Week 3

Question 1

what is blood

Answer 1

suspension of cells in a solute of water, proteins and electrolytes

Question 2

what is plasma

Answer 2

anticoagulated blood, in which the cellular components have been removed

Question 3

what is serum

Answer 3

the liquid in blood that has been collected without an anticoagulant

Question 4

what is plasma

Question 5

what is the function of RBCs

Answer 5

deliver oxygen/CO2 to tissues

Question 6

what are platelets

Answer 6

thrombocytes which are cell fragments, produced when large megakaryocytes break into pieces

Question 7

what is the function of platelets

Answer 7

large role in blood clotting

Question 8

what is the function of WBC’s

Answer 8

primarily involved in immune responses

Question 9

what is endomitotic synchronous replication

Answer 9

when megakaryocytes grow until fragments come off

Question 10

what happens after damage to a blood vessel

Answer 10

immediate vasoconstriction

Question 11

what is extanguination

Answer 11

action of draining a person completely of blood

Question 12

what happens after breakage of the endothelial cell barrier

Answer 12

recruitment of platelets from circulation forming a plug

Question 13

what is platelet adhesion

Answer 13

when platelets interact with other cells, caused by collagen exposure

Question 14

what is platelet aggregation

Answer 14

when platelets interact with each other, forming clots

Question 15

what does platelet activation follow

Answer 15

stimulation by agonists such as ADP and thromboxane A2, or by direct interaction with the subendothelial matrix

Question 16

what change occurs in the platelets

Answer 16

platelets convert from a compact disc to an irregular sphere shape, and granules in the cytoplasm secrete their contents

Question 17

how is the loose plug formed

Answer 17

circulating platelets adhere to the initial layer of platelets

Question 18

what is coagulation

Answer 18

the mechanism which leads to the conversion of soluble fibrinogen to insoluble rigid polymer fibrin

Question 19

what is the clotting cascade

Answer 19

the mechanism by which fibrinogen is converted into fibrin

Question 20

what are most activated coagulation factors

Answer 20

proteolytic enzymes which in the presence of cofactors cleave other factors in an ordered sequence

Question 21

how is the intrinsic pathway activated

Answer 21

by exposed collagen and other negatively charged components of the subendothelium

Question 22

what does activation of factor XII lead to

Answer 22

sequential activation of factors XI, IX, VIII, X and prothrombin

Question 23

what leads to the activation of the extrinsic pathway

Answer 23

tissue factor complexes with factor VII leading to sequential activation of factors VII, X and prothrombin

Question 24

what do both pathways result in

Answer 24

the final common girl, where activated factor X, in association with the cofactor Va in the presence of phospholipid and calcium, converts prothrombin into thrombin

Question 25

how is fibrinogen converted into fibrin

Answer 25

thrombin splits the fibrinogen molecule and creates a polymer

Question 26

what is prothrombin time

Answer 26

a measure of the function of the extrinsic pathway

Question 27

what is the activated partial prothrombin time

Answer 27

a measure of the function of the intrinsic pathway

Question 28

how is blood coagulation modulated

Answer 28

anti-thrombin, proteins C and S and TFPI

Question 29

how does anti-thrombin modulate blood coagulation

Answer 29

inhibits the terminal proteins of the cascade, particularly factor Xa and thrombin. its activity is increased b interaction of heparin in the microvasculature and on the surface of the endothelial cells

Question 30

how do proteins C and S modulate blood coagulation

Answer 30

- protein C is a vitamin K dependent plasma protein - which inactivates cofactors Va and VIIIa and stimulates fibrinolysis - protein C is converted to its active form by interaction with thrombin - protein S acts as a cofactor for protein C

Question 31

how does TFBI modulate blood coagulation

Answer 31

tissue factor pathway inhibitor inactivates factor Xa and then TFBI/Xa complex inhibits factor VIIa within the VIIa tissue factor complex

Question 32

when does fibrinolysis occur

Answer 32

when damaged epithelium is repaired

Question 33

why must the fibrin thrombus be removed

Answer 33

to restore blood flow

Question 34

what facilitates thrombus removal

Answer 34

a fibrin splitting protease, plasmin

Question 35

what leads to the conversion of plasminogen to plasmin

Answer 35

release of tissue plasminogen activator (t-PA)

Question 36

what does release of t-PA lead to

Answer 36

conversion of plasminogen to plasmin and then clot breakdown

Question 37

what is circulating plasmin inactivated by

Answer 37

alpha2-antiplasmin

Question 38

what happens to RBC's before they leave the bone marrow

Answer 38

they shed their nuclei

Question 39

what is erythropoiesis

Answer 39

the production of RBC's

Question 40

what regulates erythropoiesis

Answer 40

erythropoietin

Question 41

what does the normal adult haemoglobin consist of

Answer 41

four polypeptide chains, 2 alpha and 2 beta

Question 42

what is the affinity for oxygen in haemoglobin like

Answer 42

in the lungs it is high, in the tissue it is low

Question 43

what is haematpoiesis

Answer 43

the development of haematopoietic elements

Question 44

what four lineages extend from the myeloid lineage

Answer 44

1. erythroid 2. megakaryocytes 3. granulocytic 4. monocytic

Question 45

what four cells extend from the lymphoid lineage

Answer 45

1. B-lymphocytes 2. T-lymphocytes 3. Natrual Killer cells 4. dendritic cells

Question 46

where is erythropoitetin synthesised

Answer 46

mainly by endothelial cells in the kidney

Question 47

what is the production of RBC's triggered by

Answer 47

tissue hypoxia

Question 48

what are the 3 primary aims of treating a wound with severe bleeding

Answer 48

- to control bleeding - minimise effects of shock - minimise risk of infection

Question 49

how should a wound with severe bleeding be treated

Answer 49

using a sterile dressing or a non-fluffy clan pad, with applied pressure

Question 50

where are most growth factors produced

Answer 50

bone marrow

Question 51

what is GMCSF

Answer 51

a growth factor for general stimulation of haemopoietic stem cells

Question 52

what is symmetric division

Answer 52

cell replication in which both daughter cells can either be identical to the parent or different, but with a more restricted potential

Question 53

what is asymmetric division

Answer 53

cell replication in which one daughter cell enters a differentiation pathway and gives rise to mature cells, while the other remains undifferentiated

Question 54

list the types of potency from most to least

Answer 54

totipotent, pluripotent, multipotent, unipotent

Question 55

what are the four types of shock

Answer 55

- obstructive - distributive - cardiogenic - hypovolemic

Question 56

what is the primary structure

Answer 56

the amino acid sequence

Question 57

what is the secondary structure

Answer 57

folded amino acid sequences forming alpha helices and beta pleated sheets

Question 58

what is the tertiary structure

Answer 58

the three dimensional folding of the polypeptide

Question 59

what is the quaternary structure

Answer 59

assembly of polypeptide subunits to form the overall functional protein