Phase 1 week 3 Flashcards Preview

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Flashcards in Phase 1 week 3 Deck (71):
1

What are the three layers formed from using a centrifuge of the blood?

The haematocrit = 45%
the buffy coat
the plasma = 55%

2

what is contained within the plasma?

proteins
enzymes
nutrients
waste
hormones
gases

3

What are the functions of proteins in the plasma?

reserve supply of amino acids for cell nutrition - can be broken down by macrophages
carriers for other molecules
act as weak acids to maintain slightly basic pH
involved in the coagulation cascade
distribution of fluid between blood and tissue fluid- colloid osmotic pressure

4

What is the most abundant electrolyte in the plasma?

sodium ions which amount for most of the blood's osmolarity

5

What is another name for white blood cells?

leukocytes

6

What are platelets made from?

small fragments of bone marrow

7

What are the functions of platelets?

secrete vasoconstrictors
form temporary platelet plugs to stop bleeding
secrete procoagulants
dissolve blood clots when they are no longer needed
digest and destroy bacteria
secrete cytokines

8

What are the main functions of red blood cells?

to pick up oxygen from the lungs and deliver them to tissues elsewhere
to pick up CO2 from the tissues and unload it in the lungs

9

What is another name for red blood cells?

eryhtrocytes

10

What is the structure of red blood cells?

disk shaped cell with thick rim and sunken centre
plasma membrane has glycoproteins and glycolipids that determine blood type
spectin and actin proteins give membrane resilience and durability

11

What are the advantages of the structure of RBCs?

they can stretch, bend and fold as they squeeze through small blood vessels and spring back to shape

12

Why are RBCs incapable of aerobic respiration?

They don't contain mitochodria

13

What is the advantage of RBCs not containing mitochondria?

They can't consume the oxygen that they are transporting

14

What is the advantage of the biconcave disk shape?

Greater ratio of surface area to volume to allow gases to diffuse quickly

15

What proportion of an RBC is haemoglobin?

33%

16

why can RBCs not repair themselves?

they don't contain ribosomes

17

How long do circulating RBCs live for/

120 days

18

what is haematopoiesis?

the production of the formed elements of the blood

19

What are haematopoietic tissues?

The tissues where blood is produced

20

What is the earliest haematopoietic tissue?

the yolk sac

21

What is another name for a multipotent haematopoietic stem cell?

haemocytoblast

22

What do common myeloid progenitor cells differentiate into?

megakarycytes
erythrocytes
mast cells
myoblasts

23

What do megakaryocytes differentiate into?

thrombocytes (platelets)

24

What do myoblasts differentiate into?

basophils
neutrophils
eosinophils
monocytes

25

what do monocytes differentiate into?

dendritic cells
macrophages

26

What do common lymphoid progenitor cells differentiate into?

natural killer cels
small lymphocytes

27

what do small lymphocytes differentiate into?

B lymphocytes and T lymphocytes

28

What can B lymphocytes differentiate into

plasma cells

29

In what order are RBCs formed? (in terms of stem cells)

haemocytoblast
pro erythroblast
erythroblast
normoblast
reticulocyte
erythrocyte

30

which cells have receptors for erythropoietin?

proerythroblasts

31

how many RBCs are produced each day?

10 to the power of 12

32

how many RBCs are produced from a single proebrythroblst ?

16

33

where is EPO produced?

90% kidney
10% liver

34

What induces the production of EPO?

hypoxia

35

How is haemostasis achieved after wounding?

Immediate vasoconstriction to slow blood flow and reduce exsanguation
break in the epithelial barrier leads to recruitment of platelets to form an occlusive plug
platelets release serotonin which is a vasoconstrictor
platelets are activated by the sub endothelial matrix and each other

36

What is the receptor on platelets for collagen?

Glycoprotein Ia/IIa complex

37

What is the receptor on platelets for von Willebrand's factor and thrombin?

Glycoproteun Ib/IX complex

38

What is the receptor for fibrinogen and vWF?

Glycoprotein IIb/IIIa complex

39

What happens when platelets are activated?

Convert from compact to disk to a sphere
surface receptors become activated
cytoplasmic granules secrete their contents

40

What is the result of the activation of platelets?

mediation and reinforcement of aggregation and adhesion, promotion of further activation

41

What activates the intrinsic pathway?

Activated platelets

42

What activates the extrinsic pathway?

Exposed subendotheial tissue

43

What happens in the intrinsic pathway?

XII, XI, IX, VIII, X

44

What happens in the extrinsic pathway?

Tissue factor is required to convert VII to VIIa, which then activates X

45

What happens in the final common pathway?

Xa and Va cause the activation of prothrombin (II) to thrombin (IIa). This causes fibrinogen (I) to become fibrin (Ia)
XIIIa in the presence of fibrin leads to a cross-linked clot being formed

46

At what stages are calcium ions needed in the coagulation cascade?

Conversion of IX to IXa
Conversion of VII to VIIa

47

At what stages is vitamin K important?

Prothrombin, VII, IX, and X

48

What substances are involved in the regulation of the coagulation cascade?

Anti-thrombin, proteins C and S, and tissue factor pathway inhibitor

49

What causes fibrinolysis?

When the clot is no longer needed tissue plasminogen factor is released from the endothelial cells and causes plasminogen to be converted into the active plasmin.

50

what is a stem cell?

a stem cell can renew itself and differentiate into many types of cell

51

What is differentiation?

The process by which relatively unspecialised cells acquire specialised structural and / or functional features that characterise the cells, tissues or organs of the organism

52

What is the definition of stem cell potency?

The number of possible biological fates open to the cell

53

What does totipotent mean?

all fates possible (zygote)

54

what does multi / pluripotent mean?

many fates possible (embryonic / adult tissue stem cell)

55

What does bi / unipotent mean?

one or two fates open to the cell (adult tissue)

56

describe embryonic stem cells

pluripotent
able to become more than 220 types of cell in the body

57

Describe adult stem cells

multipotent or single type
able to become specialised cells within the residing tissue or specific cell type of the tissue

58

Give examples of different types of wounds

abrasion
degloving
insides
laceration
bites

59

What is the first aid for a wound?

elevate the area
direct pressure
indirect pressure
control bleeding
replace lost blood
history of bleeding problems

60

What is shock?

a clinical syndrome where tissue perfusion, and hence oxygenation, is inadequate to maintain normal metabolic function

61

What are the different types of shock?

hypovolaemic
cardiogenic
septic
spinal / neuro
anaphylactic

62

What causes hypovolaemic shock?

haemorrhage, burns, GI, sweat, dehydration

63

What causes cariogenic shock?

pump failure

64

What causes spinal / near shock?

altered / loss of vascular tone

65

What % of total blood volumes are involved in the classification of hypovolaemic shock?

40

66

What blood loss in ml relates to each classification of shock?

2000

67

What are the pulse rates of the different classifications of shock?

100, >120, >140

68

At what classification of shock does BP start to decrease?

class III

69

How does the mental status of a patient change through the classes of shock?

normal, mild anxiety, anxious, confused

70

What is the emergency treatment of hypovolaemic shock?

Airway with C-spine control
Breathing with oxygenation
Circulation with haemorrhage control
Disability
Exposure

71

Give examples of one standard safety protocols

Hand hygiene at the "5 moments" as described by WHO
care in the use and disposal of sharps
the correct use of PPE for contact with all blood, body fluids, secretions and excretions
providing care in a suitably clean environment with adequately decontaminated equipment
safe waste disposal
safe management of linen