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A&p2 > Blood > Flashcards

Blood Flashcards

1
Q

Conducting system

A

Blood vessels

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2
Q

Functions of cardiovascular system

A

■ To transport materials to and from cells:
■ oxygen and carbon dioxide
■ nutrients
■ hormones
■ immune system components
■ waste products

■ Maintain Homeostasis

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3
Q

🩸 Contains cells suspended in a fluid called…

A

Plasma

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4
Q

Tissue type

A

Connective tissue

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5
Q

5 functions of 🩸

A

• Transport of dissolved substances
• Regulation of pH and ions
• Restriction of fluid losses at injury sites
• Defense against toxins and pathogens
• Stabilization of body homeostasis
-regulation of pH, osmotic pressure, and temp (removes excess heat)

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6
Q

Plasma

A

-(more than 90% of plasma is) Water
- Dissolved plasma proteins
- Is similar to, and exchanges fluids with, interstitial fluid
- Is matrix of formed elements
-makes up 50-60% of blood volume

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7
Q

3 types of formed elements

A

1) Red blood cells (RBCs) or erythrocytes:
■ transport oxygen
2) White blood cells (WBCs) or leukocytes:
■ part of the immune system
3) Platelets:
■ cell fragments involved in clotting

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8
Q

Hemopoiesis/hematopoiesis

A

■ Process of producing formed elements
■ By myeloid and lymphoid stem cells

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9
Q

Characteristics of blood

A

■ 38°C (100.4°F) is normal temperature
■ High viscosity
■ Slightly alkaline pH (7.35–7.45)

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10
Q

Whole 🩸

A

plasma (55%) and formed elements (mostly RBCs (45%))

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11
Q

Serum

A

Plasma w/o its clotting capability (w/o fibrinogen and other clotting factors)

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12
Q

Interstitial fluid (IF)

A

same as plasma but with about 25% less protein; it is found in
the interstitium

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13
Q

Lymph

A

same as interstitial fluid except it is found in lymphatic vessels

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14
Q

🩸volume

A

■ Blood volume (liters) = 7% of body weight (kilograms):
■ adult male: 5 to 6 liters
■ adult female: 4 to 5 liters

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15
Q

3 classes of plasma proteins

A

■ Albumins (60%)
■ Globulins (35%)
■ Fibrinogen (4%)

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16
Q

Albumins

A

■ Are synthesized by the liver
■ Contribute to oncotic pressure
■ Have a buffering potential
■ Transport substances:
■ fatty acids
■ bilirubin
■ thyroid hormones
■ steroid hormones

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17
Q

Globulins

A

• Antibodies, also called immunoglobulins or Gamma Globulins
-Are synthesized by competent B lymphocyte plasma cells

• Transport globulins (small molecules):
-hormone-binding proteins
-metalloproteins
-apolipoproteins (lipoproteins)
-steroid-binding proteins
-Are synthesized by the liver

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18
Q

Fibrinogen

A

■ Molecules form clots (inactive clotting protein)
■ Produce long, insoluble strands of fibrin
■ Are synthesized by the liver
■ There are also small amounts of other clotting factor proteins

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19
Q

Serum

A

■ Liquid part of a blood sample:
■ in which dissolved fibrinogen has converted to solid fibrin
■ Remove fibrin and clotting factors
■ Ca2+ also removed

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20
Q

Solutes

A

■ Include:
■ Non-Protein Sources of Nitrogen (NPNs)
■ Nutrients
■ Electrolytes

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21
Q

Non-protein nitrogen sources (NPN)

A

-Include:
-Urea - a metabolic waste produced from deamination of amino acids
-Uric Acid - a metabolic waste produced from the catabolism of nucleic acids
-Creatinine - a metabolic end product of creatine and creatine phosphate

-excreted by kidneys
-kidney disease is often indicated by elevated NPNs

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22
Q

Nutrients

A

■ Include:
■ Monosaccharides - mainly glucose
■ Amino Acids
■ Fatty Acids
■ Lipoproteins (chylomicrons, HDL, LDL, IDL, VLDL)
■ Vitamins

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23
Q

Electrolytes

A

■ Include:
■ Na+ - major regulator of osmotic tone
■ Cl –
■ Ca 2+
■ Mg 2+
■ PO4 3-
■ SO4 2-
■ HCO3 –
■ K+

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24
Q

Measuring RBCs

A

■ Red blood cell count:
■ reports the number of RBCs in 1 microliter whole blood

■ Hematocrit (packed cell volume, PCV):
■ percentage of RBCs in centrifuged whole blood

■ Buffy coat – The thin layer of white blood cells and platelets above the packed RBCs

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25
Q

Normal 🩸 counts

A

■ RBC:
■ male: 4.5–6.3 million
■ female: 4.2–5.5 million

■ Hematocrit (%):
■ male: 40–54
■ female: 37–47

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26
Q

RBC

A

-Small and highly specialized disc

-Thin in middle and thicker at edge (biconcave)

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27
Q

Importance of RBC shape and size

A

-High surface-to-volume ratio:
-quickly absorbs and releases CO2

-Discs bend and flex entering small capillaries:
-7.8 µm RBC passes through 4 µm capillary

-Discs form stacks:
-smoothes flow through narrow blood vessels

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28
Q

Why is there no nucleus or mitochondria in RBCs?

A

The nucleus is also not required as a mature RBC does not divide.

Mitochondria is absent so that oxygen is not utilised by the RBC and all the oxygen is transported to target areas

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29
Q

Lifespan of RBCs

A

■ Lack nuclei, mitochondria, other organelles
■ Suffer wear and tear in the cardiovascular system
■ Live about 120 days

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30
Q

Hemoglobin (Hb)

A

■ Protein molecule, transports respiratory gases
■ Normal hemoglobin (adult male):
■ 14–18 g/dl whole blood

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31
Q

Hemoglobin structure

A

■ ______________ quaternary structure
■ 4 globular protein subunits (each similar to myoglobin) :
■ 2 alpha chains and 2 beta chains globular
■ These globular subunits are what binds CO2
■ each with 1 molecule of heme
■ each heme contains 1 iron ion which can bind 1 O2 molecule

■ Iron ions easily:
■ associate with oxygen (oxyhemoglobin)
■ or dissociate from iron compounds (deoxyhemoglobin)

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32
Q

Reversible CO2 transport (at lungs)

A

■ HbCO2 Hb + CO2
■ reaction occurs at the lungs where the PCO2 is low

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33
Q

Reversible O2 transport (at tissues)

A

■ HbO2 Hb + O2
■ Reaction occurs at the tissues where the PO2 is low
■ the reaction is also enhanced by:
■ ­ Body temperature
■ ­ P CO2
■ ¯ pH
■ ¯ PO2

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34
Q

Carbaminohemoglobin

A

■ With low oxygen (peripheral capillaries):
■ hemoglobin releases O2 into surrounding tissues
■ binds carbon dioxide and carries it to lungs

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35
Q

Reversible CO2 Transport (at tissues)

A

■ The binding of O2 and CO2 are reversible and appropriate:
■ Hb + CO2 HbCO2 ​​​​​ ​​​​​​ (Carbamino Hb)
■ reaction occurs at the tissues, where the PCO2 is high

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36
Q

Reversible O2 Transport (at lungs)

A

■ Hb + O2 HbO2 (Oxy hemoglobin)
■ Reaction occurs at the lungs where the PO2 is high

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37
Q

Carbon monoxide

A

■ O2 competes with CO (carbon monoxide) which has a higher affinity for Hb then O2
■ Hb + CO HbCO

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38
Q

Carboxyhemoglobin

A

Blocker of O2 transport

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39
Q

Anemia

A

■ Hematocrit or hemoglobin levels are below normal

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40
Q

Recycling RBCs

A

■ 1% of circulating RBCs wear out per day:
■ about 3 million RBCs per second

■ Macrophages of liver, spleen, and bone marrow:
■ monitor infections (tissue homeostasis, wound/bone healing liver inflammation)
■ engulf RBCs before membranes rupture (hemolyze)

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41
Q

Hemoglobinuria

A

Hemoglobin and its breakdown products in urine due to excess hemolysis in blood stream

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42
Q

Hematuria

A

whole red blood cells in urine due to kidney or tissue damage

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43
Q

Phagocytes break hemoglobin into components:

A

■ globular proteins to amino acids
■ heme to biliverdin

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44
Q

Iron recycling

A

■ Large quantities of free iron are toxic

■ Iron is bound to:
■ transport proteins (transferrin)
■ storage proteins (ferritin and hemosiderin) in muscle, liver and spleen

■ Transported back to the bone marrow by transferrin

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45
Q

Breakdown of biliverdin

A

■ Biliverdin (green) is converted to
bilirubin (yellow)

■ Bilirubin is:
■ excreted by liver (bile)
■ jaundice is caused by bilirubin buildup
■ converted by intestinal bacteria to urobilin (yellow)
■ urobilin is reabsorbed in the blood and then excreted by the liver
■ Any remaining urobilin is converted to stericobilin which gives feces its brown color

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46
Q

RBC maturation- erythropoiesis

A

■ Red blood cell formation
■ Occurs only in red bone marrow (myeloid tissue)
■ Stem cells mature to become RBCs

47
Q

Hematopoietic stem cells (hemocytoblasts)

A

■ Stem cells in bone marrow divide to produce:
■ myeloid stem cells:
■ become RBCs, ​some WBCs

■ lymphoid stem cells:
■ become lymphocytes

48
Q

Stages of RBC maturation

A

■ Myeloid stem cell
■ Proerythroblast
■ Erythroblasts
■ Reticulocyte
■ Mature RBC
■ Takes about 15 days

49
Q

Building RBCs require:

A

■ amino acids
■ iron
■ vitamins B12, B6, and folic acid

50
Q

Pernicious anemia

A

■ Low RBC production
■ Due to unavailability of vitamin B12 due to:
■ B12 deficiency
■ lack of intrinsic factor
■ absorption problem

51
Q

Stimulating hormones

A

■ Erythropoietin (EPO)

■ Also called erythropoiesis-stimulating hormone:
■ Stimulates both
■ Rate of stem cell division (ten fold)
■ Rate of Hb production (maturation)
■ secreted mostly from the kidneys when oxygen in the tissues of the kidneys is low (hypoxia)
■ due to disease or high altitude

■ EPO enters the blood and is transported to myeloid tissues and acts to
■ Increase hemocytoblast proliferation and
■ directs them toward increased erythropoiesis
■ Stimulated by testosterone

52
Q

Classification of anemias

A

■ A. Congenital - Inherited
■ B. Hemolytic - marked by excessive RBC destruction
■ C. Aplastic - red marrow shutdown
■ D. Hemorrhagic - excessive blood loss
■ E. Nutritional - due to dietary deficiencies

53
Q

Congenital anemia

A

■ are inherited due to genetic mutations and include:
■ Sickle cell
■ a and b Thalassemias

■ Sickle cell Anemia
■ Due to a point mutation in the B-globin gene
■ Causes hemoglobin - form long inflexible chains when O2 is low
■ Long inflexible cells clog arteries
■ More common in people of African decent
■ helps resistance to malaria

■ a and b Thalassemias
■ Deficient synthesis of hemoglobin
■ More common in people of Mediterranean decent

54
Q

Hemolytic anemias

A

■ marked by excessive RBC destruction
■ Fetal hemolytic disease (erythroblastosis a Rh incompatibility)
■ Malaria (protozoal parasite)
■ Gram-positive bacteria as in Streptococcal Disease

55
Q

Aplastic anemias

A

■ bone marrow shutdown caused by:
■ exposure to toxic chemicals (chloramphenicol, a broad-spectrum antibiotic)

■ Radiation exposure
■ Hypersensitivity reactions to drugs
■ All cell lines affected
■ Anemia; clotting and immunity defects
■ Treated short-term with transfusions; long-term with transplanted stem cells

56
Q

Hemorrhagic anemia

A

■ Blood loss rapid (e.g., stab wound)
■ Treated by blood replacement

■ Chronic hemorrhagic anemia
■ Slight but persistent blood loss
■ Hemorrhoids, bleeding ulcer
■ Primary problem treated

57
Q

Nutritional anemia

A

■ Most common
■ Associated with vitamin deficiencies
■ Most common are:
■ Iron Deficiency Anemia
■ Pernicious Anemia
■ Folic Acid Anemia

58
Q

Iron deficiency

A

■ cells are microcytic (small) (¯ MCV)
■ cells are hypochromic (¯ MCH) (pale in color)
■ females of reproductive age are at highest risk;
■ need Fe2+ due to menstrual loss
■ Iron supplements to treat

59
Q

Pernicious Anemia

A

■ Vitamin B12 deficiency
■ cells are macrocytic (large)
■ Cells have fragile membranes
■ Patients also develop a thick, beefy tongue

■ Patients also develop neurologic S & S including:
■ Confusion
■ Disorientation
■ forgetfulness

■ Need Vit. B12 (by injection or nasal gel)

60
Q

Folic acid anemia

A

■ same S & S as pernicious, but without neurologic S&S
■ Also essential in first trimester women for fetus CNS development
■ Need folic acid

61
Q

Renal anemia

A

o Lack of EPO
o Often accompanies renal disease
o Treated with synthetic EPO

62
Q

Reticulocytes

A

■ As myeloid stem cell transforms
■ 1.Ribosomes synthesized
■ 2.Hemoglobin synthesized; iron accumulates
■ 3.Ejection of nucleus; formation of reticulocyte (young RBC)

■ Normal Reticulocyte number = .5-2% of total RBC
■ Reticulocyte count indicates rate of RBC formation

63
Q

WBCs

A

■ Also called leukocytes
■ Do not have hemoglobin
■ Do have nuclei and other organelles

64
Q

WBC functions

A

■ Defend against pathogens
■ Remove toxins
■ Attack abnormal cells

65
Q

WBC movement

A

■ Most WBCs in:
■ connective tissue proper
■ lymphatic system organs

■ Small numbers in blood:
■ 5000 to 11000 per microliter

66
Q

Circulating WBCs

A
  1. Migrate out of bloodstream
  2. Have amoeboid movement
  3. Attracted to chemical stimuli (positive chemotaxis)
  4. Some are phagocytic:
    ■ neutrophils, eosinophils, and monocytes
67
Q

5 types of WBCs

A

A. Granulocytes
1. Neutrophils
2. Eosinophils
3. Basophils

B. Agranulocytes
1. Monocytes
2. Lymphocytes - Both B and T Lymphs

• Decreasing abundance in blood. Never let monkeys eat bananas

68
Q

Neutrophils

A

-Also called polymorphonuclear leukocytes
50–70% of circulating WBCs (12-14 um in diameter) (called “polymorphs” or “polys”)

-Pale cytoplasm has numerous small, purple granules with:
■ lysosomal enzymes
■ bactericides (hydrogen peroxide and superoxide)

-Mature are multilobed, polymorphic nucleus; (resembles Beads on a string) – Called segs (Segmented nucleus)

-Immature neutrophils are called Bands
■ their nucleus is not fully segmented (looks like a band)

-Increased bands suggests active infection

69
Q

Neutrophil Action

A

■ Very Aggressive, first to attack “antibody marked” bacteria
​and increase in number
■ Engulf pathogens
■ Digest pathogens
■ Release prostaglandins and leukotrienes
■ Form pus

70
Q

Degranulation

A

■ Removing granules from mast cells
■ caused by fusion with lysosomes

■ Occurs in Granulocytes, mast cells and some lymphocytes

■ Defensins:
■ peptides from lysosomes
■ attack pathogen membranes

71
Q

Eosinophil

A

■ Also called acidophils
■ 2–4% of circulating WBCs (12-14 um in diameter)
■ contain Red granules.
■ Bi-lobed nucleus
■ Phagocytic microphage
■ Attack large parasites and “antibody marked” objects

■ Excrete toxic compounds:
■ nitric oxide
■ cytotoxic enzymes

72
Q

Eosinophil actions

A

■ Are sensitive to allergens
■ Control inflammation with enzymes that counteract inflammatory effects of neutrophils and mast cells
■ Numbers increase in allergy, asthma, invasive parasitic disease, eosinophilic gastroenteritis

73
Q

Basophils

A

■ Are type of WBC (least common type of granulocyte)

■ bilobed nucleus most often not visible due to large numbers of large, purple granules.
■ Are less than 1% of circulating WBCs
■ Accumulate in damaged tissue
■ non phagocytic (8-10) um in diameter
■ Rare, because once formed they leave the blood and become similar to mast cells in Connective Tissue.

74
Q

Basophil actions

A

■ Release histamine:
■ dilates blood vessels

■ Release heparin:
■ prevents blood clotting

■ Release chemotactic factors:
■ inflammatory promoters

75
Q

Monocytes

A

■ 2–8% of circulating WBCs (15-25 um in diameter)
■ Are large and spherical with an indented nucleus
■ Enter peripheral tissues and become phagocytic macrophages

76
Q

Macrophage actions

A

■ Engulf large particles and bacteria
■ crucial against viruses, intracellular bacterial parasites, and chronic infections

■ Secrete substances that attract immune system cells and fibroblasts to injured area
■ Activate lymphocytes to mount an immune response

77
Q

Lymphocytes

A

Responsible for defenses in immune response

■ 20–30% of circulating WBCs
■ 8-10 um in diameter but vary in size with small lymphs averaging 6-9 um and large lymphs 10-14um
■ large, round nucleus that takes up most of the cell
■ small amount of blue cytoplasm
■ Migrate in and out of blood

■ Mostly in connective tissues and lymphatic organs
■ non phagocytic

78
Q

2 classes of lymphocytes

A

-T cells
-B cells

79
Q

T-cells

A

■ 80% T-Lymphs
■ Cell-mediated immunity (CMI) - Lymphokine production
■ Attack foreign cells

80
Q

B cells

A

■ 20% B-Lymphs
■ responsible for humoral or Antibody Mediated Immunity (AMI) Differentiate into plasma cells
■ Synthesize antibodies
■ Tend to increase in number in acute viral infection or in lymphocytic leukemia

81
Q

RBCs: WBCs ratio

A

1000: 1

82
Q

Most numerous WBC and role

A

Neutrophil- engulfs bacteria

83
Q

WBC production

A

■ All blood cells originate from hemocytoblasts:
■ which produce myeloid stem cells and lymphoid lymphocyte cells

84
Q

Myeloid stem cells

A

■ Differentiate into progenitor cells:
■ which produce all WBCs except lymphocytes

85
Q

Lymphopoiesis

A

Production of lymphocytes by lymphoid progenitor cells

86
Q

Lymphopoiesis

A

Production of lymphocytes by lymphoid progenitor cells

87
Q

WBC development

A

■ WBCs, except monocytes:
■ develop fully in bone marrow

■ Monocytes:
■ develop into macrophages in peripheral tissues

■ Granulocytes stored in bone marrow
■ 3 times more WBCs produced than RBCs
■ Shorter life span; die fighting microbes
■ Progression of agranulocytes differs
■ Monocytes – live several months
■ Lymphocytes – live few hours to decades

88
Q

4 colony- stimulating factors (CSFs)

A

■ Hormones that regulate blood cell populations:

1.​M-CSF:
■ stimulates monocyte production

2.​G-CSF:
■ stimulates granulocyte production
■ neutrophils, eosinophils, and basophils

3.​GM-CSF:
■ stimulates granulocyte and monocyte production

4.​Multi-CSF:
■ stimulates production of granulocytes, monocytes, platelets, and RBCs

89
Q

Platelets

A

■ Cell fragments involved in human clotting system
■ Nonmammalian vertebrates have thrombocytes (nucleated cells)

90
Q

Platelet circulation

A

■ Circulates for 9–12 days
■ Are removed by plateletpheresis
■ many are reserved for emergencies

91
Q

3 functions of platelets

A
  1. Release important clotting chemicals
    • Granules contain serotonin, Ca2+, enzymes, ADP, and platelet-derived growth factor (PDGF)
  2. Temporarily patch damaged vessel walls
  3. Actively contract tissue after fibrin clot formation
92
Q

Platelet production

A

■ Also called thrombocytopoiesis:
■ occurs in bone marrow

93
Q

Megakaryocytes

A

■ large bone marrow cells
■ Manufacture platelets from cytoplasm

94
Q

Hemostasis

A

■ Fast series of reactions for stoppage of bleeding
■ Requires clotting factors, and substances released by platelets and injured tissues

95
Q

3 steps of hemostasis

A

1) vascular phase

2) platelet phase

3) coagulation phase

96
Q

2 steps of vascular phase

A
  1. Pain reflexes and direct injury to vascular cause smooth muscle and endothelial cells cause both of them to contract:
    • expose basal lamina to bloodstream
    • Restrict blood flow
  2. Endothelial cells release:
    ■ chemical factors:
    ■ ADP, tissue factor, and prostacyclin
    ■ local stimuli:
    ■ endothelins
    ■ stimulate smooth muscle contraction and endothelial cell division
97
Q

Platelet phase

A

■ Begins within 15 seconds after start of vascular spasm

■ Platelet adhesion (attachment):
■ to sticky endothelial surfaces
■ to basal laminae
■ to exposed collagen fibers via plasma protein von Willebrand factor

■ Platelet aggregation (stick together):
■ forms platelet plug
■ closes small injuries

98
Q

Platelet plug: size restriction

A

■ Two mechanisms limit clot size
■ Swift removal and dilution of clotting factors
■ Inhibition of activated clotting factors

■ Prostacyclin:
■ released by endothelial cells
■ inhibits platelet aggregation

■ Inhibitory compounds:
■ released by other white blood cells

■ Negative (inhibitory) feedback:
■ from serotonin by blocking ADP
■ Stops development of blood clot

99
Q

Coagulation phase

A

■ Begins 30 seconds or more after the injury
■ Blood clotting (coagulation):
■ Involves a series of steps
■ converts circulating fibrinogen into insoluble fibrin

100
Q

Blood clot

A

■ Fibrin network
■ Covers platelet plug
■ Traps blood cells
■ Seals off area

101
Q

Cascade reactions

A

■ During coagulation phase
■ Chain reactions of enzymes and proenzymes

102
Q

Coagulation

A

■ Three phases of coagulation
■ Prothrombin activator formed in both intrinsic and extrinsic pathways
■ Prothrombin converted to enzyme thrombin
■ Thrombin catalyzes fibrinogen à fibrin

103
Q

3 phase of coagulation

A

■ Phase 1
■ Extrinsic pathway:
■ outside blood stream
■ Involves Tissue factor
■ Intrinsic pathway:
■ begins with circulating proenzymes
■ within bloodstream
■ Involves Platelet factor

■ Phases 2:
■ Activation of Thrombin
■ Phases 3:
■ Formation of final clot

104
Q

Coagulation phase 1: extrinsic pathway

A

■ Very fast (seconds)
■ Damaged cells from outside the blood vessel release tissue factor (TF, Factor III)
■ TF + other compounds including Ca2+ = enzyme complex
■ Activates Factor VII-VIIa

105
Q

Coagulation phase 2: intrinsic factor

A

■ Slower (several minutes)
■ Does not require stim. From outside the vessel
■ Activation of enzymes by collagen of damaged vessel
■ Platelets release factors (e.g., PF–3)
■ Series of reactions which include factors VIII (antihemophilic factor) and IX (Christmas factor) activate Factor X
■ Requires Ca2+

106
Q

Functions of thrombin

A

■ Stimulates activation and aggregation of platelets
■ Accelerates the formation of prothrombin activator (prothrombinase)

■ forms positive feedback loop (intrinsic and extrinsic):
■ accelerates clotting

■ Also has anticoagulant and fibrolytic effects
■ Activates Plasminogen away from the clot

107
Q

Clotting: area restriction

A
  1. Anticoagulants (plasma proteins):
    - antithrombin-III – inhibits thrombin and other clotting factors
    - alpha-2-macroglobulin – inhibits thrombin
  2. Heparin – clinically used to prevent clotting
    – from basophils and mast cells
    - Speeds the activation of antithrombin-III
  3. Prostacyclin
    - Inhibits platelet aggregation
    - Opposes the action of thrombin, ADP and other factors
108
Q

Clot retraction (syneresis)

A

■ After clot has formed:
■ Platelets contract and pull torn area together and reduce the size of the wound
■ Takes 30–60 minutes
■ A fibrinous exudate is secreted (scab)

109
Q

Fibriniolysis

A

■ Slow process of dissolving blood clots:
■ thrombin and tissue plasminogen activator (t-PA):
■ activate plasminogen

■ Plasminogen produces plasmin:
■ digests fibrin strands

110
Q

Thrombus

A

clot formed inside a vessel and attached to the vessel wall

111
Q

Thrombosis

A

the formation of a clot inside a vessel

112
Q

Embolus

A

usually foreign (from outside the vascular compartment) and travels

113
Q

Embolism

A

embolus obstructing a vesse

A&p2 (28 decks)

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