

Describe megakaryocyte development and the role of endomitosis and thrombopoietin in this process.

Question 7

Which of the following represents a normal platelet number and morphology?

A)A platelet that is 10 mcM in size with a blood concentration of 200 × 10⁹/L
B)A platelet that is 80 mcM in size with a blood concentration of 8 × 10⁹/L
C)A platelet that is 2.5 mcM in size with a blood concentration of 250 × 10⁹/L
D)A platelet that is 5 mcM in size with a blood concentration of 600 × 10⁹/L

Question 8

Which of the following cells is defined as cytoplasmic extensions that are released in groups and fragmented into individual platelets?

A)Megakaryocyte
B)Megakaryoblast
C)Thrombocyte
D)Proplatelet

Question 9

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 10

The normal reference interval for the mean platelet volume (MPV)is:

A)9-11
B)11-14 g/dL
C)150-450 * 10⁹/L
D)8-12 fL

Question 11

Which of the following criteria describes giant platelets?

A)8-12 fL in volume
B)>5 mcM in size
C)>2N in chromosome number
D)>400 × 10⁹/L in number

Question 12

The effect of thrombopoietin (TPO)on megakaryocytic cells can be described by all of the following except:

A)Promote endomitosis
B)Inhibit proliferation
C)Increase the number in the bone marrow
D)Advance the rate of maturation

Question 13

Identify the major cytokines that regulate platelet production and describe their effects on megakaryocytic cells and circulating platelets.

Question 14

During what stage of megakaryocyte development are the 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 15

Which of the following cytokines stimulate progenitor megakaryocytes to proliferate?

A)IL-6 and IL-11
B)TPO and GM-CSF
C)EPO and M-CSF
D)IL-4 and IL-10

Question 16

Which of the following describes how platelet clumping artificially alters platelet parameters?

A)Increases both the PDW and the MPV
B)Decreases both the PDW and the MPV
C)Increases the PDW and decreases the MPV
D)Decreases the PDW and increases the MPV