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Flashcards in Blood Deck (103):
1

Why is it important that blood has a high heat capacitance?

Thermoregulation

2

How many liters of blood are in men (on average)? Women?

5 liters for women
5.5 liters for men

3

What are the three separate layers of a blood sample that are seen when spun out? What percent of the blood are each?

Blood layer -42%
Buffy white coat -min
Plasma -58%

4

The blood is what percent of the body weight?

7-8%

5

What are the three major categories of the components of plasma?

Water
Proteins
Other solutes

6

What the four categoeries of proteins in plasma? Which is found in highest concerntration?

Albumin**
Globuin
Fibrininogen
Regulatory protein

7

What are the three types of cells in the blood in order of their abundance?

1. RBCs
2. Platelets
3. WBCs (basophil lowest)

8

What is serum? How does this compare to plasma?

Plasma without fibrinogens and other coagulation factors

9

What is a mEq?

mM of ion multiplied by its charge

10

What is the anion gap calculation?

[Na] - ([Cl[ +[HCO3])

11

What are the primary cations in the plasma? Interstitial fluids? Intracellular fluid?

Plasma = Na
Interstitial fluid = Na
Intracellular fluid = K

12

What are the primary anions in the plasma? Interstitial fluids? Intracellular fluid?

Plasma = Cl and HCO3
Interstitial fluid = Cl and HCO3
Intracellular fluid = HPO4/proteins

13

What is the normal range of the anion gap?

8-16 mEg/L

14

What does the anion gap measure?

The anions that are not measured

15

What is the reason for looking at the anion gap?

Looks for metabolic acidosis

16

What can cause an increased anion gap?

Acidosis (DKA, lactic/salicylic acidosis)

17

What causes an increased anion gap?

[HCO3] goes down d/t increase in acids

18

Can you have a normal anion gap with acidosis?

Yes, if Cl balances out the loss of HCO3 (or vice versa)

19

How does hypoalbuminemia affect the anion gap?

Decreases anion gap d/t retention of CL and HCO3

20

What is osmolality?

osmoles of solute / Kg of solvent

21

What is an osmole?

Moles of solute times the number of ions or particles upon its dissociation in solution

22

What are the five major determinants of osmolality?

Na, Cl, HCO3, BUN, and glucose

23

The molality of plasma is higher or lower than interstitial fluid? Why?

Slightly higher because the plasma contains proteins (albumin) that cannot cross the capillary membrane

24

What is the osmotic pressure?

Pressure produced by the plasma proteins

25

What is albumin?

Transporter for FFAs, Ca, Cu, steroids, bili etc

26

Loss of albumin leads to what?

Edema

27

What is the primary cause of colloid osmotic pressure? What percent does this contribute?

Albumin--70-80% of colloid osmotic pressure

28

What percent of plasma protein is made up of albumin?

58%

29

What can cause hypoalbuminemia?

Malnutrition
Liver disease
Malabsorption

30

What can cause hypoalbuminemia?

Overhydration
Sepsis
hypoxia
Nephrotic syndrome

31

What is the function of gamma-globulins?

Immunoglobulins

32

What is the purpose of transferrin?

Binds free Fe (since free Fe is toxic)

33

Is free Fe toxic?

Yes

34

What is the function of haptoglobin?

Binds free Hb that can enter the plasma after the lysis of RBCs to transport it to the liver

35

Can Hb be excreted in the urine? Can Hb + haptoglobin?

Yes for Hb, it is small enough

No for Hb + haptoglobin

36

What happens to the HB/HP complex?

Macrophages in liver and spleen endocytose it to conserve Fe

37

What is the half-life of free haptoglobin?

5 days

38

What is half-life of haptoglobin when bound to HB?

90 minutes

39

What would happen to plasma Hb and haptoglobin levels during an episodes of increased intravascular hemolysis?

Decreased haptoglobin levels

Increased Hb levels

40

What happens to platelets when it binds collagen/ligands in the vessels?

Increases surface area through projections

41

What is the purpose of a blood smear?

Estimate the relative abundance of different cells (RBCs, WBCs, platelets etc), size,or color of RBCs

42

What is the stain used to a blood smear?

Giemsa stain

43

What is the term describing the normal color of Hb? Less colored?

Normochromic

Hypochromic

44

What is hematopoiesis?

The process by which RBCs are formed

45

What is the life span of RBCs?

120 days

46

What is the source of hematopoiesis? (where is it)

Stem cell in bone marrow

47

Are the progenitor cells from the hematopoietic stem cells differentiated?

Not really, and one stays a stem cell

48

What are the two lineages of the hematopoietic stem cell?

Lymphoid lineage
Myeloid lineage

49

How is the hematopoietic system regulated?

Whole bunch of growth factors working in a combinational fashion

50

Why is it important that the RBCs have a biconcave shape?

Increase surface area/volume ratio

Easily and reversibly deformable

51

Why is it important that RBCs are easily and reversibly deformable? What happens if they are not (like when they are older)?

Needs to pass through tiny passages in the spleen

If old, cannot, and thus endocytosed

52

What is the function of carbonic anhydrase in RBCs?

Enzyme facilitates that conversion of CO2 into HCO3

53

In what form do RBCs carry CO2?

HCO3

54

What is the primary HB type in adults?

HbA

55

What are the four chains that comprise Hb?

two alpha
two beta

56

What is the amino acid in the Hb that accepts H+ in the blood?

Histidine

57

What is erythropoietin?

Growth factor that stimulates the production of RBCs

58

In what stage of development do immature RBCs lose their nucleus?

Erythroblast stage

59

What are the four stages of RBC development?

Erythroid progenitors
Erythroblasts
Reticulocytes
Erythrocytes

60

How long do reticulocytes circulate for? An increase in this is indicative of what?

24-48 hours

Increase = increase in erythropoiesis

61

Where is erythropoietin produced?

The kidneys

62

What is the stimulus for erythropoetin synthesis?

O2 levels in the kidneys

63

What are the 5 factors that decrease O2 delivery to the kidney?

1. Low blood volume
2. Low Erythrocyte numbers
3. Low functional HB
4. poor blood flow
5. Pulmonary disease

64

Why can chronic renal failure cause anemia?

Lack of erythropoietin

65

What are the two fates of old RBCs?

Lyse in circulation

Phagocytosed by macrophages in the liver and spleen

66

What happens to the protoporphyrin ring of the broken RBCs?

Converted to Bilirubin by liver

67

What happens to the Fe in Hb?

Recycled

68

What is hematocrit?

% of total volume of RBCs per total blood volume

69

What causes high hematocrit levels?

Low?

High = Polycythemia or dehydration

Low = Anemia, overhydration, or malnutrition

70

What is the mean corpuscular (cell) volume?

Hematocrit %/RBC count

71

What is the normal ranges for MCV?

80-100 fL

72

What is the mean corpuscular Hb [c] (MCHC)?

Hb x100 / Hematocrit %

73

What is the reference range for MHCH?

33-37 g/dL

74

How can anemias be classified?

Cell size
Hb levels

75

What are platelets?

Small nucleus-free fragment of megakaryocytes

76

How long do platelets last? What organ destroys them?

10 days
liver

77

What activates platelet? What happens with activation?

When glycoproteins on the surface bind collagen and other factors at sites of injury

Activation = shape changes and secretions of clotting factors

78

Which WBC is found in the highest amount? Lowest?

Highest = PMNs
Lowest = Basophils

79

Why is are there more cations in the plasma, compared to the interstitial fluid?

[Albumin] higher

80

What to plasma [K] if there is a significant amount of cell lysis? Why is this not problematic in the body? Where is it a problem?

Increases, but kidneys handle it

It IS a problem if there is blood cell lysis during the sampling process

81

Within any one compartment in the body (e.g interstitial fluid, intracellular fluid etc) is there a slight charge, or do the cations balance the anions?

Balance

82

What can diarrhea cause the anion gap to do? How?

Increase d/t loss of HCO3

83

How can you have an acidosis without an anion gap?

If Cl goes up as much as HCO3 goes down

84

What is the formula for calculating plasma osmolality?

2 [Na] + ([BUN] /2.8) + [glucose]/18)

85

What is the range of osmolality of blood?

285-295 mOsm/kg H2O

86

Why is there a 2 coefficient in from of [Na] in the equation for determining plasma osmolality?

Account for Cl that dissolves with it

87

Why do you divide the [BUN] and glucose?

convert to milliosmoles per kg

88

What does the lymphoid lineage of cells give rise to?

T cells
B cells
NK cells

(all the lymphocytes)

89

What does the myeloid lineage of cells give rise to?

PMNs
eosinophils
monocytes
Erythrocytes

90

What are "colony forming units"?

Groups of lymphoid or myeloid progenitor cells

91

What are "blasts"?

Precursor cells of many types

92

What is the disorder where there are too many RBCs made?

Polycythemia

93

What is the half-life of reticulocytes? Why is this important?

24-48 hours.
Useful for seeing how much new RBC synthesis is occurring

94

What do kidneys produce when they sense that O2 levels are low?

Erythropoietin

95

What is HIF-alpha?

A transcription factor that is constantly synthesized

96

What happens to HIF-alpha in the presence of oxygen? What does this cause?

An enzyme adds a hydroxyl group to a Pro residue, causing VHL to target it for degradation for the proteasome

97

A decrease in oxygen levels leads to a (increase/decrease) in HIF-alpha? How?

Increase d/t decreased degradation by proteasomes

98

What happens to platelets at the end of their life?

Destroyed by liver

99

What is the process of platelet formation?

Thrombopoiesis

100

What is the chemical that is secreted constitutively by the liver and bone marrow, and stimulate megakaryocyte-progenitor cells?

TPO (thrombopoietin)

101

What are the progenitor cells that give rise to platelets?

Megakaryocyte-progenitor cells

102

What is the feedback mechanism for thrombopoiesis?

Increases in platelet numbers causes a negative feedback by binding to and degrading TPO

103

What happens to the megakaryocytes when they mature?

Spill out platelets