Cells of the Blood Flashcards
What is the proportion of different cells in the blood?
55% Plasma
45% Erythrocytes
1% WBC and Platelets
What is the function of plasma?
Carries solutes and cells
What is the function of RBC?
Carry oxygen
What is the function of WBC and platelets?
Fight infection and form blood clots
What 2 types of cell derive from multi-potential haematopoietic stem cells?
Common myeloid progenitor and common lymphoid progenitor
What 4 types of cell derive from common myeloid progenitor cells?
Megakaryocytes, erythrocytes, mast cells, myeloblast
What derives from megakaryocytes?
Thrombocytes
What 4 types of cell derive from myeloblasts
Basophils, neutrophils, eosinophils and monocytes
What do monocytes become?
Macrophages
What 2 types of cell derive from common lymphoid progenitor cells?
Small lymphocytes and natural killer cells
What 2 types of cell derive from small lymphocytes
B lymphocytes and T lymphocytes
What are 4 features of RBC?
Contain Hb, are numerous, biconcave discs and have no nucleus to maximise space for oxygen transport
How long do RBC live for?
120 days
How are RBC removed from circulation?
By phagocytic macrophages in the spleen and the liver
What is erythropoiesis?
The production of RBC
Where does erythropoiesis occur?
Bone marrow
What is the precursor cell called?
Proerythroblast
How does a proerythroblast become a a reticulocyte?
Develops and ejects its nucleus
How long does a reticulocyte take to become a RBC?
Becomes a mature RBC after 1-2 days
How is the rate of maturation of into proerythroblasts increased?
Reduced oxygen delivery to the kidneys and other tissues cause the kidneys to secrete erythropoietin (EPO) which increases the maturation rate
What is red bone marrow and where is it located?
Highly vascularised connective tissue located in the axial skeleton, pectoral and pelvic girdles and proximal epiphyses of the humerus and femur
Where does hematopoeisis occur?
Red bone marrow
What is yellow bone marrow?
Mainly fat, it replaces red bone marrow as we age, but can be converted into red marrow in certain conditions such as severe bleeding
How would you distinguish between WBC?
Neutrophil-multilobed nucleus
Basophil-kidney shaped nucleus (gram +ve)
Eosinophil-gram -ve
Monocyte-large with big nucleus
Lymphocyte-nucleus is most of cell
What does a high neutrophil count indicate?
Infection
What does a high eosinophil count indicate?
Parasite, allergy, leukemia
What does a high lymphocyte count in CSF indicate?
Viral meningitis
