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A&P II > Chapter 17 - Blood > Flashcards

Chapter 17 - Blood Flashcards

1
Q

Blood consists of ___ and ____.

A

plasma; formed elements

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2
Q

Formed elements are:

A

living blood cells suspended in plasma

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3
Q

The different formed elements in blood are:

A
  1. erythrocytes
  2. leukocytes
  3. platelets
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4
Q

Erythrocytes are

A

red blood cells

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5
Q

Leukocytes are

A

white blood cells

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6
Q

Centrifugal spinning of a blood sample in a test tube yields three layers:

A
  1. Plasma on top (~55%)
  2. Buffy coat (WBCs and platelets) (< 1%)
  3. Erythrocytes on bottom (~45%)
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7
Q

The hematocrit is:

A

The percent of blood volume that is RBCs

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8
Q

Blood colour varies with oxygen content. If it has high O2, the colour is

A

scarlet

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9
Q

Blood colour varies with oxygen content. If it has low O2, the colour is

A

dark red

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10
Q

The pH of blood is:

A

7.35-7.45

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11
Q

Blood is approximately how much of body weight?

A

~8%

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12
Q

The different functions of blood include:

A
  1. Distributing substances
  2. Regulating blood levels of substances
  3. Protection
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13
Q

Different distribution functions of blood:

A
  1. Delivering O2 and nutrients to body cells
  2. Transporting metabolic wastes to lungs and kidneys for elimination
  3. Transporting hormones from endocrine organs to target organs
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14
Q

Different regulation functions of blood:

A
  1. Maintaining body temperature by absorbing and distributing heat
  2. Maintaining normal pH using buffers
  3. Maintaining adequate fluid volume in circulatory system
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15
Q

Different protection functions of blood:

A
  1. Preventing blood loss

2. Preventing infection

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16
Q

____ and ____ initiate clot formation.

A

Plasma proteins; platelets

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17
Q

Blood plasma as over 100 dissolved solutes. The different solutes are

A
  1. nutrients
  2. gases
  3. hormones
  4. wastes
  5. plasma proteins
  6. inorganic ions
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18
Q

The most abundant solutes in the blood plasma are

A

plasma proteins

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19
Q

Plasma proteins:

A
  1. remain in blood; are not taken up by cells

2. are produced mostly by liver

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20
Q

Plasma proteins consist of:

A
  1. 60% albumin
  2. 36% globulins
  3. 4% fibrinogen
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21
Q

The different functions of albumin are:

A
  1. Substance carrier
  2. Blood buffer
  3. Major contributor of plasma osmotic pressure
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22
Q

Platelets are _____.

A

cell fragments

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23
Q

Most formed elements survive in the bloodstream for:

A

only a few days

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24
Q

Most blood cells originate in:

A

the bone marrow

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25
Q

Physical characteristics of erythrocytes:

A
  1. Biconcave shape–huge surface area relative to volume
  2. 97% hemoglobin for gas (mostly O2) transport
  3. anucleate
  4. no organelles or mitochondria
  5. contains plasma membrane protein spectrin and other proteins
  6. do not consume O2 they transport
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26
Q

ATP production in RBCs is through ___ means.

A

anaerobic

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27
Q

This plasma protein provides flexibility to RBCs to change shape.

A

spectrin

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28
Q

The hemoglobin structure consists of:

A
  1. globin

2. heme pigment

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29
Q

Globin is composed of:

A

2 alpha and 2 beta chains (4 polypeptide chains)

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30
Q

____ is bonded to each globin chain in hemoglobin.

A

heme pigment; gives blood its red colour

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31
Q

Heme and hemoglobin’s functions:

A
  1. heme has a central iron atom that binds one O2

2. each hemoglobin molecule can transport four O2

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32
Q

Each RBC contains approximately ____ hemoglobin molecules.

A

250 million

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33
Q

O2 loading in lungs produces:

A

oxyhemoglobin (ruby red)

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34
Q

O2 unloading in tissues produces:

A

deoxyhemoglobin (reduced hemoglobin) (dark red)

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35
Q

When CO2 loads in tissues:

A

20% of CO2 in blood binds to hemoglobin, which produces carbaminohemoglobin

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36
Q

Blood cells form in _____.

A

red bone marrow

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37
Q

Blood cell formation in red bone marrow is composed of:

A
  1. reticular connective tissue

2. blood sinusoids

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38
Q

Hematopoiesis:

A

blood cell formation

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39
Q

Blood cell formation is found in:

A
  1. axial skeleton
  2. girdles
  3. proximal epiphyses of humerus and femur
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40
Q

New blood cells in hematopoiesis enter:

A

blood sinusoids

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41
Q

Aspects of hematopoietic stem cells (hemocytoblasts) in hematopoiesis:

A
  1. they give rise to all formed elements
  2. hormones and growth factors push cell toward specific pathway of blood cell development
  3. committed blood cells can not change
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42
Q

The stages of erythropoiesis:

A
  1. myeloid stem cell is transformed into proerythroblast
  2. in 15 days proerythroblast develops into basophilic erythroblast
  3. then into polychromatic erythroblast
  4. then orthochromatic erythroblast
  5. then reticulocytes
  6. reticulocytes then enter bloodstream, and in 2 days become mature RBC
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43
Q

In erythropoiesis, as myeloid stem cell transforms:

A
  1. ribosomes are synthesised
  2. hemoglobin is synthesised; iron accumulates
  3. nucleus is ejected; reticulocyte is formed (young RBC)
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44
Q

After reticulocyte is formed from erythropoiesis:

A

reticulocyte ribosomes are degraded, then the erythrocyte becomes mature

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45
Q

Reticulocyte count indicates:

A

rate of RBC formation

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46
Q

Too few RBCs leads to:

A

tissue hypoxia

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47
Q

Too many RBCs leads to:

A

increased blood viscosity

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48
Q

Balance between RBC production and destruction depends on:

A
  1. hormonal controls

2. adequate supplies of iron, amino acids, and B vitamins

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49
Q

Erythropoiesis is controlled by the hormone:

A

erythropoietin (EPO)

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50
Q

Erythropoietin has a low number in blood to maintain:

A

basal rate

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51
Q

Depressed production of erythropoietin is caused by:

A

high RBC or O2 levels

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52
Q

EPO is released by ____in response to ____.

A

kidneys; hypoxia

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53
Q

Dialysis patients have how much RBC?

A

low RBC counts

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54
Q

Causes of hypoxia:

A
  1. decreased RBC numbers due to hemorrhage or increased destruction
  2. insufficient hemoglobin per RBC (iron deficiency)
  3. reduced availability of O2 (high altitudes)
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55
Q

What are the effects of EPO?

A
  1. Rapid maturation of committed marrow cells

2. Increased circulating reticulocyte count in 1-2 days

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56
Q

Athletic abuse of artificial EPO leads to:

A

higher RBC counts and thicker blood

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57
Q

Dietary requirements for erythropoiesis:

A
  1. nutrients
  2. iron
  3. vitamin B12 and folic acid
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58
Q

Nutrients required for erythropoiesis:

A
  1. amino acids
  2. lipids
  3. carbohydrates
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59
Q

Where is iron found?

A

65% in hemoglobin; the rest is found in the liver, spleen, and bone marrow

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60
Q

Free iron ions:

A
  1. are toxic
  2. iron ions are stored in cells as ferritin and hemosiderin
  3. iron transported in blood is bound to protein transferrin
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61
Q

vitamin B12 and folic acid is necessary for:

A

DNA synthesis for rapidly dividing cells (developing RBCs)

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62
Q

Life span of an erythrocyte:

A

100-120 days

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63
Q

Dying erythrocytes circulate to:

A

the spleen; macrophages engulf dying RBCs in the spleen

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64
Q

When erythrocytes die, heme and globin are separated, and what results?

A
  1. Iron is salvaged for reuse
  2. Heme is degraded to yellow pigment bilirubin
  3. the liver secretes bilirubin in bile into the intestines
  4. globin is metabolised into amino acids
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65
Q

When the liver secretes bilirubin into the intestines:

A
  1. bilirubin is degraded to the pigment urobilinogen

2. urobilinogen leaves the body in feces as stercobilin

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66
Q

After globin is metabolised into amino acids:

A

the amino acids are released into circulation

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67
Q

Characteristics of anemia:

A
  1. blood has abnormally low O2-carrying capacity
  2. blood O2 levels can not support normal metabolism
  3. accompanied by fatigue, pallor, shortness of breath, and chills
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68
Q

The three causes of anemia:

A
  1. blood loss
  2. low RBC production
  3. high RBC destruction
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69
Q

Causes of anemia, blood loss:

A
  1. acute hemorrhagic anemia

2. chronic hemorrhagic anemia

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70
Q

Causes of anemia, low RBC production:

A
  1. iron-deficiency anemia
  2. pernicious anemia
  3. renal anemia
  4. aplastic anemia
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71
Q

Causes of anemia, high RBC destruction:

A
  1. hemolytic anemia
  2. thalassemias
  3. sickle cell anemia
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72
Q

Aspects of acute hemorrhagic anemia

A
  1. rapid blood loss (e.g., stab wound)

2. treated by blood replacement

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73
Q

aspect of chronic hemorrhagic anemia

A

slight but persistent blood loss due to hemorrhoids or bleeding ulcer

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74
Q

Iron deficiency anemia is caused by:

A
  1. hemorrhagic anemia
  2. low iron intake
  3. impaired absorption
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75
Q

RBCs in iron-deficiency anemia are

A

monocytic, hypochromic

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76
Q

Iron-deficiency anemia is treated by

A

iron supplements

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77
Q

Pernicious anemia is what kind of disease?

A

autoimmune; destroys stomach mucosa

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78
Q

Pernicious anemia is caused by lack of:

A

intrinsic factor needed to absorb B12, which leads to deficiency of vitamin B12

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79
Q

In pernicious anemia, RBCs:

A

can not divide; leads to macrocytes

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80
Q

Pernicious anemia is treated by:

A

B12 injections or nasal gel

81
Q

Pernicious anemia can also be caused by:

A

low dietary B12 (such as in vegetarians)

82
Q

Renal anemia is caused by a lack of:

A

EPO

83
Q

Renal anemia often accompanies:

A

renal disease

84
Q

Renal anemia is treated with:

A

synthetic EPO

85
Q

In aplastic anemia:

A
  1. Red marrow is destroyed or inhibited by drugs, chemicals, radiation, or viruses
  2. all cell lines are affected; leads to clotting or immunity defects
86
Q

Aplastic anemia is treated:

A
  1. short-term: transfusions

2. long-term: transplanted stem cells

87
Q

Characteristics of hemolytic anemia:

A
  1. premature RBC lysis
  2. genetic basis for abnormal hemoglobin
  3. globin is abnormal
88
Q

Hemolytic anemia is caused by:

A
  1. hemoglobin abnormalities
  2. incompatible transfusions
  3. infections
89
Q

Aspects of thalassemias:

A
  1. typically occur in Mediterranean ancestry
  2. one globin chain is absent or faulty
  3. RBCs are thin, delicate, and deficient in hemoglobin
90
Q

Sickle-cell anemia arises from:

A

Hemoglobin S

91
Q

In hemoglobin S:

A

one amino acid is wrong in a globin beta chain

92
Q

Aspects of sickle-cell anemia:

A
  1. RBCs become crescent-shaped when they unload O2 or when blood O2 is low
  2. RBCs rupture easily and block small vessels; leads to poor O2 delivery which results in pain
93
Q

Two copies of the sickle-cell gene lead to:

A

sickle cell anemia

94
Q

one copy of the sickle-cell gene leads to:

A

sickle cell trait; disease is milder, leading to better chance to survive malaria

95
Q

Acute crisis of sickle cell anemia is treated with:

A

transfusions; inhaled nitric oxide

96
Q

To prevent sickling of RBCs, ____ induces fetal hemoglobin (which does not sickle) formation.

A

hydroxyurea

97
Q

Other ways of preventing sickling of RBCs:

A
  1. Blocking RBC ion channels
  2. Stem cell transplants
  3. Gene therapy
98
Q

Different polycythemias:

A
  1. polycythemia vera

2. secondary polycythemia

99
Q

What are the characteristics of polycythemia vera?

A
  1. bone marrow cancer leads to excess RBCs

2. severely increased blood viscosity

100
Q

What are the characteristics of secondary polycythemia?

A
  1. Less O2 available (high altitude) or EPO production increases which leads to higher RBC count
  2. blood doping
101
Q

Characteristics of leukocytes:

A
  1. function in defense against disease
  2. can leave capillaries via diapedesis
  3. move through tissue spaces by ameboid motion and positive chemotaxis
102
Q

A condition in which WBC count is over 11,000/mm^3

A

leukocytosis

103
Q

Two categories of leukocytes:

A
  1. granulocytes

2. agranulocytes

104
Q

What is the characteristic of granulocytes and what are granulocytes divided into?

A
  1. Granulocytes have visible cytoplasmic granules

2. Divided into: neutrophils, eosinophils, and basophils

105
Q

Characteristic of agranulocytes:

A

no visible cytoplasmic granules

106
Q

Agranulocytes are divided into:

A
  1. monocytes

2. lymphocytes

107
Q

Life span and size of granulocytes:

A
  1. shorter-lived than RBCs

2. larger than RBCs

108
Q

Shape of granulocyte nuclei:

A

lobed

109
Q

Cytoplasmic granules of granulocytes stain specifically with:

A

Wright’s stain

110
Q

Granulocytes are:

A

all phagocytic to some degree

111
Q

Neutrophils are also called _________.

A

polymorphonuclear leukocytes (PMNs or polys)

112
Q

Granules of neutrophils stain ____.

A

lilac

113
Q

Granules of neutrophils contain:

A

hydrolytic enzymes or defensins

114
Q

Size of neutrophils:

A

twice the size of RBCs

115
Q

Granules of eosinophils stain:

A

red

116
Q

Eosinophil nuclei are ___.

A

bilobed

117
Q

Characteristics of eosinophil granules:

A
  1. lysosome-like
  2. role in allergies and asthma
  3. role in modulating immune response
118
Q

Eosinophil granules release:

A

enzymes to digest parasitic worms

119
Q

Basophil granules contain ____.

A

histamine

120
Q

inflammatory chemical that acts as a vasodilator to attract WBCs to inflamed sites

A

histamine

121
Q

Basophils are funtionally similar to ____.

A

mast cells

122
Q

Characteristics of agranulocytes:

A
  1. Lack visible cytoplasmic granules

2. Have spherical or kidney-shaped nuclei

123
Q

Lymphocytes are found in:

A

mostly lymphoid tissue (e.g. lymph nodes, spleen); few circulate in blood

124
Q

Lymphocytes are crucial to:

A

immunity

125
Q

The two types of lymphocytes are:

A
  1. T lymphocytes (T cells)

2. B lymphocytes (B cells)

126
Q

What do T lymphocytes do?

A

They act against virus-infected cells and tumour cells.

127
Q

What do B lymphocytes do?

A

They produce plasma cells, which produce antibodies.

128
Q

Monocyte nuclei stain ____.

A

dark purple

129
Q

The life cycle of a monocyte:

A
  1. leave circulation
  2. enter tissues
  3. differentiate into macrophages
130
Q

What are the characteristics of monocytes?

A
  1. actively phagocytic cells

2. activate lymphocytes to mount an immune response

131
Q

Monocytes are crucial against:

A
  1. viruses
  2. intracellular bacterial parasites
  3. chronic infections
132
Q

Leukopoiesis is known as:

A

the production of WBCs

133
Q

Leukopoiesis is stimulated by 2 types of chemical messengers from ____ and _____.

A

red bone marrow; mature WBCs

134
Q

The 2 chemical messengers that stimulate leukopoiesis:

A
  1. interleukins

2. colony-stimulating factors (CSFs)

135
Q

CSFs are named for:

A

the WBC type they stimulate

136
Q

All leukocytes originate from _____.

A

hemocytoblasts

137
Q

Leukopoiesis starts out with two types of stem cells:

A
  1. lymphoid stem cells

2. myeloid stem cells

138
Q

In leukopoiesis, lymphoid stem cells give rise to:

A

lymphocytes

139
Q

In leukopoiesis, myeloid stem cells give rise to:

A

all others

140
Q

Progression of all granulocytes:

A
  1. myeloblast
  2. > promyelocyte
  3. > myelocyte
  4. > band
  5. > mature cell
141
Q

Granulocytes are stored in _____.

A

bone marrow

142
Q

Amount of WBCs produced relative to RBCs:

A

3 times more

143
Q

WBCs life span:

A

shorter; die fighting microbes

144
Q

Characteristics of monocytes (leukopoiesis):

A
  1. live several months

2. share common precursor with neutrophils

145
Q

Progression of monocytes during leukopoiesis:

A
  1. Monoblast
  2. > promonocyte
  3. > monocyte
146
Q

Life span of lymphocytes:

A

live few hours to decades

147
Q

Progression of lymphocyte during leukopoiesis:

A
  1. Lymphoid stem cell

2. > T lymphocyte precursors (travel to thymus); B lymphocyte precursors

148
Q

What are the different leukocyte disorders?

A
  1. leukopenia

2. leukemias

149
Q

Characteristic of leukopenia:

A

abnormally low WBC count–drug induced

150
Q

Leukemias are named according to:

A

abnormal WBC clone involved

151
Q

Myeloid leukemia involves:

A

myeloblast descendants

152
Q

Acute leukemia derives from ____.

A

stem cells

153
Q

Acute leukemia primarily affects ____.

A

children

154
Q

Chronic leukemia is more prevalent in ____.

A

elderly

155
Q

During leukemia, cancerous leukocytes fill ____.

A

red bone marrow

156
Q

During leukemia, overproduction of immature WBCs leads to:

A

crowding out of erythrocytes, which can cause anemia, and bleeding

157
Q

Over production of WBCs in leukemia produces:

A

overabundant nonfunctional, immature WBCs

158
Q

Results from leukemia:

A
  1. death from internal hemorrhage

2. overwhelming infections

159
Q

Leukemia can be treated by:

A
  1. irradiation
  2. antileukemic drugs
  3. stem cell transplants
160
Q

Characteristics of infectious mononucleosis:

A
  1. highly contagious viral disease–Epstein-Barr virus (human herpesvirus 4)
  2. high number of atypical agranulocytes
  3. runs its course with sleep
161
Q

Symptoms of infectious mononucleosis:

A
  1. tired
  2. aches
  3. chronic sore throat
  4. low fever
162
Q

Platelets are fragments of _____.

A

megakaryocytes

163
Q

Platelets stain:

A
  1. blue in outer region

2. purple in granules

164
Q

Granules of platelets contain:

A
  1. serotonin
  2. Ca2+
  3. enzymes
  4. ADP
  5. platelet-derived growth factor (PDGF)
165
Q

All of the things that granules of platelets contain, play a part in:

A

the clotting process

166
Q

What are the overall characteristics of platelets?

A
  1. Form temporary platelet plug that helps seal breaks in blood vessels
  2. Circulating platelets are kept inactive and mobile by nitric oxide (NO) and prostacyclin from endothelial cells lining blood vessels
167
Q

Life span of platelets:

A

age quickly, degenerate in about 10 days

168
Q

Platelet formation is regulated by ____.

A

thrombopoietin

169
Q

Platelets derive from ____.

A

megakaryoblasts

170
Q

Progression of platelets:

A
  1. mitosis but no cytokinesis

2. > megakaryocyte

171
Q

large cell with multilobed nucleus

A

megakaryocyte

172
Q

Hemostasis requires:

A
  1. clotting factors

2. substances released by platelets and injured tissues

173
Q

What are the three steps of hemostasis?

A
  1. Vascular spasm
  2. Platelet plug formation
  3. Coagulation (blood clotting)
174
Q

Characteristics of vascular spasm in hemostasis:

A
  1. vasoconstriction of damaged blood vessel

2. most effective in smaller blood vessels

175
Q

Vascular spasm is triggered by:

A
  1. direct injury to vascular smooth muscle
  2. chemicals released by endothelial cells and platelets
  3. pain reflexes
176
Q

Platelet plug formation acts in a ____.

A

positive feedback cycle

177
Q

During platelet plug formation, damaged endothelium exposes ____.

A

collagen fibres

178
Q

Exposure of collagen fibres leads to:

A

platelets sticking via the plasma protein [von Willebrand factor]

179
Q

After the platelets attach to the collagen fibres, they:

A
  1. swell
  2. become spiked and sticky
  3. release chemical messengers
180
Q

Chemical messengers that platelets release during platelet plug formation are:

A
  1. ADP
  2. serotonin
  3. thromboxane A2
181
Q

When platelets release ADP, what does it do?

A

causes more platelets to stick and release their contents

182
Q

When platelets release serotonin and thromoxane A2, what do they do?

A

enhance vascular spasm and platelet aggregation

183
Q

During coagulation, platelet plug is reinforced with ____.

A

fibrin threads

184
Q

During coagulation, blood is transformed from ____ to ____.

A

liquid; gel

185
Q

During coagulation, there is a series of reactions using ____.

A

clotting factors (procoagulants)

186
Q

What is needed to synthesise 4 of the 13 clotting factors?

A

Vitamin K

187
Q

The three phases of coagulation are:

A
  1. prothrombin activator is formed in both intrinsic and extrinsic pathways
  2. prothrombin is converted to enzyme thrombin
  3. thrombin catalyses fibrinogen which leads to fibrin
188
Q

Prothrombin activator is initiated by:

A

either intrinsic or extrinsic pathway (usually both)

189
Q

What are the aspects of prothrombin activator initiation?

A
  1. triggered by tissue-damaging events
  2. involves a series of procoagulants
  3. each pathway cascades toward factor X
190
Q

Factor X complexes with ___, ____, and ____ to form _____.

A

Ca2+; PF3; factor V; prothrombin activator

191
Q

What are the aspects of prothrombin activator initiation by intrinsic pathway?

A
  1. triggered by negatively charged surfaces (activated platelets, collagen, and glass)
  2. uses factors present within blood (intrinsic)
192
Q

What are the aspects of prothrombin activator initiation by extrinsic pathway?

A
  1. triggered by exposure to tissue factor (TF) or factor III (an extrinsic factor)
  2. bypasses several steps of intrinsic pathway, so it is faster
193
Q

Coagulation phase 2: pathway to thrombin: Prothrombin activator catalyses transformation of ____ to ____.

A

prothrombin; active enzyme thrombin

194
Q

Coagulation phase 2: pathway to thrombin: Once prothrombin activator is formed:

A

clot forms in 10-15 seconds

195
Q

Coagulation phase 3: common pathway to the fibrin mesh: Active enzyme thrombin converts ___ to ___.

A

soluble fibrinogen; fibrin

196
Q

Coagulation phase 3: common pathway to the fibrin mesh: Fibrin strands form _____.

A

structural basis of clot

197
Q

Coagulation phase 3: common pathway to the fibrin mesh: Fibrin causes plasma to:

A

become a gel-like trap for formed elements

198
Q

Coagulation phase 3: common pathway to the fibrin mesh: Thrombin (with Ca2+) activates ____.

A

factor XIII

199
Q

After activation of factor XIII, what does it do?

A
  1. cross-links fibrin

2. strengthens and stabilises clot

A&P II (8 decks)

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