Proteolysis/Coagulation

Question 1

What is Factor IIa’s other name?

Answer 1

Thrombin

Question 2

How does pepsinogen activate into pepsin?

Answer 2

Autocatalysis due to pH

Question 3

Mechanism for pepsinogen activation

Answer 3

At lower pH, Asp becomes protonated and salt bridges are broken

Question 4

What is enteropeptidase?

Answer 4

A protease secreted in the small intenstine

Question 5

How is trypsin activated?

Answer 5

Enteropeptidase cleaves trypsinogen at Lys-6/Ile-7

Question 6

Which zymogens can trypsin activate?

Answer 6

Chymotrypsinogen, procarboxypeptidase, and proelastase

Question 7

Four forms of chymotrypsin

Answer 7

Chymotrypsin -> pi-chymotrypsin -> delta-chymotrypsin -> alpha-chymotrypsin

Question 8

What is a secondary safety mechanism against trypsin activation?

Answer 8

Pancreatic Trypsin Inhibitor

Question 9

What does alpna-1 antitrypsin inhibit?

Answer 9

Elastase

Question 10

What number is tissue factor?

Answer 10

Factor 3

Question 11

What does thrombin stimulate in the cascade?

Answer 11

Factors VIII and V

Question 12

What does Protein C inactivate?

Answer 12

Factors V and VIII

Question 13

Which final factor crosslinks fibrin strands to strengthen the clot?

Answer 13

Factor XIIIa

Question 14

Intrinsic to Extrinsic Pathway: Factors XII, IX, X can activate…

Answer 14

Factor VII

Question 15

How does Factor XIIIa work?

Answer 15

It’s a transglutaminase. Crosslinks glutamine and lysine sidechains

Question 16

What serves as a carrier for Factor VIII?

Answer 16

von Willebrand Factor

Question 17

What does vWF serve as a link between?

Answer 17

platelet surface glycoproteins and exposed ECM

Question 18

What does kallikrein cleave to downregulate the clotting process?

Answer 18

Active factor XII

Question 19

What activates Protein C?

Answer 19

thrombin

Question 20

What is AT3?

Answer 20

Antithrombin III; serine protease inhibitor

Question 21

AT3 inhibits…

Answer 21

thrombin, XIIa, XIa, IXa, and Xa

Question 22

What enhances the rate of thrombin-AT3 complex formation to inhibit thrombin?

Answer 22

Heparin

Question 23

What activates pasminogen into plasmin?

Answer 23

Tissue Plasminogen Activator

Question 24

What does plasmin do?

Answer 24

Cleaves fibrin and dissolves the clot

Question 25

Four factors requiring Ca2+ and phospholipid?

Answer 25

II, IX, X, VII

Question 26

Hemophilia A is a deficiency of…

Answer 26

Factor VIII

Question 27

Hemophilia B is a deficiency of…

Answer 27

Factor IX