B4 Thrombosis and Coagulation Flashcards Preview

Phase I Medicine > B4 Thrombosis and Coagulation > Flashcards

Flashcards in B4 Thrombosis and Coagulation Deck (21):
1

What are platelets?

Irregularly shaped cells that don't have a nucleus

2

What are platelets derived from?

Megakaryocytes in the bone marrow

3

What is the life span of platelets?

5-9 days in circulation

4

What hormone is responsible for the regulation of platelet production?

Thrombopoeitin (TPO)

5

What organs produce thrombopoeitin?

Liver and Kidney

6

What happens to old platelets?

They are destroyed by macrophages in the spleen and liver

7

What are the properties of platelet reserves?

Found in spleen
Released by splenic contraction

8

What is the first step in megakaryocyte differentiation?

DNA duplication

9

True or false? Megakaryocytes can contain up to 32 copies of their DNA?

False - They can contain up to 64 copies

10

How do platelets form from megakaryocytes?

Cytoplasm budding off the membrane

11

What happens after all of the platelets have been made?

All that remains of the megakaryocyte is the cell nucleus.

12

What happens to the megakaryocyte remnants after platelet production?

The cell nucleus is destroyed by macrophages in the lung

13

How many platelets can be released from megakaryocytes?

2000-5000

14

What 3 granules do platelets contain?

Dense
Lamda
Alpha

15

What are the properties of dense granules?

Contain ADP/ ATP, Calcium and Serotonin

16

What is the function of dense granules?

Helps to stimulate aggregation

17

What is the main property of lambda granules?

Contain hydrolytic enzymes

18

What are the properties of alpha granules

Contain a bunch of clotting factors including:
Platelet factor 4
TGFB1 (Transforming growth factor B1)
PDGF (Platelet derived growth factor)
Fibronectin
vWF
Fibrogen
Coagulation factors V and XIII
B-Thromboglobulin

19

What is thromboxane A2 responsible for?

Stimulates platelet production and aggregation

20

What is Thrombospondin- 1?

Anti-angiogenesis regulator

21

What does Sphingospine - 1 - Phosphate do?

Regulates angiogenesis and immune function