Chapter 5: Blood Flashcards

(187 cards)

1
Q

What is blood?

A

It is a special type of C.T. That circulates inside blood.

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2
Q

What is blood formed of?

A

Cells and an extracellular fluid matrix called plasma.

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3
Q

What is the composition of blood?

A

It is made of 45% blood cells (erythrocytes, leukocytes, and platelets) and 55% plasma.

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4
Q

Examination of the blood using a blood film.

A

A drop of blood is spread on a glass slide and left to dry in air.

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5
Q

Blood examination using staining

A

With a neutral stain (Eg. Leishmans stain) formed of a mixture of red acidic stain Eosin and blue basic stain methylene blue dissolved in methyl alcohol (fixative).

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6
Q

Erythros

A

Red

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7
Q

What are Red blood corpuscles?

A

Non-nucleated biconcave discs.

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8
Q

RBC’s shape

A

Top view: rounded.
Side view: biconcave, to increase surface area for the exchange of gases.

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9
Q

What is the reason behind abnormal shapes of the RBC’s?

A

It is due to changes either in the cell membrane or Hb content. They are more fragile and more prone to hemolysis causing anemia.

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10
Q

What are the types of abnormal shapes?

A
  1. Spherocytes: spherical.
  2. Ovalocytes: oval.
  3. Sickle cell: crescent.
  4. Poikilocytes: pear.
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11
Q

RBC’s size

A

Diameter: 6-9 micrometers in with an average of 7.5 (the median).
Thickness: 2.2 micrometers (edge) and 0.8 (center).

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12
Q

Abnormal sizes of RBC’s

A

Microcytes: less than 6 micrometers.
Macrocytes: more than 9 micrometers.
Anisocytosis: different sizes.

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13
Q

RBC’s LM

A

Unstained blood film: appear colored due to Hemoglobin.
Stained blood film: stained with leishmans stain, RBC’s are rounded, non nucleated and acidophilic (hemoglobin is a basic protein), with a pale center (1/3 of the diameter of RBC’s are Normochromic).

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14
Q

RBC rouleaux appearance

A
  1. RBC’s may adhere to each other resembling piles of coins.
  2. This process occurs in slow circulation (abnormal).
  3. Due to the surface tension caused by their biconcave surface.
  4. Reversible, no damage to cells.
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15
Q

Erythrocyte sedimentation rate (ESR)

A

The long chains of RBC’s sediment more easily. This is the mechanism for ESR, which increases non specifically due to inflammation.

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16
Q

RBC’s EM

A
  1. No nucleus
  2. No organelles
  3. Filled with hemoglobin: appears electron dense and homogeneous.
  4. Cell membrane is flexible
  5. Cytoskeleton (actin and spectrin): keeps stability of shape and membrane.
  6. Glycocalyx includes antigenic sites for blood groups (ABO) and RH factor.
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17
Q

Life span of RBC’s

A

120 days

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18
Q

Fate of RBC’s

A

Old RBC’s are phagocytosed by macrophages in the liver, bone marrow, and spleen. It is secreted as bile pigments while iron is reused to form new RBC’s.

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19
Q

Osmotic fragility of RBC’s

A

RBC’s maintain normal shape in plasma (isontonic solution: OP of 0.9% saline.
Crenation: if placed in hypertonic solution, they shrink and show notches.
Hemolysis: if placed in hypotonic solution, they swell, burst, and leak hemoglobin.
Remaining cell membrane is called Cell ghost.

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20
Q

How are RBC’s counted?

A
  1. Hemocytometer.
  2. Electronic counting instruments.
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21
Q

What is the number of RBC’s?

A
  1. Average number of RBC’s: 5 million/mm3
  2. Adult male: 5-5.5 million/mm3
    Stimulators effect of male hormones on the bone marrow.
  3. Adult female: 4.5-5 million/mm3
  4. Newborns: highest in newborns and decreases gradually.
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22
Q

Abnormalities in number

A
  1. Anemia
  2. Polycythemia
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23
Q

Anemia

A

Decreased number of RBC’s below 4 million/mm3 (oligocythemia) and/or decreased hemoglobin concentration.

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24
Q

What are types of anemia?

A
  1. Pernicious anemia.
  2. Sickle cell anemia.
  3. Aplastic anemia.
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25
Pernicious anemia
Vitamin B12 deficiency anemia due to failed production of intrinsic factor by the stomach.
26
Sickle cell anemia
Abnormal rigid type of hemoglobin that accumulates at one side of the cell giving a crescent shape (Sickle RBC’s).
27
Aplastic anemia
Destruction of bone marrow Eg. By chemotherapy of irradiation. This leads to pancytopenia which is the decreased count of all blood cells).
28
Polycythemia
Increased number of RBC’s above 6 million/mm3. Due to hypoxia that stimulates the bone marrow to produce more RBC’s. It can be: 1. Physiological: high altitudes, muscular exercise, and in newborns. 2. Pathological: chronic lung and heart diseases.
29
Factors of adaptations of RBC’s
1. Plasmalemma. 2. Shape. 3. Content: 33% Hemoglobin, 66% H2O, 1% enzymes.
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Plasmalemma
1. Flexible: to be squeezed inside narrow capillaries. 2. Lipoproteins: highly selective for gas exchange.
31
Shape mode of adaptation
1. Biconcave: increasing surface area for gas exchange. 2. Rounded edges: easy passage in branched blood vessels.
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Content mode of adaptation
1. No nuclei or organelles: do not divide and give more space for hemoglobin. 2. Enzymes (Hemoglobin reductase): combine O2 and carbonic anhydrase which will carry CO2.
33
Platelets (thrombocytes)
Small oval cytoplasmic fragments.
34
What is the origin of platelets?
Develop from megakaryocytes.
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Platelets number
200,000- 400,000/mm3.
36
Platelets diameter
2-4 micrometers
37
Platelets LM
Oval, non nucleated fragments which have 2 zones: 1. Outer pale basophilic (clear) peripheral zone= hyalomere. 2. Central dark granular zone: granulomere.
38
Platelets EM
Cell membrane has a thick cell coat that helps platelets aggregation (platelet plug) to stop bleeding.
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Hyalomere
1. Cytoskeleton 2. Membranous channels
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Cytoskeleton hyalomere
1. Microtubules: maintain cell shape. 2. Actin microfilaments: help activated platelets to change shape and aid clot retraction.
41
Membranous channels hyalomere
1. Open canalicular system: invaginations of cell membrane to release serotonin ( vasoconstriction of injured vessel). 2. Dense tubular system: storage for Ca++.
42
Granulomere
Few mitochondria, ribosomes, glycogen (energy) and 3 types of granules: 1. a (specific) granules. 2. Delta (dense) granules. 3. Lambda granules.
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a (specific) granules
1. Clotting factors. 2. Growth factors. 3. Ca++.
44
Delta (dense) granules
1. Serotonin. 2. ATP. 3. ADP.
45
Lambda granules
Lysosomes for clot removal after healing of vessels.
46
Purpura or Thrombocytopenia
Decreased number of platelets less than XX.
47
What are the causes of thrombocytopenia?
1. Decreased production (bone marrow depression). 2. Increased breakdown (autoimmune disease).
48
Thrombocytopenia is characterized by?
1. Prolonged bleeding time. 2. Excessive bleeding after minor trauma.
49
Erythrocytes types
One type
50
Leukocytes types
5 types.
51
Erythrocytes content
Not true cells nor organelles.
52
Leukocytes content
True cells with nuclei and organelles.
53
Erythrocytes number
1. 4.5-5.5 million/mm3 in males. 2. 4-5 million/mm3 in females.
54
Leukocytes number
4000-11000/mm3
55
Erythrocytes size
6-9 micrometers with an average of 7.5.
56
Leukocytes size
6-20 micrometers.
57
Erythrocytes life span
120 days.
58
Leukocytes life span
Days to years.
59
Erythrocytes osmotic fragility
Easily hemolysed.
60
Leukocytes osmotic fragility
Not easily hemolysed.
61
Erythrocytes origin and maturation
Bone marrow.
62
Leukocytes origin and maturation
Bone marrow and lymphoid tissue.
63
Erythrocytes shape
Biconcave discs.
64
Leukocytes shape
Spherical.
65
Erythrocytes functions
Gas exchange.
66
Leukocytes function
Defense
67
Erythrocytes motility
Nonmotile
68
Leucocytes motility
Motile.
69
Life span of granular leucocytes
Shirt life span (few days) and are compensated by new cells from the blood stem cells in the bone marrow.
70
Nucleus of granular leucocytes
1. Single but segmented. 2. Condensed nucleus with peripheral heterochromatin and central euchromatin.
71
Cytoplasm of granular leucocytes
- Few organelles: 1. Golgi apparatus. 2. Mitochondria. 3. rER. - Contain both non specific (azurophilic) and specific granules. - Azurophilic= affinity for azure dye (oxidized methylene blue).
72
Granular leucocytes are classified according to?
Affinity of their specific granules to stain.
73
Neutrophils are also called
Polymorphonuclear leucocytes (PMNs).
74
Neutrophils percentage
60-70%.
75
Neutrophils diameter
10-12 micrometers
76
Neutrophils life span
Few days.
77
Neutrophils LM nucleus
Single but segmented 2-5 lobes connected by thin chromatin thread. Dark and has many shapes (PMN).
78
Neutrophils LM Barr body
Can be seen 3-6% of female cells.
79
Neutrophils LM cytoplasm
1. Specific granules: numerous fine, pale granules. 2. Azurophilic granules: few, large, large, stain purple with azure dye.
80
Neutrophils EM nucleus
1. Peripheral heterochromatin. 2. Small central euchromatin.
81
Neutrophil EM cytoplasm
1. Pseudopodia. 2. Few organelles. 3. More glycogen (energy).
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What are the two types of granules in neutrophils?
1. Azurophil (primary). 2. Specific (secondary).
83
Neutrophils Azurophil granules
1. Large, few, dark. 2. Considered primary lysosomes. 3. Contains myeloperoxidase defenses against bacteria and viruses.
84
Neutrophils specific granules
1. Small, many, pale. 2. Contain: - Collagenase. - Phagocytin. - Lysozyme. - Lactoferrin.
85
Functions of neutrophils specific granules
1. Primary line of defense (non specific). 2. Bacterial toxins attract neutrophils, which leave blood by migrating between endothelial cells of the blood vessels to C.T. By a process called Diapedesis to become motile and have pseudopodia (microphages).
86
What do neutrophils do in the Connective tissue?
1. Phagocytose bacteria 2. Dead neutrophils form pus cells. 3. Pus increases body temperature to stimulate heat regulating center in brain. 4. Attract monocytes to site of infection. 5. Stimulate bone marrow to form more neutrophils. 6. Secrete trephone substances that help wound healing.
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1. Phagocytose bacteria: specific granules.
Specific granules release their contents into phagocytic vesicle and C.T.: 1. Lactoferrin: binds to iron (essential for bacterial growth) (bacteriostatic). 2. Phagocytin: kill bacteria (bactericidal). 3. Lysozome: destroys bacterial proteins. 4. Collagenase: destroys collagen so facilitates movement of neutrophils.
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2. Phagocytose bacteria: Azurophil granules.
Azurophil granules release their enzymes: 1. Myeloperoxidase: kill bacteria. 2. Other enzymes: cause bacteria’s lysis.
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Neutrophilia
1. Increased percentage of neutrophils: X>75%. 2. Due to pyogenic infection. 3. Examples: - Acute tonsillitis. - Acute appendicitis. - Abscess.
90
Neutropenia
1. Decreases percentage of neutrophils: X<60%. 2. It is due to: - Typhoid fever ( most common cause). - Tuberculosis (T.B.). - Viral infection as influenza.
91
Eosinophils percentage
1-4%
92
Basophils percentage
0-1%
93
Eosinophils diameter
10-14 micrometers
94
Basophils diameter
10-12 micrometers.
95
Eosinophils life span
Few days
96
Basophils life span
Few days
97
Eosinophils LM
Nucleus: Biloed (horse-shoe shaped) connected by thick chromatin thread. Cytoplasm: contain large acidophilic specific granules.
98
Basophils LM
Nucleus: irregular segmented and S shape. Cytoplasm: coarse basophilic granules which obscure the nucleus. Metachromatically stained by toluidine blue: purple by heparin.
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Eosinophils EM
Nucleus: has peripheral heterochromatin with central euchromatin. Cytoplasm: few organelles and two types of granules: 1. Azurophil: small= lysosomes. 2. Specific: oval with electron dense corse of basic proteins internum and less dense periphery externum, contains: - Histaminase - Sulphatase - Eosinophil-derived neurotoxins
100
Basophils EM
Nucleus: peripheral heterochromatin with central Euchromatin. Cytoplasm: few organelles and two types of granules: 1. Azurophil: small = lysosomes. 2. Specific: large rounded electron dense that contains: - Histamine - Heparin - Eosinphil chemotactic factor - Leukotriens Cell membrane shows receptors for IgE.
101
Eosinophils functions
1. Terminate Allergy: - Secrete histaminase and sulphatase to destroy histamine and heparin. - Phagocytose antigen-AB complexes. 2. Defend against parasites: - Cytotoxic effect of internum: forms pores in their body. - Neurotoxins: nervous dysfunction of parasites.
102
Basophils functions
1. Secrete heparin: prevents clotting and promotes allergy. 2. Secrete histamine: vasodilation that leads to sudden decrease in blood pressure and anaphylaxis. 3. Attract eosinophils to the site of allergy by eosinophil chemotactic factor. 4. Leukotriens: Brochospasm which leads to bronchial asthma. 5. Limited phagocytic power.
103
Eosinophilia
Increase in percentage: X>5% due to: 1. Allergic diseases: urticaria, eczema, and bronchial asthma. 2. Parasites: Bilharziasis.
104
Eosinopenia
Decrease in percentage: X<1% due to: 1. Cortisone treatments: inhibit their release from bone marrow.
105
Basophilia
Increase in percentage: X>1% due to: 1. Allergic diseases. 2. Parasitic diseases. 3. Viral infections like chicken pox. 4. Liver cirrhosis.
106
Comparison between basophils and mast cells: life span
Basophils: few days. Mast cells: longer (weeks to months).
107
Comparison between basophils and mast cells: size
Basophils: 10-12 micrometers. Mast cells: 20-30 micrometers.
108
Comparison between basophils and mast cells: nucleus
Basophils: segmented. Mast cells: round.
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Comparison between basophils and mast cells: phagocytosis.
Basophils: slight. Mast cells: none.
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Comparison between basophils and mast cells: granules
Metachromatically stained due to histamine and heparin.
111
Comparison between basophils and mast cells: surface receptor
Antibody Ig E
112
No granular leucocytes are divided into:
1. Lymphocytes. 2. Monocytes.
113
Monocytes percentage
3-8%
114
Monocytes diameter
12-20 micrometers.
115
Monocytes life span
3 days in blood and 3 months in C.T.
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Monocytes LM
Nucleus: large, eccentric, kidney, shaped, pale with 1 or 2 nucleoli. Cytoplasm: non granular, non clear pale basophilic. Has frosted glass appearance due to lysosomes (Azurophil granules).
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Monocytes EM
Nucleus: Euchnomatic with clear nucleolus. Cytoplasm: 1. Have pseudopodia. 2. Mitochondria. 3. rER 4. Well developed Golgi apparatus. 5. Many lysosomes. Primary and secondary.
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Monocytes functions
Highly phagocytic cells: 1. Remain in the blood for 3 days. 2. Then they enter C.T. And change into macrophages to phagocytose bacteria and debris. 3. Antigen presenting cells. 4. The precursor of all phagocytic cells: - Dust cells of lungs. - Kupffer cells of the liver. - Osteoclasts of the bone. - Microglia of CNS.
119
Monocytosis
Increased percentage of monocytes: X>8% due to chronic infections: 1. T.B. 2. Syphilis and glandular fever. 3. Monocytic anemia.
120
Monocytopenia
Decreased percentage of monocytes: X<3% due to: 1. Pancytopenia.
121
Lymphocytes percentage
20-30%
122
Lymphocytes’ position in defense
2nd line of defense and 2nd most common cell of WBC’s
123
Lymphocytes
Immune competent cells: have surface marks (receptors) for antigens.
124
The two types of lymphocytes are divided according to?
Activity
125
What are the two types of lymphocytes?
Small and large.
126
Small lymphocytes percentage
15-20% of WBC’s.
127
Large lymphocytes percentage
5-10%
128
Small lymphocytes diameter
6-8 micrometers
129
Large lymphocytes diameter
10-15 micrometers
130
Small lymphocytes LM
1. Nucleus: dark and filling the cell. 2. Cytoplasm: little, pale basophilic rim around the nucleus.
131
Large lymphocytes LM
1. Nucleus: large, indented, pale with clear nucleolus. 2. Cytoplasm: abundant, deeply basophilic.
132
Small lymphocytes EM
1. Nucleus: heterochromatic. 2. Cytoplasm: many free ribosomes, two centrioles, and small Azurophil granules.
133
Large lymphocytes EM
1. Nucleus: euchromatic with prominent nucleolus. 2. Cytoplasm: more mitochondria, rER, G.A., and lysosomes.
134
Motility and distribution of lymphocytes
1. Actively motile, continuously circulating between the blood and lymphatic organs where they settle. 2. Only cells tat can return to blood. 3. Found in blood, lymph, and lymphatic tissue.
135
Classification of lymphocytes according to surface receptors
They have similar LM and EM. 1. T-lymphocytes. 2. B-lymphocytes. 3. Natural killer cells (NK cells).
136
T-lymphocytes percentage
60-80%
137
B-lymphocytes percentage
20-30%
138
Natural killer cells percentage
5-10%
139
T-lymphocytes life span
Years
140
B-lymphocytes life span
Few days- few months.
141
Natural killer cells life span
Years
142
T-lymphocytes maturation site
Stems cells in the bone marrow migrate to thymus gland, differentiate and acquire receptors. (Thymi education).
143
B-lymphocytes maturation site
1. Bursa in fabricus birds. 2. Bone marrow in mammals where they acquire receptors.
144
Natural killer cells maturation site
Developed from precursors of T and B cells and do not mature in thymus.
145
T-lymphocytes surface markers
T-cell receptors TCR Eg. 1. CD4 2. CD8 ptn
146
B-lymphocytes surface marks
Receptors for: Ig-M and Ig-D
147
Natural killer cells surface markers
1. CD 16 and others. 2. Have neither T nor B cell receptors.
148
T-lymphocytes function
Cell-mediated immunity
149
B-lymphocytes functions
Humoral immunity
150
Natural killer cells functions
1. Innate early immunity (no T-helper cells stimulation). 2. Similar to cytotoxic T-cells. 3. Secretion of interferon (antiviral).
151
T-lymphocytes types
1. Cytotoxic CD8+ T-cells. 2. Helper CD4+ T-cells. 3. Regulatory (suppressor) T-cells. 4. Memory T-cells.
152
Cytotoxic CD8+ T-cells
Secrete perforins that produce pores in the membrane of virally-infected, transplanted, or neoplasticism cells killing the, directly (cell-mediated immunity).
153
Helper CD4+ T-cells
Activate B-cells during humoral immune response.
154
Regulator (suppressors) T-cells
1. Maintain unresponsiveness to self-antigens. 2. Suppress excessive immune responses.
155
Memory T-cells
Rapid immune response on re-exposure to the same antigen (secondary immune response).
156
B-lymphocytes functions
When exposed to specific antigen they become activated by T-helper cells to: 1. Plasmablasts then plasma cells to produce antibodies (Humoral immunity). 2. B memory cells responsible for the rapid second immune response.
157
HIV
Human immunodeficiency virus that causes AIDS, destroys T-helper cells which leads to decreased immunity and patient becomes susceptible to infections.
158
Lymphocytosis
Increased percentage of lymphocytes: X>30% due to: 1. Physiological in children. 2. Chronic infections: - T.B. - whooping coughing. 3. Leukemia
159
Lymphocytopenia
Decreased percentage of lymphocytes: X<20% as in pancytopenia.
160
Total leukocytic count
Total number of WBC of the blood: 4000-11000/mm3.
161
How are leukocytes counted?
1. Haemocytometer. 2. Electron counting instrument.
162
Abnormalities in total count of leukocytes
1. Leucocytosis. 2. Leukocytopenia.
163
Leukocytosis
Increase in total number of WBC’s: X>11000/mm3. 1. Physiological: (transient): during pregnancy, labor, cold bath, and exercise. 2. Pathological: due to either acute or chronic infections.
164
Leukocytopenia
Decreased total number of WBC’s: X<4000/mm3. 1. X-ray. 2. Irradiation. 3. Typhoid fever. 4. Influenza virus. 5. Excessive use of some antibiotics.
165
Leukemia
Cancer that starts in the bone marrow which leads to a very high leucocytic count. Peripheral blood shows abnormal forms of WBC’s with immature cells.
166
Differential leukocytic count
The percentage of each type of WBC’s to the total number of leucocytes. It is counted in a blood film stained with Leishman stain.
167
Haempoiesis
Formation of blood cells in bone marrow and lymphatic organs. Eg: thymus.
168
Bone marrow
Myeloid tissue.
169
Types of one marrow
Red bone marrow and yellow bone marrow.
170
Red bone marrow
1. Active. 2. Present in most bones of children. 3. In adults: flat, short, and irregular bones.
171
Yellow bone marrow
1. Inactive. 2. In shafts of long bones of adults. 3. A store for fat. 4. Can change into active if needed.
172
Structure of the red marrow is composed of?
1. Stroma. 2. Free cells.
173
Stroma
1. Fixed cells. 2. Blood sinusoids.
174
Fixed cells
1. Reticular cells and fibers form the network in the background. 2. Fibroblasts. 3. UMC. 4. Pericytes. 5. Osteogenic. 6. Fat cells (the largest cells in the bone marrow).
175
Blood sinusoids
Wide, irregular blood capillaries lined with endothelial cells with non-continuous basement membrane through their pores. Blood cells leave to the blood.
176
Free cells
1. Developing stages of the blood cells. 2. The ratio of immature WBC’s to immature RBC’s is 5:1. Because the life span of WBC’s is shorter. 3. Stem cells.
177
What is the function of bone marrow aspirate or biopsy?
It is needed to diagnose disorders like aplastic anemia or leukemia.
178
When is bone marrow transplantation needed?
The donation is needed in bone marrow diseases such as: 1. Leukemia: stem cells are taken from a donor are infused into the same or another.
179
Reticulocytes size
Small: 9 micrometers.
180
Reticulocytes are
Immature RBC’s but slightly larger.
181
Reticulocytes cytoplasm
Acidophilic (Hb) with remnants of ribosomes and polysomes that form the reticulum.
182
Reticulocytes in peripheral blood
Percentage X<=1%.
183
When does the percentage of reticulocytes increase?
In cases of haemorrhage or destruction of RBC’s.
184
Reticulocytes stain
Super vital stain: brilliant cresyl blue.
185
Megakaryocytes size
Very large (mega) cells: 50-70 micrometers.
186
Megakaryocytes nucleus and cytoplasm
Single, multiloed dark nucleus and basic cytoplasm.
187
Megakaryocytes functions
1. Invaginations of cell membrane forms demarcation channels dividing the cytoplasm into fragments that shed platelets. (Formation of platelets goody info). 2. It extends pseudopedia (platelet ribbons) from which platelets detach.