Module 1: Normal Blood Components, Production, and Erythrocytes Flashcards

(251 cards)

1
Q

Define hematopoieses

A

Production and development of blood cells

Constant restoring of various blood cells

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2
Q

What does the hematopoietic system consist of?

A

Bone marrow, liver, spleen, thymus, and lymph nodes

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3
Q

What cells does erythropoieses produce? Leukopoiesis? Thrombopoiesis?

A

Red blood cells, white blood cells, and plateltes

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4
Q

What are myeloid cells?

A

Blood cells produced in the bone marrow

All blood cells except for lymphocytes

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5
Q

What are non-myeloid cells?

A

Blood cells not produced in the bone marrow

Lymphocytes, produced in the lymph nodes

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6
Q

What is medullaary hematopoiesis?

A

Production of myeloid cells in the bone marrow

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7
Q

What is extra-medullary hematopoiesis?

A

Production of myeloid cells outside of the bone marrow

**Not normal is adults!

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8
Q

What are the 3 stages of hematopoiesis?

A

Mesoblastic, hepatic, and myeloid

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9
Q

What is the mesoblastic phase of hematopoiesis?

A

2nd - 12th gestational weeks

Yolk sac and embryo form primitive blood stem cells (erythroblasts)

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10
Q

What is the hepatic phase of hematopoiesis?

A

6th gestational week to 2 weeks old
Liver and spleen produce more mature erythrocytes, then granulocytes, the monocytes
Lymph nodes begin forming lymphocytes
Bone marrow forms at 8 weeks gestation

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11
Q

What is the myeloid phase of hematopoiesis?

A

20th week gestation to death
Lymph nodes produce lymphocytes, bone marrow produces myeloid cells
Liver and spleen have potential for hematopoiesis if needed

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12
Q

What is the hematopoietic inductive microenvironment?

A

The bone marrow where myeloid cells can be produced and differentiate

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13
Q

What is the difference between red and yellow bone marrow?

A

Red - active bone marrow that can undergo hematopoiesis (children)
Yellow - inactive bone marrow, mostly fat (adults)

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14
Q

How is the liver involved with hematopoiesis?

A

Produces myeloid cells during gestation
In adults, synthesizes and produces transport proteins, stores vitamins and minerals for DNA and RNA synthesis, and breaks down hemoglobin

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15
Q

How is the spleen involved in hematopoiesis?

A

Produces myeloid cells during gestation

In adults, removes old and damaged RBC’s, and stores platelets

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16
Q

How does a splenectomy affect hematopoiesis?

A

Can no longer remove defective RBC’s
Increased platelets, increased poikilocytosis, increased denatured hemoglobin in RBC’s (Heinz bodies), increased retained nuclear material in RBC’s (Howell-Jolly bodies)

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17
Q

How is the thymus involved in hematopoiesis?

A

Production and maturation of T-lymphocytes

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18
Q

How are the lymph nodes involved in hematopoiesis?

A

Form new lymphocytes

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19
Q

What are stem cells?

A

Primitive, formative, unspecialized blood cells with potential to become several types of specialized blood cells

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20
Q

What is the most primitive hematopoietic stem cell?

A

Reticulum Cell

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21
Q

What can the reticulum stem cell differentiate into?

A

CFU-S (Colony forming unit - stem)

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22
Q

What is a CFU-S cell?

A

Colony forming unit - stem
pluripotential blood stem cell
multipotent lymphohematopoietic stem cell

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23
Q

What might a CFU-S stem cell differentiate into?

A

CFU-GEMM or CFU-L

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24
Q

What is a CFU-L stem cell?

A

Colony forming unti - Lymphoid

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25
What may a CFU-L stem cell differentiate into?
Lymphocyte precursor cells B-cell precursor T-cell precursor NK cell precursor
26
What is a CFU-GEMM stem cell?
Colony forming unit - Granulocyte, erythroid, monocyte, megakaryocyte Myeloid stem cell
27
What might a CFU-GEMM stem cell differentiate into?
``` CFU-Eo (eosnophils) CFU-Baso (basophils) CFU-GM (granulocyte, monocyte) BFU-E (Burst forming unit - erythroid) BFU-Meg (Burst forming unit - megakaryocyte) ```
28
What is a CFU-GM stem cell?
Colony forming unit - granulocyte, monocyte
29
What might a CFU-GM stem cell differentiate into?
CFU-G | CFU-M
30
What is a blast cell?
Earliest stage of a blood cell that can be identified as the precursor to a certain cell line
31
What are growth factors?
Proteins that ind to cells resulting in their activation and cellular proliferation/maturation
32
What are the 3 most important growth factors in hematopoiesis? What is each secreted from?
Colony stimulating factor (CSF) and interleukins (IL) - macrophages, lymphocytes, and bone marrow stromal cells (fibroblasts, endothelial cells) Erythropoietin (EPO) - kidneys Thrombopoietin (TPO) - liver
33
What are cytokines?
Multi-functional, potent, low molecular weight glycoprotein chemical mediators, secreted locally and inhibit or induce cellular RNA or protein synthesis.
34
What are cytokines secreted by?
T-lymphocytes (lymphokines) and monocytes/macrophages (monokines)
35
What 3 growth factors do monocytes/macrophages produce?
Tissue necrosis factor Interleukin-1 Interleukin-6
36
What 2 monocyte/macrophage produced growth factors work together? How?
Tissue necrosis factor + Interleukin-1 Activate and stimulate T-cells and bone marrow stromal cells to produce cytokines
37
What does Interleukin-6 do?
Stimulates B-cells to differentiate and produce antibodies, induces acute phase response to protein production by liver cells Augments responses of immune cells to hematopoietic growth factors and cytokines
38
What growth factors do T-lymphocytes produce?
Stem cell factor Flt ligand Interleukin-3 Interleukin-5
39
What 3 T-lymphocyte produced growth factors work together? How?
Stem cell factor + Flt ligand +Interleukin-3 Induce CFU-S cell to differentiate into CFU-GEMM or CFU-L and undergo mitosis
40
What does Interleukin-5 do?
Induces eosinophil growth and function
41
What growth factors do bone marrow stromal cells produce?
Granulocyte/monocyte stimulating factor Granulocyte (neutrophil) stimulating factor Monocyte/macrophage stimulating factor
42
What does granulocyte/monocyte stimulating factor do?
Induces CFU-GEMM cells to differentiate into CFU-Eo, CFU-baso, CFU-GM, BFU-E, and BFU-meg cells and undergo mitosis Stimulates phagocytic and cytotoxic functions in neutrophils and macrophages
43
What does granulocyte (neutrophil) stimulating factor do?
Induces maturation and mitosis of CFU-G and myeloblast cells
44
What does monocyte/macrophage stimulating factor do?
Induces maturation and mitosis of CFU-M and monoblast cells
45
What growth factors do kidney cells (juxtaglomerular region) produce?
Erythropoietin
46
What does erythropoietin do?
Induces maturation and mitosis of BFU-E, CFU-E, pronormoblasts, and NRBC's May induce other myeloid cell production if increased for a long period of time
47
What growth factors do liver cells as well as macrophages and endothelial cells produce?
Thrombopoietin
48
What does thrombopoietin do?
Induces maturation and mitosis of CFU-meg and megakaryocyte cells
49
What is tissue necrosis factor produced by?
Monocytes and macrophages
50
What is Interleukin-1 produced by?
Monocytes and macrophages
51
What is Interleukin-6 produced by?
Monocytes and macrophages
52
What is stem cell factor produced by?
T-lymphocytes
53
What is flt ligand produced by?
T-lymphocytes
54
What is Interleukin-3 produced by?
T-lymphocytes
55
What is Interleukin-5 produced by?
T-lymphocytes
56
What is granulocyte/monocyte stimulating factor produced by?
Bone marrow stromal cells | ex: fibroblasts, endothelial cells
57
What is granulocyte (neutrophil) stimulating factor produced by?
Bone marrow stromal cells | ex: fibroblasts, endothelial cells
58
What is monocyte/macrophage stimulating factor produced by?
Bone marrow stromal cells | ex: fibroblasts, endothelial cells
59
What is erythropoietin produced by?
Kidney cells (juxtaglomerular region)
60
What is thrombopoietin produced by?
Liver cells, macrophages, and endothelial cells
61
Define effective erythropoiesis
85% or more of developing RBCs in marrow are produced and released into the blood
62
Define ineffective erythropoiesis
Less than 85% of the developing RBC's in marrow are produced normally and make it into the blood (more than 15% die)
63
How long do NRBCs survive in the bone marrow and blood?
5 days and 0 days
64
How long do reticulocytes survive in the bone marrow and blood?
3 days and 1 day
65
How long do erythrocytes survive in the bone marrow and blood?
1 day and 110-120 days
66
How long do magakaryocytes survive in the bone marrow and blood?
7 days and 0 days
67
How long do platelets survive in the bone marrow and blood?
0 days and 8-10 days
68
How long do immature neutrophils survive in the bone marrow and blood?
5 days and 0 days
69
How long do bands and segmented neutrophils survive in the bone marrow, blood, and tissues?
7 days, 8 hours, and up to 6 days
70
How is increased demand for blood cells handled in the body?
1. Bone marrow releases immature forms (left shift) 2. Cell undergo more divisions 3. Accelerating maturation time 4. Increasing hematopoiesis in inactive areas - increasing # of blast cells - activating stem cells -> blasts (yellow marrow to red)
71
What are the 4 morphological changes that occur during blood cell maturation?
1. Cell size decrease 2. Nuclear/cytoplasmic ratio decrease 3. Nuclear maturation (smaller, lose nucleoli, more clumping) 4. Cytoplasm maturation (smaller, less blue, more pink)
72
How does each morphological feature change with maturation? ``` Cell size Nuclear/cytoplasmic ratio Chromatin pattern Presence of nucleoli Cytoplasm color Cytoplasm granulation Cytoplasm vacuoles ```
``` Decreases Decreases More condensed Not in mature cells Dark blue, light blue, blue-gray/pink No granules to non-specific to specific Increase with age ```
73
What is it called when a cells nucleus and cytoplasm develop at different rates?
Nuclear cytoplasmic asynchrony OR dyspoiesis
74
Define nuclear cytoplasmic asynchrony / dyspoiesis
Nuclear differentiation lags behind cytoplasm, or vise versa
75
Name the 6 stages of erythrocyte development
1. Pronormoblast (Rubriblast) 2. Basophilic normoblast (Prorubricyte) 3. Polychromatic normoblast (Rubricyte) 4. Orthochromic normoblast (Metarubricyte) 5. Polychromatiophilic (Reticulocyte) 6. Erythrocyte
76
Describe the morphology of a pronormoblast
14-24μ round central red-ish unclumped nucleus 0-2 nucleoli small deep blue cytoplasm
77
Describe the morphology of a basophilic normoblast
12-17μ Round/oval central/eccentric slightly clumped nucleus with parachromatin but no nucleoli small deep blue/purple cytoplasm
78
Describe the morphology of a polychromatic normoblast
10-15μ Round/oval central/eccentric deep purple/black heavily clumped nucleus with parachromatin and no nucleoli Small 4:1-2:1 polychromatic cytoplasm
79
Describe the morphology of a orthochromic normoblast
8-12μ Round central pyknotic black/brown nucleus Moderate bluish-pink cytoplasm
80
Describe the morphology of a reticulocyte
7-10μ No nucleus Clear gray/blue cytoplasm, polychromatic to pink
81
Describe the morphology of an erythrocyte
7-8μ No nucleus Pink cytoplasm
82
Describe the plasma membrane of a red blood cell
Double bipolar lipid layer 50% protein 40% lipid 10% carbohydrate Contains structural and contractile proteins (actin and spectrin), ATPase enzymes, surface antigens (A, B, H, etc), and receptor protein molecules (TfR)
83
Describe the structure of an RBC plasma membrane in regards to the lipid present
Two layers of glyco and phospholipids, polar group on the outside (bipolar) Glycolipids are antigens on the outer surface Cholesterol strengthens it
84
Describe the structure of an RBC plasma membrane in regards to the protein
Structural proteins are integral (penetrate membrane, glycophorin A) or peripheral (outside, spectrin) If lipids attached, may be antigenic Spectrin and actin maintain biconcave disk Band 3 channels ions
85
Describe the structure of the RBC plasma membrane in regards to the carbohydrates
Thin mucopolysaccharide layer on surface | Oligosaccharides attached to lipids and proteins as antigens
86
Define selective permeability
Ability to selectively allow molecules to move in and out of the membrane according to cell requirement
87
What are the 3 functions of the RBC plasma membrane?
1. Diffusion - water and lipid-soluble molecules cross 2. Facilitated diffusion - molecules cross by attaching to transport molecules (ex: glucose mediated by insulin) 3. Active transport - movement against concentration or electrical gradients, requires ATP and transport enzymes
88
Describe the sodium potassium pump
1 molecule of ATP pumps 2 molecules of K into the cell and 3 molecules of Na out of the cell against concentration gradients
89
Describe the calcium pump
ATP pumps Ca out of the cell
90
What happens when calcium builds up inside an RBC?
Elasticity is lost and hemolysis will occur
91
Why do RBC membranes have a negative charge?
To repel other RBCs in the blood to prevent damage by collisions
92
What happens when Na builds up inside an RBC?
Water follows Na into the cell causing swelling and hemolysis
93
What is present in an erythrocyte?
About 250 million hemoglobin molecules, organelles, enzymes, electrolytes, carbohydrates, lipids, and proteins
94
When is hemoglobin produced?
During RBC maturation 65% in normoblasts 35% in reticulocytes
95
What is required for hemoglobin production?
Iron, and other nutrients
96
What is hemoglobin made of?
Globin (4 polypeptide chains) and 4 heme molecules (protoporphyrin ring containing iron)
97
What is heme synthesis?
Creating of heme in the mitochondria and cytoplasm of NRBCs
98
Describe the pathway of heme synthesis
glycine + succinyl CoA ---> delta ALA (by activation by Vitamin B6 and erythropoietin) delta ALA ---> porphobilinogen (by activation by ALA dehydrase) porphobilinogen ---> uroporphyrinogen III ---> coproporphyrinogen III ---> protoporphyrinogen IX ---> protoporphyrin IX protoporphyrin IX ---> heme (ferroprotoporphyrin IX) (with iron by iron chelatase)
99
What would happen to heme synthesis if there is an iron deficiency?
Less heme would be formed in the NRBCs and protoporphyrin would accumulate
100
What would happen if there was a deficiency in enzymes that are required for heme synthesis?
``` Less heme would be formed or would stop altogether at the point of deficiency Other products (porphyrins) may be formed and cause diseases ```
101
What stimulates globin synthesis?
The presence of free heme in the cytoplasm of the NRBC
102
Where does globin synthesis take place?
In the ribosomes of the NRBCs
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What are the 6 possible polypeptide chains in globin synthesis?
Alpha, beta, gamma, delta, epsilon, and zeta
104
How is the golbin polypeptide chain decided?
Produced at different rates by mRNA depending on the person's age
105
How does heme bond to globin?
By the iron atom to two histidine sites on the globin | One is permanent one is reversible (used by O2 or H2O)
106
What are the 3 types of embryonic hemoglobin?
Hb Gower 1 (E4 or Z2E4) Hb Portland (Z2G2) Hb Gower 2 (A2E2)
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What are the characteristic of embryonic hemoglobin?
Produced in first 12 weeks gestation | NO BETA CHAINS
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What is fetal hemoglobin?
HbF (A2G2)
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What are the characteristics of fetal hemoglobin?
Higher affinity for O2 (not good at letting O2 go) Resists denaturation in alkalines and acids (lab tests) >75% of hbg at birth is HbF Not evenly distributed in all RBCs
110
What are the 2 adult hemoglobins?
HbA2 (A2D2) | HbA (A2B2)
111
What are the characteristic of adult hemoglobin A2?
<3% of total hgb Evenly distributed Same O2 affinity as A
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What are the characteristics of adult hemoglobin A?
Major component | 96-98% of total hgb
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What polypeptide chain has the best oxygen carrying and delivering ability?
Alpha | Adult hgb always has 2 alpha chains
114
What is hemoglobin A1C?
"Glycosylated/glycated hemoglobin" | Hemoglobin A and a glucose molecule attached to the beta polypeptide
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How is hemoglobin A1C testing used?
Used to monitor diabetes over a period of time | Normal person has <5%
116
Define reduced hemoglobin
HbA in which iron atoms are in the ferrous (2+) state | Required state for binding oxygen
117
Define oxyhemoglobin
HbO2 | Reduced hemoglobin carrying O2 bound to some or all iron atoms
118
Define deoxyhemoglobin
Reduced hb not carrying O2
119
Define methemoglonin
MetHb/oxidized hemoglobin | Iron atoms are in the ferric (3+) state, cannot bind O2
120
How does methemoglobin occur?
Peroxidases, oxidizing agents, certain drugs, chemicals, and gases Oxidation overwhelms reduction systems, or reduction systems fail/are inhibited and can't stop normal oxidation
121
How does the body fight the creation of methemoglobin?
Strong reducing systems in the cells keep levels at less than 0.5% (>2% is abnormal)
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What does increased methemoglobin cause?
Hypoxia due to decreased O2 carrying capacity
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What might methemoglobinemia rarely be caused by?
Inherited production of abnormal HbM or from enzyme deficiency in reducing pathway
124
Define carboxyhemoglobin
HbCO | HbA combined with carbon monoxide instead of oxygen
125
How does carboxyhemoglobin occur? What happens to the patient?
Exposure to carbon monoxide Affinity for CO is greater than O2, small amounts result in significant HbCO formation Maraschino cherry red cyanosis develops in carbon monoxide poisoning
126
Define sulfhemoglobin
sulfHb/verdoglobin HbA + inorganic sulphides or H2O2 One S atom combines with Hb and a permanent covalent bond occurs
127
What causes sulfhemoglobin?
Sulphur containing medicine, H2S gas, sulphur containing foods
128
What do maturing nucleated red blood cells use their energy on?
Creating proteins for maturation and mitosis like hemoglobin, membrane proteins, and enzymes
129
What do mature red blood cells use their energy on?
1. Active transport (NaK pump, Ca pump), endergonic reactions (phosphorylation of glucose in glycolysis) 2. reducing co-enzymes (NAD reduced to NADH reduced to NADPH)
130
Where do red blood cells get their energy from?
2 pathways of glycolysis 1. Embden-Meyerhof Pathway (anaerobin) 2. Pentose Shunt Pathday (hexose-monophosphate shunt)
131
What is formed in the embden-meyerhof pathway?
2 molecules of ATP (ADP+2Pi+glucose energy)
132
How is ATP used in a red cell?
Active transport pumps (NaK, Ca) | Other endergonic reactions
133
What is formed in the pentose shunt pathway?
1 NADPH molecule (NADH reduction)
134
What is NADPH used for in a red cell?
``` Reduced GSGG (oxidized glutathione) to GSH (reduced glutathione), which (with glutathione peroxidase) prevents oxidative damage to the cell by neutralizing oxidizers Also metHb --> Hb with metHb reductase ```
135
What happens if either glycolysis pathway activity is decreased?
Reduced NADH, NADPH, and ATP production leading to early hemolysis (death) due to membrane or enzyme damage and active transport failure
136
What are the functions of RBCs?
1. Oxygen transport 2. Carbon dioxide transfer/hydrogen buffering 3. Nitric oxide transport
137
How do RBCs transport oxygen?
O2 binds to ferrous iron in hemoglobin (each heme binds 1 O2, so 4 O2 per hemoglobin) Oxygenation is reversible
138
Define oxygen saturation | What is the normal amount?
Amount of O2 carried by the hemoglobin in the blood, expressed as a percent of total capacity ex: 90% = 90% of available sites are carrying O2 Normal arteriol = 95% Normal venous = 75%
139
Define partial pressure of oxygen
"Oxygen tension" Amount of O2 in the plasma ex: pO2 = 40mmHg
140
What factors affect oxygen saturation?
1. O2 availability (reduced O2) 2. Reduced hemoglobin availability (abnormal Hb, reduced amount) 3. Hb oxygen affinity (bonding attractiveness of O2 to Hb)
141
What is high O2 affinity? Low O2 affinity?
High - Hb quickly and easily bind O2 and hang on (highest in lungs) Low - Hb releases O2 and has more difficulty binding (lowest in tissues)
142
How is O2 affinity determined?
1. Heme-heme interaction (molecular structure changes) 2. Temperature 3. Bohr Effect (pH) 4. 2, 3 Biphosphoglycerate (BPG)
143
Define heme-heme interaction
"Cooperative binding" | As O2 molecules bind to Hb, the structure changes to increase the affinity
144
How does temperature affect O2 affinity?
Increased temperature = decreased affinity (O2 released) | Decreased temperature = increased affinity (O2 bound)
145
How does the Bohr Effect (pH) affect O2 affinity?
7.40pH is normal pH decreases at tissues (7.36) decreasing affinity pH increases at the lungs (7.44) increasing affinity
146
What is 2, 3-BPG?
2, 3-biphosphoglycerate, a by-product of the embden-meyerhog pathway Produced by red cells during hypoxia at the tissues
147
How does 2, 3-BPG affect O2 affinity
2, 3-BPG (produced by the red cells) binds to Hb and changes its shape, decreasing affinity and releasing ALL O2 Called desaturation
148
What are the axises on the O2 affinity curve?
X axis - pO2 (plasma concentration) | Y axis - O2 saturation (O2 on Hb)
149
What factors would cause the O2 affinity curve to shift to the right? (less saturation)
Decreased pH, increased temperature, increased 2, 3-BPG
150
What factors would cause the O2 affinity curve to shift to the left? (more saturation)
Increased pH, decreased temperature, decreased 2, 3-BPG
151
What hemoglobin is associated with increased affinity? Decreased affinity?
Increased affinity = HbF | Decreased affinity = HbS (sickle cell)
152
How does carbon dioxide transport work?
85% diffuses into the RBCs and is converted to HCO3 (bicabonate) and H+ by carbonic anhydrase and H2O The H+ ions bind to negatively charged amino acids The HCO3 diffuses out of the RBC into the plasma until equilibrium is reached
153
What is the buffering action of hemoglobin?
When the H+ created with CO2 becomes HCO3 in the RBC, it attaches to negatively charged amino acids in the hemoglobin which prevents it from accumulating and decreasing the pH
154
What is the chloride shift?
When HCO3 diffuses out of the RBCs chloride ions usually follow it to balance the electrical charge
155
What happens to the 15% of CO2 that does not get converted to HCO3?
10% is carried as carbamino hemoglobin bound to globin amino acids 5% is carried in the plasma as gas
156
What is nitric oxide?
Vessel dilator, muscle relaxant produced by endothelial cells to maintain vascular patency (dilation) and resist platelet adhesion
157
How is nitric oxide transported?
It attaches to free iron atoms in the heme and is carried from the tissues to the lungs Thought to be released when oxygen tension is low, causing vasodilation and increased blood flow, and the opposite in high oxygen tension
158
What is super nitric oxide? How is it transported?
Nitric oxide with an extra electron | Attaches to cystine in the globin polypeptides and moves from the lungs to the tissue
159
How are old RBCs removed from circulation?
Extravascularly - macrophages in the liver sinusoids and spleen Intravasculrly - (small amount) hemolysed by hard collisions
160
What is extravascular hemolysis?
Occuring outside of the bloodstream, usually the liver and spleen
161
What happens when an RBC is phagocytised?
Useful parts are stored or released into circulation | Non-usable portions are excreted by the liver or kidneys
162
How does hemoglobin catabolism work?
Hb is digested by lysozymes in the macrophages by: 1. heme detached from globin 2. globin hydrolyzed to amino acids 3. iron detached from protoporphyrin and stored (bound to apoferritin as ferritin) or moved into plasma bound to transferrin 4. protoporphyrin oxidized to biliverdin, releasing CO, and moved into plasma and reduced to indirect bilirubin
163
What happens to unconjugated bilirubin in the blood?
Bound by albumin and brought to liver Albumin attaches to Kupffer cells (macrophages) Bilirubin is pinocytosed and conjugated
164
What happens to bilirubin after it is conjugated in the liver?
Moves into bile ducts then gallbladder | Released into the duodenum and is reduced by bacteria to urobilinogen and stercobilinogen
165
What happens to urobilinogen in the duodenum?
Some is reabsorbed and returned to the liver, then makes its way back Most is converted to urobilin, stercobilin, and mesobilin and excreted
166
What happens if extravascular hemolysis is increased?
Increased hemoglobin catabolism, increased waste | Hyperbilirubinemia, increased urine urobilinogen, increased CO
167
What may cause hyperbilirubinemia?
Increased extravascular hemolysis Liver disease/failure, cannot conjugate properly (increased indirect) Bile duct obstruction, cannot get rid of bilirubin (increased direct)
168
What is intravascular hemolysis?
Hemolysis of RBCs in the blood stream
169
What happens in intravascular hemolysis?
Hemoglobin is released into the plasma and is bound by haptoglobin The complex is pinocytosed by macrophages in the liver and spleen Catabolism occurs the same way as in extravascular hemolysis
170
What happens if there is increased intravascular hemolysis?
Hemoglobinemia, haptoglobin might be used up
171
What happens if there is not enough haptoglobin to bind hemoglobin in the plasma?
Hemoglobin dissociates into heme and globin, heme oxidizes to metheme and binds to albumin (methemalbumin) causing methemalbuminemia (brown plasma) or Hemoglobin dissociates into dimers, excreted by the glomerulus and excreted in urine (hemoglobinuria) Some is absorbed by the renal tubular cells and iron is stored as hemosiderin, killing the cells, and shedding into the urine (hemosiderinuria)
172
What are signs of increased intravascular hemolysis?
``` Hemoglobinemia Decreased haptoglobin Methemalbuminemia Hemoglobinuria Hemosiderinuria ```
173
Explain the difference between medullary hematopoiesis and extra-medullary hematopoiesis
Medullary - production of myeloid cells in bone marrow | Extramedullary - production of myeloid cells outside bone marrow, in liver and spleen
174
Which of the normal blood cells is a non-myleoid cell?
Lymphocytes
175
Which of the myeloid cells is found only in the marrow? Why?
Megakaryocytes because the cytoplasm disintegrates into platelets in the marrow
176
Blood cells are of epithelial origin a. true b. false
b. false Mesodermal and connective tissue origin
177
The heart develops before the bones a. true b. false
a. true
178
The liver assumes main responsibility for production of blood cells after the seventh month of gestation a. true b. false
b. false The liver does this after the sixth week of gestation
179
In infants and children up to 10 years of age, nearly all of the bone marrow is active (yellow) a. true b. false
b. false It is active, but it is red not yellow. Yellow marrow is fatty and inactive
180
What are the names and duration of each of the major phases of hematopoiesis in the embryo, fetus and adult?
Embryo - mesoblastic, 2-12 weeks gestation Fetus - hepatic, 6th week gestation - 2 weeks old Adult - myeloid, 20th week gestation to death
181
Name the cell described: Can become any connective tissue cell
Reticulum cell
182
Name the cell described: The blast cell of a neutrophil
Myeloblast
183
Name the cell described: Committed to become any myeloid cell
CFU-GEMM
184
Name the cell described: The largest hematopoietis cell
Megakaryocyte
185
In hemtopoiesis what is responsible for the mitosis of blast cells?
The bone marrow environment
186
In hematopoiesis what is responsible for the differentiation of blast cells?
Specific growth hormones
187
For a developing series of blood cells, describe the usual morphologic changes that occurin the marrow from blast to mature forms: In cell size In nuclear chromatin clumping In color of cytoplasm
They get smaller It gets more clumped or condensed Blue basophilia of the blast cell to colors that reflect the changing contents of the cytoplasm of mature cells
188
What is meant by nuclear cytoplasmic asynchrony?
The nucleus or the cytoplasm develops faster or slower than normal
189
What is ineffective erythropoiesis?
More than 15% of the red cells developing in the marrow die before release into the blood
190
Name stromal cells in the bone marrow
Fibroblasts, endothelial cells
191
Name 4 immediate progeny of the CFU-GEMM
BFU-E CFU-meg CFU-GMEo CFU-baso
192
Define a blast cell
Earliest for of a blood cell that is morphologically recognizable by physical appearance as belonging to a specific cell line
193
What kinds of cells secrete cytokines?
Lymphocytes, macrophages, bone marrow stromal cells
194
List the secretor cell(s) and function(s) of the following cytokine: IL-1
Macrophages | Activates and induces cytokine production by T cells and marrow stromal cells
195
List the secretor cell(s) and function(s) of the following cytokine: IL-3
T lymphocytes | Induces maturation and mitosis of CFU-S in synergy with SCF, Flt-L
196
List the secretor cell(s) and function(s) of the following cytokine: GM-CSF
Marrow stromal cells Induces maturation and mitosis of CFU-GEMM, CFU-GMEo, CFU-GM, and CFU-base Activates phagocytic and killing functions of neutrophils and macrophages
197
List the secretor cell(s) and function(s) of the following cytokine: IL-5
Marrow stromal cells | Induces eosinophil growth and function
198
List the secretor cell(s) and function(s) of the following cytokine: EPO
Kidney cells | Induces maturation and mitosis of the erythroid cell line
199
List the secretor cell(s) and function(s) of the following cytokine: TPO
Liver cells | Induces maturation and endomitosis of megakaryoblasts
200
What is the most important property of the erythrocyte plasma membrane?
Selective permeability
201
Briefly describe the sodium pump
ATP is used to move Na out of and K into the cell against concentration gradients to maintain necessary intracellular concentrations of ions
202
What part(s) of the erythrocyte plasma membrane may act as antigens?
Glycoproteins, glycolipids
203
What part(s) of the erythrocyte plasma membrane maintain the shape of the cell?
Actin and spectrin
204
What part(s) of the erythrocyte plasma membrane are lipids?
Phospholipids and cholesterol
205
What is a concentration gradient?
A difference in concentration of substances across a membrane
206
What is the specific site of synthesis of heme?
Mitochondria
207
What is the specific site of synthesis of globin?
Ribosomes
208
Why is hemoglobin not synthesized in mature erythrocytes?
They have no nucleus to make mRNA and they have no ribosomes to make the polypeptides from mRNA if they had any
209
In the first reaction in the synthesis of heme name the reactants
Glycine and succinyl-CoA
210
In the first reaction in the synthesis of heme name the reaction product
Delta-aminolevulinic acid
211
In the first reaction in the synthesis of heme name the reaction enzyme
Delta-aminolevulinic acid synthetase
212
In the first reaction in the synthesis of heme name the reaction coenzyme
Pyridoxine (Vitamin B12)
213
In the first reaction in the synthesis of heme name the enzyme activator
Erythropoietin
214
In the first reaction in the synthesis of heme name the reaction inhibitor
Heme
215
If any of the enzymes in the reactions leading to the formation of heme are deficient or absent, then _____ accumulates in the red cells and other tissues, causing a disease called _____
Porphyrins | Porphyria
216
What are the symbols and Greek names for the six types of polypeptide chains that form the various globins during the lifetime of a normal individual (from fetus to adult)
Alpha, beta, gamma, delta, epsilon, zeta
217
A normal hemoglobin molecule contains ____ heme molecules, globin(s), and ____ polypeptides making up each globin
Four | Four
218
Hb Gower is found in the embryo, fetus, and adult a. True b. False
b. false | Embryo only
219
Hb F is also called female hemoglobin a. True b. False
b. false | Fetal hemoglobin
220
HbA2 is the major component of adult Hb a. True b. False
b. false | Minor component
221
Alpha polypeptide chains are found in all types of normal adult hemoglobin a. True b. False
a. true
222
Alpha2Delta2 is the polypeptide formula for HbA2 a. True b. False
a. true
223
Reduced hemoglobin contains iron atoms in the ferrrous state a. True b. False
a. true
224
Write out the full name for NAD and NADPH
Nicotinamide adenine dinucleotide | Nicotinamide adenine dinucleotide phosphate
225
Methemoglobinemia represents a condition in the blood where more than ____% of total Hb is metHb
2%
226
Methemoglobin is oxidized Hb a. True b. False
a. true
227
Methemoglobin is irreversible a. True b. False
b. false
228
Methemoglobin carries oxygen a. True b. False
b. false
229
Methemoglobin contains low ferric iron
a. true
230
What are 2 types of reduced HbA and how are they different from one another?
Oxyhemoglobin - reduced Hb that can and is carrying oxygen | Deoxyhemoglobin - reduced hemoglobin that can, but is not carrying oxygen
231
Which type of Hb results from binding a sulphur into the molecule?
Sulfhemoglobin
232
Which type of Hb results from binding carbon monoxide into the molecule?
Carboxyhemoglobin
233
Which type of Hb results from binding carbon dioxide into the molecule?
Carbinohemoglobin
234
Which type of Hb results from binding oxygen into the molecule?
Oxyhemoglobin
235
Which energy pathways are lost after the RBC extrudes its nucleus and other unnecessary cellular organelles?
The Kreb's cycle and the electron transport system
236
Mature red cells use the Embden-Meyerhof pathway of reactions to produce _____ and _____
NADH and ATP
237
Mature red cells use the pentose shut to produce _____
NADPH
238
How does NADPH prevent oxidation of cellular proteins?
Reduces glutathione, which reduces oxidizing agents in the cell
239
What two cellular compounds (produced by glycolysis) are used to reduce metHb
NADH and NADPH
240
What is 2, 3-BPG, how is it produced, and what does it do?
2, 3-Biphosphoglycerate Produced in a small pathway off the Embden-Meyerhof pathway called the Rapport-Leubering Shunt Binds with Hb in red cells and forces dissociation of O2 (desaturation)
241
How does oxygenation differ from oxidation?
Oxygenation - binding and release of oxygen without gain or loss of electrons Oxidation - loss of electrons in a reaction
242
What is the oxygen affinity of hemoglobin? What 4 factors influence affinity in the red cell?
Oxygen affinity is the chemical bonding attractiveness of oxygen to Hb 1. pH 2. Temperature 3. 2,3-BPG 4. Number of oxygen atoms already bound (heme-heme interaction)
243
Briefly outline the effects of increasing and decreasing pH on the oxygen affinity of hemoglobin
pH increases, oxygen affinity also increases | pH decreases, oxygen affinity also decreases
244
What component of hemoglobin binds oxygen at the lungs and carries it to the tissues?
The iron atoms in the heme
245
What are the 3 ways in which CO2 formed in the tissues is carried to the lungs?
1. As HCO3 2. As carbaminohemoglobin 3. As a dissolved gas in the plasma
246
What enzyme is responsible for catalyzing the reactions that result in the transport of the great majority of CO2 by the red cells?
Carbonic anhydrase
247
What are the two types of hemolysis that destroy about 10 billion erythrocytes per hour in the average person and where does each type of hemolysis occur?
Extravascular - by the sinusoidal mononuclear phagocytes of the liver and spleen Intravascular - hemolysis in circulation
248
The only physiologic reaction that produces carbon monoxide occurs in the catabolism of hemoglobin by reticuloendothelial macrophages. What is the reaction?
The catabolism of protoporphyrin IX into biliverdin
249
Differentiate direct from indirect bilirubin
Direct - conjugated with one or two molecules of glucuronic acid Indirect - not conjugated with glucuronic acid
250
If there is a great deal of abnormal hemolysis, list some lab findings if the hemolysis occurs extravascularly
Increased plasma bilirubin Increased urobilinogen in urine Increased CO in expired air
251
If there is a great deal of abnormal hemolysis, list some lab findings if the hemolysis occurs intravascularly
``` Hemoglobinemia Decreased plasma haptoglobin Hemoglobinuria Methemalbuminemia Hemosinderinuria ```