BIOE 3020 TEST 2 UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

BIOE 3020 TEST 2 UPDATED ACTUAL QUESTIONS AND
CORRECT ANSWERS

Question:
1. what cell type is the entire vascular system lined with and why?
Answer:
endothelial cells: they do not support adhesion of platelets or adsorption of blood proteins

Question:
2. define hemostasis
Answer:
maintenance of a stable blood volume AKA stopping bleeding

Question:
3. 3 main steps of hemostasis
Answer:
1. vasoconstriction
2. platelet plug formation
3. blood coagulation

Question:
4. cellular contribution to hemostasis
Answer:
platelet plug

Question:
5. protein contribution to hemostasis
Answer:
coagulation cascade

Question:
6. give an example of a drug that affects the cellular and the protein contribution of hemostasis
Answer:
cellular: plavix protein: coumadin

Question:
7. define platelets
Answer:
- platelets are small, non-nucleated cells with a primary function of maintaining hemostasis and initiating
wound healing

Question:
8. what does the activation or damage of platelets lead to?
Answer:
the release of the granules and their contents

, Question:
9. what do the granules in platelets contain?
Answer:
bioactive signaling molecules/GROWTH FACTORS in cytoplasmic GRANULES

Question:
10. how do platelets initiate wound healing?
Answer:
growth factors

Question:
11. what does vascular damage lead to?
Answer:
exposure of sub-endothelial matrix/collagen

Question:
12. what does exposure of collagen lead to?
Answer:
- bindnig of von Willebrand Factor (vWF)
- platelet adhesion via glycoprotein Ib receptor

Question:
13. what does platelet damage lead to?
Answer:
release of granule contents (ADP, thromboxane A2, thrombin)

Question:
14. what bioactive signaling molecules are found in platelet granules? what are they and what do they do?
Answer:
ADP, thromboxane A2, thrombin
- they are platelet agonists or platelet activators: they activate other platelets
- leads to affinity modulation or increased binding affinity of the platelet integrin (glycoprotein IIb/IIIa)
that binds fibrinogen

Question:
15. define K affinity or binding affinity
Answer:
the strength of a binding interaction between receptor and ligand

Question:
16. how do platelets aggregate?
Answer:
with fibrinogen which binds to 2 platelet integrins, acting as a bridge for the clot