blood, bone marrow, & hemopoiesis Flashcards
functions of blood and bone marrow
- transport (O2, CO2, hormones, etc)
- thermoregulation
- maintain pH and osmotic balance*
- pathway for WBC migration in body
- source of interstitial fluid (ECM and edema)
- development
what is hematopoiesis?
the process of producing blood and bone marrow
blood and lymphatic cells come from…
lateral mesoderm
composition of whole blood (in order of sedimentation and % comp)
- plasma (55%)
- buffy coat (<1%)
- erythrocytes (44%)
* in order of sedimentation!!**
plasma composition
- 92% water
- 7% plasma proteins (58% albumin, 37% globulins, 4% fibrinogens)
- respiratory gases (O2, CO2)
- electrolytes
buffy coat composition
- platelets
- leukocytes (neutrophils, lymphocytes, monocytes, eosinophils, basophils)
formed elements inlcude
- erythrocytes
- leukocytes
- platelets
how do you distinguish elements of blood smear?
use of wright/geimsa stain
- nuclei stain purple
- erythrocytes stain pink
erythrocyte is also known as
Red blood cells (RBCs)
platelets are also known as
thrombocytes
leukocytes include:
- granulocytes
- agranulocytes
granulocytes include:
- neutrophils
- eosinophils
- basophils
neutrophils
- phagocytose (kill) bacteria
- increase in number in acute bacterial infections
eosinophils
- phagocytose (kill) parasites
- antigen-antibody complexes
- increase in number with parasitic infections
- secrete histaminase (inactivates histamine)
basophils
- involved in anticoagulation (inflammation)
- increases vascular permeability
- increase in number in allergic reactions
- release histamine
- similar to mast cells
agranulocytes include:
- lymphocytes
- monocytes
monocytes
- motile
- give rise to macrophages
- largest cells in blood
- non-staining cytoplasm
lymphocytes act in:
- B-cell (humoral) immunity
- T- cell (cellular) immunity
red blood cells
- biconcave disc
- contain hemoglobin
- strong cytoskeleton
- carbohydrates in glycoproteins at cell surface determine blood type
blood types:
A
B
AB
O
blood type A
antigens in RBC: A
antibodies in plasma: Anti-B
blood type B
antigens in RBC: B
antibodies in plasma: Anti-A
blood type AB
antigens in RBC: A and B
antibodies in plasma: NONE
blood type O
antigens in RBC: NONE
antibodies in plasma: Anti-A and Anti-B
blood type ______ is a universal __________ while blood type ________ is a universal _________.
AB, recipient
O, donor
what is sickle cell anemia?
a genetic defect that affects the hemoglobin subunits and manifests as tingling, pain, ischemia, hemolysis, and anemia
why is sickle cell anemia important?
it makes the person less susceptible to malaria infection
platelets
- play major role in blood coagulation
- produce von Willebrand factor, thrombosospondin, and platelet-derived growth factor
- often appear in clumps
- 10 day life
- no nucleus
platelet aggregation includes:
- primary aggregation
- secondary aggregation
- blood coagulation
primary aggregation of platelets
- disruption in the microvascular endothelium
- allow the platelet glycocalyx to adhere to collagen in the vascular basal lamina or wall
- thus platelet plug is formed
secondary aggregation of platelets
- platelets in plug release a specific adhesive glycoprotein and ADP
- induces further platelet aggregation
- increase the size of platelet plug
blood coagulation during platelet aggregation
- fibrinogen from plasma, von Willebrand factor, and other proteins released from damaged endothelium
- platelet factor 4 from platelet granules promote the cascade of plasma proteins giving rise giving rise to fibrin
- thus blood clot or thrombus
characteristics of granulocytes:
2 major granules:
1: lysosomes (azurophilic granules)
2: specific granules
- have polymorphic nuclei
- terminally differentiated
characteristics of neutrophils
- polymorphonuclear leukocytes
- help fight bacterial infection
- innate immunity
- initiate inflammation
- first line of defense
characteristics of agranulocytes
- not terminally differentiated
- lack specific granules but do contain azurophilic granules (lysosomes)
heparin
a sulfated GAG that acts locally as a coagulant
histamine
promotes increased vascular permeability and smooth muscle contraction
cytokines
polypeptides directing activities of leukocytes and other cells of immune system
anaphylaxis
a life threatening allergic reaction that can be stopped by use of epipen (epinephrine)
all lymphocytes are derived from:
bone marrow stem cells
B-cell lymphocytes
- differentiate and mature in bone marrow
- 10-15% of all lymphocytes
T-cell lymphocytes
- 60-80% of all lymphocytes
- defined by CD4+ and CD8+ and memory cells
antigen presentation leads to
activation of helper (CD4) and cytotoxic (CD8) and B lymphocytes
the bone marrow
- site of generation of RBCs, leukocytes, platelets
- mature blood cells have short lifespan and must be replaced
- cells arise in the yolk sac mesoderm
composition of bone marrow
- is a special type of connective tissue
- hematopoietic cells
- marrow adipose tissue
- supportive stromal cells
2 types of bone marrow
- red
- yellow
red bone marrow
- the actively hematopoietic tissue
- is abundant in prenatal life and in the young
- red due to erythrocytes and their precursors
yellow bone marrow
- a fatty replacement around ages 20-25
- relatively inactive
- mainly composed of adipocytes
all blood cells come from
pluripotent hemopoietic stem cells
what lineages of cells are produced from pluripotent hemopoietic stem cells?
myeloid and lymphoid stem cells
the myeloid lineage includes
precursor cells for
- erythropoiesis
- thrombopoiesis
- granulopoiesis
- monocytopoiesis
the lymphoid lineage includes
- B lymphocytes
- T lymphocytes
- natural killer cells
what promotes growth and differentiation throughout the developmental process?
- erythropoietin (EPO)
- colony stimulating factors (CSF)
- cytokines
- growth factors
myeloid cells include
- granulocytes
- monocytes
- erythrocytes
- megakaryocytes
cell size gets __________ as cells differentiate
smaller
megakaryocytes _____________ in size as they differentiate
increase
______________ _______________ are the cells that synthesize hemoglobin and then degenerate.
basophilic erythroblast
what does it mean to be terminally differentiated?
scheduled to die
terminally differentiated cells
RBCs and granulocytes
monocytes will
differentiate
lymphocytes
proliferate and differentiate
