Lecture 12: Blood

Question 1

Thrombin activates

Answer 1

Factor V

Question 2

Platelets

Answer 2

Derived from megakaryocytes
200-400k per microliter of blood
Enhance aggregation by release of factors, promote clot formation, retraction, and dissolution
Repair damage to endothelium by forming platelet plug

Question 3

Lymphocyte characteristics

Answer 3

Large, round, sometimes slightly indented nucleus (fills most of cell)
Variation in cell size
B-lymphocytes-precursor of plasma cells
T-lymphocytes

Question 4

Erythrocyte (RBC) characteristics

Answer 4

Numbers increase under influence of erythropoietin
Devoid of granules and ORGANELLES
Peripheral proteins include spectrin and actin

Question 5

Von willebrand factor

Answer 5

Plasma protein (released from Weibel-Palade bodies in endothelial cells) that facilitates the adherence of platelets to the walls of damaged blood vessels

Question 6

Formation of platelet plug step one

Answer 6

Platelets adhere to exposed collagen (after endothelial lining is disrupted by injury) and release contents of their secretory vesicles, including ADP, and also cause the conversion of arachidonic acid in the platelet plasma membrane to thromboxane A2, which further stimulates platelet aggregation

Question 7

Kallikrein is involved in

Answer 7

Formation of bradykinin and conversion of plasminogen to plasmin
-Can feedback and activate more Factor XII

Question 8

Prothrombin is activated by

Answer 8

Factor XII

Question 9

Intrinsic pathway

Answer 9

Typically initiated by injury to the endothelium of the blood vessel, exposing collagen. Everything necessary for it to occur is already within the blood

Question 10

RBC membrane proteins & function

Answer 10

Ankyrin- links the spectrin-actin network and the plasma membrane by binding to spectrin and a transmembrane band
Protein 4.1- link that binds spectrin-actin junctions and transmembrane protein glycophorin

Question 11

Major structural protein of RBCs

Answer 11

Spectrin

Question 12

Hemostatic sequence of events (in small vessels)

Answer 12

Constriction of smooth muscles around vessels
Constriction of vessels
Slowing of blood
Formation of platelet plug
Blood clotting (coagulation)

Question 13

Endothelial cells release

Answer 13

Prostacyclin- decreases platelet aggregation

Question 14

Vitamin K is necessary for synthesis of

Answer 14

Factors VII, IX and X

Question 15

Albumins

Answer 15

Made in liver

Exert major osmotic pressure on blood vessel walls

Question 16

BC step four

Answer 16

Reshaping of the clot by polymerization of fibrin

Question 17

Adhesion of platelets involves

Answer 17

Integrin

Question 18

Factor XII is activated when

Answer 18

When it contacts collagen in the damaged vessel wall

Question 19

Eosinophil characteristics

Answer 19

Lobulated (bilobed) nucleus
Specific granules (Major basic protein, peroxidase, cationic protein)
Respond in allergic diseases and parasitic infections
Phagocytize antibody-antigen complexes and parasites

Question 20

Factor XII converts x-y

Answer 20

Prekallikrein to kallikrein

Question 21

Basophilic granules contain

Answer 21

Vasoactive substances

• Serotonin
• Heparin (anticoagulant)
• Kallikrein (attracts eosinophils)

Question 22

Most clotting factors are synthesized in the

Answer 22

Liver

Question 23

RBC structure

Answer 23

Tetramer of two polypeptide chains

Ends of spectrin tetramers associate with short actin filaments creating spectrin-actin network

Question 24

Monocyte characteristics

Answer 24

Largest leukocytes
Eccentrically located, kidney shaped nucleus
Granular cytoplasm due to small lysosomes
Precursor of macrophages and osteoclasts

Question 25

Fibrinogens

Answer 25

Made in liver
Function in blood clotting
Target for thrombin

Question 26

Formation of platelet plug step two

Answer 26

ADP and other factors cause the platelets to aggregate, forming plug

Question 27

BC step five

Answer 27

Dissolution of fibrin clots through activation of the plasminogen activator system and the action of plasmin
-this is called fibrinolysis

Question 28

Hematoma

Answer 28

Accumulation of blood in tissues

Question 29

Neutrophil characteristics

Answer 29

Active amoeboid phagocytes
Small, numerous specific granules
Larger, less numerous azurophilic granules
Remain in circulation for 10-12 hours, live for 1-2 days after leaving circulation
Secrete a class of enzymes capable of destroying certain bacteria

Question 30

BC step two

Answer 30

Conversion of prothrombin to thrombin

Question 31

BC step three

Answer 31

Conversion of fibrinogen to fibrin by thrombin

Question 32

Basophil characteristics

Answer 32

Lobulated (bilobed) nucleus

Large, membrane bound basophilic granules

Question 33

Thromboplastin

Answer 33

Membrane-bound lipoprotein expressed at sites of cell injury

Derived from membranes of damaged cells

Question 34

Blood clot is dissolved by

Answer 34

Plasmin and t-PA

Question 35

Platelets release

Answer 35

Thromboxane- increases platelet aggregation

Question 36

Plasma

Answer 36

Blood minus the formed elements

Question 37

Serum

Answer 37

Plasma without the blood-clotting proteins

Question 38

Extrinsic pathway steps

Answer 38

Thromboplastin leads to the activation of Factor VII

Factor VII + Calcium + Thromboplastin activates Factor X

Question 39

BC step one

Answer 39

Activation of prothrombin

Question 40

Basophilic granules can produce

Answer 40

Leukotrienes

• Increase vascular permeability
• Slow contraction of smooth muscles

Question 41

Extrinsic pathway

Answer 41

Involves the formation of tissue factor (thromboplastin or Factor III)

Question 42

Major contents of Erythrocytes (RBCs)

Answer 42

Lipids
ATP
Carbonic anhydrase
Hemoglobin