Hematopoiesis & Erythropoiesis Flashcards
blood volume in females
4-5L
blood volume in males
5-6L
blood pH
7.35-7.45
Blood composition (55%)
Plasma/Serum (fluid)
Water, proteins, other solutes
Blood composition (45%)
Formed elements (cells)
RBCs, WBCs, Platelets
Blood Specific Gravity
1.049-1.065
Centrifuge Blood Sample (Top, middle, bottom)
Top layer - Plasma/Serum
Middle - “Buffy Coat” - WBCs + platelets
Bottom Layer - RBCs
Hematocrit
% of packed red cells
Anticoagulant used
Plasma
Clotting factors present
Example of clotting factor
Fibrinogen
No anticoagulant used
Serum
Some clotting factors consumed
Gold/Red Top in a blood separation sample
No anticoagulant
Green/Purple/Blue - Blood Separation
Anticoagulant present
Blood Collection - Capillary
Adult - fingerstick
Baby - Heel stick
Blood Collection - Venipuncture
Median Cubital
Median Cephalic
Blood Collection - Arterial
Radial Artery
Brachial Artery
Femoral Artery
WBC Count (Conventional Units)
4.8-10.8 x 10^3/ microL
RBC Count - Male
4.7-6.1 x 10^6 / microL
RBC Count - Female
4.2-5.4 x 10^6 / microL
Hematocrit (HTC) Male
42-52%
Hematocrit (HTC) - Female
37-47%
Major Blood Functions
Transport oxygen to cells
Transport CO2 and wastes away
Provides defense
Regulates body pH, body temperature, fluid balance
Major blood functions are required to maintain
Homeostasis
Homeostasis
maintaining a constant environment or equilibrium
Hematopoiesis
Formation of blood cells
Hematopoiesis Characteristics
Takes place in hematopoietic tissue
Maintains a cell population of erythrocytes, leukocytes, platelets.
Responsible for the maturation and division of hematopoietic stem cells
Platelets
G
Erythrocytes
A
Neutrophils
I,E,C
Eosinophil
D
Basophil
J
Lymphocytes
B,H
Monocytes
F
Platelets (Thrombocyte)
Size?
Nucleus?
Average Life Span?
Function?
Size: 1-4 micro m
Cytoplasmic fragment, no nucleus
Average lifespan: 10 days
Function: homeostasis
Platelets Homeostasis
Process in which blood clots and bleeding is arrested
Neutrophil Function
Inflammation & Phagocytosis
1st line of defense against infections
Most abundant
Platelets (Thrombocyte)
Neutrophils
Neutrophil Nucleus
2-5 lobes connected by a thin filament
Segmentation allows passing through openings between lining cells
Neutrophil cytoplasm
light pink with secondary granules (pink/neutral)
Average life span neutrophils
6-10 hrs
Eosinophil
Eosinophil function
defense in parasitic and fungal infections
Eosinophil nucleus
bi-lobed with condensed chromatin
Eosinophil cytoplasm
secondary granules (reddish/orange)
Basophil
Basophil function
mediates allergic reactions
Basophil Nucleus
often obscured by large secondary granules
least abundant WBC in circulation
Basophil cytoplasm
dark secondary granules
- histamine → vasoconstriction
- Heparin → blood thinner
granules are water soluble
What do granules in basophils contain?
Histamine and Heparin (play a role in homeostasis)
histamine
vasoconstriction
heparin
blood thinner (anticoagulant)
Lymphocyte function
immune response and viral infection
lymphocytes
Lymphocyte nucleus
clumped chromatin
lymphocyte cytoplasm
stains blue, periphery more intense
Lymphocyte granules
- usually none
- can have a few (countable) azurophilic granules - reddish pink
Monocyte
Monocyte function
phagocytosis
Monocyte nucleus
- Horseshoe-shaped/lima bean/convoluted
- Lacy, fine chromatin
Shape/outline of monocyte is irregular
Monocyte cytoplasm
- Dull gray-blue
- Cloudy
- Many small, red-purple staining granules
- Vacuoles often present
A - Lymphocyte
B - Monocyte
A - Lymphocyte
B - Monocyte
Surrounding cells Lymph vs. Mono
Lymph - indented by RBCs
Mono - project pseudopods between or compressing nearby RBCs
Mature RBC - Erythrocyte
Major function of mature RBC
Oxygen transport from lungs to tissues
Shape of RBC
6-8 micro m Biconcave Disc (shallow middle)
Allows for max surface area for gaseous exchange
Hemoglobin is 95% dry weight
Mature RBC lifespan
120 day lifespan
Can travel 200-300 miles during this time
Organs within hematopoietic system
Bone Marrow
Liver
Spleen
Lymph Nodes
Thymus
Embryo Developmental Stage
Mesoblastic phase
Fetal Developmental Stage
Hepatic Phase
Birth Developmental Stage
Medullary Phase
Embryo - Mesoblastic phase
- 2 weeks - 2 months gestation
- Yolk sac - mesoderm layer
- Forms primitive erythroid cells
- Hemoglobin formed
- Hgb Gower-1
- Hgb Gower-2
- Hgb Portland
All referred to as embryonic hemoglobin
Fetus - Hepatic Phase
- 2 months - 7 months gestation
- Liver and Spleen
- Additionally forms WBCs and Megakaryocytes (platelets precursor)
- Hgb formed
- Fetal hemoglobin
- Hemoglobin A1 (small amounts)
Birth - Medullary Phase
(bone marrow)
- 7 months - rest of life!
- Bone marrow = intramedullary hematopoiesis
- Red marrow
- Diapedesis
- Hgb formed post birth
- Hemoglobin A1
- Hemoglobin A2 ( small amounts)
Infancy and Early Childhood
Volume of red marrow in infant and adult are approximately equal.
As one is aging, the distal long bones and axial skeleton is expanding
At 4 years, yellow marrow (fat) starts replacing red marrow → limits hemopoietic sites
Adolescence and Adulthood
Only active hemopoietic/red marrow in axial skeleton
- Sternum
- Ribs
- Pelvis
- Vertebrae
- Skull
Other bones contain primarily yellow marrow
At the age of 40+
Only find hematopoietic/red marrow in:
- Sternum
- Ribs
- Pelvis
- Vertebrae
- 50% red, 50% yellow marrow
Preferred bone marrow aspiration sites
Pelvis and Sternum
Last to be replaced by yellow marrow