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Flashcards in Blood Deck (75)
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1
Q

Blood is a connective fluid made up of plasma, proteins and formed elements like…

A

Erythrocytes, Leukocytes, and Platelets

2
Q

What is a normal hematocrit reading?

A

45% RBC volume

3
Q

What are the 3 main characteristics of blood?

A

Viscosity (thicker)
Temperature ( heat generation by active skeletal m.)
Slightly alkaline ( pH between 7.35 and 7.45)

4
Q

List 6 functions of blood…

A
  • Clot to prevent blood loss
  • Combat microorganisms with immune response
  • Transport O2 from lungs to cell & CO2 from cells to lungs
  • Regulate body temperature
  • Regulate pH via buffering
  • Control water & electrolyte amount
5
Q

How does blood regulate pH via buffering?

A

haemoglobin of RBC can combine with CO2 to transport it from tissues to lungs, Hb binds H+ ions and alters pH of blood

6
Q

What is the red blood cell equation?

A

CO2 + H2O = H2CO3=H+ + HCO3

7
Q

What is the function(s) of plasma proteins?

A
  • Establish osmotic gradient between blood and interstitial fluid
  • Act as buffer systems
8
Q

What are three classes of plasma proteins?

A

Albumins, Globulins, Fibrinogens

9
Q

What is the function of albumins?

A

contribute to osmotic pressure of plasma and transport fatty acids

10
Q

What is the function of globulins?

A

thyroid binding ( binds thyroxine)
transcortin (transports ACTH and cortisol)
transferrin ( transports iron)

11
Q

What is the function of fibrinogens?

A

blood clotting

12
Q

Where are plasma proteins produced?

A

liver

13
Q

What are 2 differences between plasma and interstitial fluid?

A

concentration of dissolved proteins and levels of respiratory gases

14
Q

What is the process of production of formed elements called?

A

hematopeiesis

15
Q

What does PHSC stand for?

A

Pluripotent hematopoietic stem cell

16
Q

What does PHSC divide into?

A

PHSC, lymphoid stem cell (LSC) and colony forming unit

17
Q

What do lymphoid stem cells produce and were are they produced?

A

T cells and B cells and spleen

18
Q

What is colony forming unit -E influenced by and what does it produce?

A

Erthyropoietin, develops into reticulocytes and then erythrocytes

19
Q

What is colony forming unit-M influenced by and what does it produce?

A

Thrombopoietin, develops into megakaryocytes and then platelets

20
Q

How are RBC’s formed?

A

common myeloid progenitor cells begin synthesizing haemoglobin, after several divisons the erythroblast loses its nucleus and becomes immature reticulocyte, it then leaves bone marrow, 2-3 days later loses ER, mitochondria and ribosome’s and become mature erythrocyte (RBC)

21
Q

T or F: Production and destruction of RBC are maintained at an equal rate?

A

True

22
Q

T or F: Decreased oxygen levels cause kidney to release erythropoietin?

A

True

23
Q

How are RBC destroyed?

A

Spleen has narrow capillaries, as aged RBC move through their membranes will rupture

24
Q

T or F: Macrophages will engulf dead RBC

A

True

25
Q

What is anaemia?

A

low number of red blood cells, reduction in O2 carrying capacity

26
Q

What is a anaemic hematocrit?

A

30 % total RBC volume

27
Q

What are three main causes of anaemia?

A

decreased rate of RBC production
excessive loss of RBC
deficiency in hemoglobin of RBC

28
Q

What is nutritional anaemia?

A

dietary deficiency of a factor needed for RBC production ( ex. not enough iron or folic acid)

29
Q

What is aplastic anaemia?

A

failure of bone marrow to produce adeqaute numbers of RBC

30
Q

What is haemolytic anaemia?

A

rupture of excessive numbers of circulating RBC’s

31
Q

What happens in a foal who’s mother had haemolytic anaemia?

A

mare produces antibodies against foal’s blood type and trasnfers antibodies through milk, foal may develop anemia as mare’s antibodies destroy foal’s RBC

32
Q

What is AIHA?

A

Autoimmune haemolytic anemia, body attacks RBC, common in dogs

33
Q

What is polycythemia?

A

excess of circulating RBC’s

34
Q

What is primary polycythemia?

A

tumor-like condition of bone marrow in which RBC production proceeds at excessive, uncontrolled rate

35
Q

What is secondary polycythemia?

A

“physiological”, prolonged reduction to O2 delivery to tissues, high altitudes

36
Q

What does thrombin do?

A

converts fibrinogen to fibrin

37
Q

T or F: Serotonin inhibits platelet plug formation?

A

False

38
Q

T or F: Vascular spasm occurs at the begging of haemostasis?

A

True

39
Q

What is osmosis?

A

Movement of solvent from an area of high solvent activity to lower solvent activity through a selectively permeable membrane

40
Q

Where is haemoglobin produced?

A

Red blood cells

41
Q

T or F: HCO3 diffuses out of RBC’s and Cl- diffuses in?

A

True

42
Q

What cell type gives rise to platelets?

A

Megakaryocytes

43
Q

How are platelets produced?

A

Mature megakaryocytes shed cytoplasm, then enter circulation and gradually lose cytoplasm to produce platelets

44
Q

Where is thrombopoietin produced?

A

kidneys

45
Q

T or F: Platelets leave the blood?

A

False

46
Q

What are the main functions of platelets?

A
  • transport chemicals
  • formation of platelet plug
  • active contraction
47
Q

What is vascular spasm?

A

cutting of blood vessel wall triggers contraction of smooth muscle fibers, decreses the diameter of the injured vessel, and constriction slows blood flow to minimize blood loss

48
Q

What do endothelial cells do during a vascular spasm?

A

contract and expose underlying basement membrane to the blood stream, then release endothelin to constrict blood vessels

49
Q

T or F: Do endothelial cells become sticky during a vascular spasm?

A

True

50
Q

What is the process of platelet plug formation?

A

When blood vessel lining is injured, platelets attach to exposed collagen, they become activated and change shape and extend and release several compounds

51
Q

What does ADP do in platelet plug formation?

A

platelet aggregation and shape changes

52
Q

What does thromboxane A2 do in platelet plug formation?

A

stimulates platelet aggregation and releases ADP, and stimulates smooth muscle contractions in vessel walls enhancing vascular spasms

53
Q

What does calcium do in platelet plug formation?

A

clotting process and aggregation

54
Q

What is a key factor that limits the growth of platelet plug?

A

prostacyclin

55
Q

T of F: Vascular spasm and platelet phases begin within a few seconds of injury?

A

True

56
Q

T or F: Fibrinogen is always circulating in blood stream

A

True

57
Q

What are procoagulants?

A

clotting factors

58
Q

What are anticoagulants?

A

prevent clotting

59
Q

Where are procoagulants released from (think all but 3)

A

liver

60
Q

T or F: Calcium is invovled in every step of the clotting process?

A

True

61
Q

T or F: Vitamin K must be present in adequate amounts for liver to synthesize clotting factors?

A

True

62
Q

What is prothrombin?

A

Factor II

63
Q

What is proconvertin?

A

Factor VII

64
Q

T or F: reduction in vitamin k causes breakdown of clotting process due to lack of procoagulants?

A

True

65
Q

What is an intrinsic pathway?

A

in the blood, exposure of blood to collagen, takes 1-6 minutes to cause clotting

66
Q

What is an extrinsic pathway?

A

in liquid of blood, trauma to vessel wall, takes 15 seconds to cause clotting

67
Q

What is clot retraction?

A

Fluid is squeezed from clot (serum) reduces size of damaged area, fibroblast, smooth muscle cells and endothelial cells complete repairs

68
Q

T or F: Fibrinolysis is clot removal?

A

True

69
Q

T or F: Plasminogen converts in plasmin and degrades fibrin

A

True

70
Q

T or F: Plasminogen is activated by t-PA

A

True

71
Q

List 3 reasons why blood doesn’t clot all the time?

A

Smoothness of vessel wall
substance inside of wal
thrombomodulin

72
Q

Name two anticoagulants

A

Prostacylin and tissue plasminogen activator

73
Q

What does heparin do? and is it a pro or anti coagulant?

A

Anti, and it accelerates activation of anti- thrombin III that inhibits the production of several different procoagulants

74
Q

What does Warfarin do?

A

depress the synthesis of clotting factors by blocking the use of Vitamin K by the liver

75
Q

What are the three factors NOT released by the liver ?

A

Factor 3, 4 and 8