Blood & blood cells Flashcards
(26 cards)
What are erythrocytes?
RBC
What is the function of RBC?
respiratory transport of O2 (via haemoglobin) and CO2 (via carbonic anhydrase)
What mechanism is erythrocyte production?
negative feedback
Give the mechanism for erythrocyte production if there is low O2
1) low O2
2) bone marrow stem cells increase erythropoietin production (as does testosterone)
3) increased erythropoiesis
4) increased number of erythrocytes
5) increase in blood Hb levels
6) increase blood O2
What is erythrocyte life span?
120 days
Where are erythrocytes produced and what is the name of immature erythrocytes and what do they contain?
bone marrow, reticulocytes, ribosomes
How are ribosome removed fro reticulocytes?
reticulo-endothelial system in spleen
What type of binding is haemoglobin O2 binding? Explain the mechanism
co-operative binding
low affinity for O2 due to conformational shape of global molecules, 1st O2 binding breaks conformation and opens up structure
Name the key red cell parameters
conc haemoglobin, haematocrit, red cell count
What is haematocrit?
packed cell volume
What is the equation for MCV?
haematocrit/red cell count
Name the 3 types of anaemia
microcytic, normacytic, macrocytic
What is anaemia?
low blood haemoglobin concentration
Give the characteristic of microcytic anaemia and what it is due to
small MCV
gradual blood loss or Fe deficiency
failed haemoglobin synthesis
Give the characteristics of normacytic anaemia and what it is due to
normal MCV
acute blood loss or low haemoglobin concentration
Give the characteristics of macrocytic anaemia and what it is due to
large MCV - function normally
folic acid deficiency, vit B12 deficiency
DNA synthesis/cell division failed, fewer but larger RBC
Name the 3 types of leukocytes
polymorphonuclear granulocytes, lymphocytes, monocytes
Give the 3 types of polymorphonuclear granulocytes
neutrophils, eosinophils, basophils
Give the characteristics of polymorphonuclear granulocytes and what they do
segmented nucleus, cytoplasmic granules
adhere to blood vessels in infected area and migrate to tissue, engulf/digest microorganisms, release inflammatory mediators
How do B-lymphocytes assist immunity?
produce antibodies that that bind to antigens which assist phagocytosis by:
1) precipitation or agglutination
2) opsonisation (coating in antibody)
3) neutralisation (prevent attachment of micro-org to tissues)
What do activated T-lymphocytes do?
release chemotaxins to attract macrophages, release lymphotoxin (kill cells), release interferon (kill viruses)
Describe the characteristics of monocytes and what they do
single horse shoe nucleus
become macrophages in tissue, engulf micro-org/tissue debris/dead polymorph, secrete inflammatory mediators and stimulate angiogenesis
What is the size of a platelet?
2-3 micrometers
What is platelet life span?
8-10 days
