Hematology- Haematopoiesis Flashcards
List the constituents of blood?
-plama( made of plasma proteins, globular and fibrinogen
- Buffy coat ( thrombocytopenia and leucocytes)
Erythrocytes
List the 5 types of white blood cells
Neutrophils, eosinophils, basophils ,lymphocytes and monocytes
Functions of each type
Neutrophils- phagocyytic effective against bacteria
Eosinophils- phagocytic antigen-antibody complexes. Increase antihistamines. Increase in allergies and parasitic infections
Basophils- promotes inflammation
Lymphocytes-primary specific immunity. B and t cells
Monocytes- served as antigen presenting cells, very effective in engulfing pathogens
List the functions of blood
- Transportation: o2 from the lungs to the cells of the body and co2 from the cells to the lungs
Carries nutrients from the gastrointestinal tract to the cells. Heat and waste products away from cells and hormones to other body cells
2.regulation: blood regulates ph through buffers
Adjust temperature through heat absorbing and coolant properties of it’s water content
- Protection: the clotting mechanism protects against blood loss
Certain phagocytic white blood cells protect against foreign pathogens
Define haemopoiesis
Process of the formation of Blood cellular components
What are the sites of haemopoiesis
- Yolk sac- 3rd week of gestation
2.liver- 2nd month
3.bone marrow cavitives- gradually, 3rd trimester - Bone marrow- postnatal
Monophyletic theory
Suggest that there is a common partent cell of all forming elements of blood
Dualistic theory
Suggest two sources of haemopoiesis: lymhoid and myeloid
Polyphyletic theory
Suggest different groups of Blood cells originate from different stem cells
List the cellular organization of haematopoiesis
Stem cells
Page it or ces
Precursor and effector
Talk about stem cells
1 totipotential
2. Resides in bone marrow
small amounts circulate the blood
3.dysfunction leads to a plastic anemia or certain types of leukemia
Talk about progenitor cells
1 lymphoid or myeloid
2.derived from totipotential stem cells
3.lymphoids give rise to mature lymphocytes and myeloids give to granulocytes , monocytes and platelets
Talk about precursor cells
First morphological identifiable cells
Erythroblasts- red blood cells
Myeloblasts- granulocytes
Monoblasts- monocytes
Lmyphoblasts- lymphocytes
Megakaryoblast-platelets
List the two types of bone marrow
- Medula ossium ruba (red marrow)
- Medula ossium flava (yellow marrow)
M:E ratio myeloid to erythroid ratio
Normal ratio?
Normally 3-4.1
Decreased m: e (hemolytic and megaoblastic anemias
Increased m:e ( leukaemoid reactions
Pathologic samples of bone marrow obtained by ………… and sites include……
Bone marrow biopsy and bone marrow aspiration
Sites include sterum and anterior abd posterior Iliac spines
What are haematopoietic growth factors?
Haematopoietics growth factors are glycoproteins hormones that regulate the proliferation and differentiation of h. Progenitor comes and the function of mature cells
Refered to as csf
List different growth factors , source and function
See lecture 1 slide 39.
Define extramedullary haematopoiesis
Normal blood cells outside the bone marrow
Define apoptosis
Programmed cell death;cells de grade for the body to eliminate unwanted/dysfunctional cells
List the 2 reasons for apoptosis
- Withdrawal of positive signal eg. (Il2)
- Receipt of negative signals eg. Increase level of oxidants( damage dna)
List 3 imducers of apoptosis
- Growth factors withdrawals
- Uv and gamma radiation
- Toxins
4 nutrients deprivation
What does CASPASES mean
And what is the purpose of it
. Cysteine asparate specific protease
Function- role in apoptosis is to cut of contact with surrounding cells
List the factors involved in erythropoesis
Erythropoietin and IL 3 , g csf
List the stages of erythropoesis
- Proerythroblast
- Basophilic erythroblast
- Polychromatophilic erythroblast
- Orthochromatic erythroblast
5.polychromatophil8c erythrocyte(reticulocyte) - Mature Rbc
Ineffective erythrocytes may occur in…..
- External blood loss
- Chronic inflammation
- Lack of erythropoietin
- Cytotoxic bone marrow injury
What is the formation of white blood cells called?
Leucopoesis
Review the formation of granulocytopoiesis
Lecture 1 pg 62
List the functions of white blood cells
Nuetrophils- localized response, acute inflammation
Eosinophils-anti parasitic hypersensitivity
Basophils- igE mediated hypersensitivity
