Physiology of Blood Cells and Haematological Terminology Flashcards
- Blood cells of all types originate in
bone marrow
all blood cells are ultimately derived from ….
multipotent haemopoietic stem cells
2 families of blood cells?
Lymphoid and Myeloid
What derives from myeloid stem cell precursors (4)
red cells, granulocytes, monocytes and platelets are derived
What derives from lymphoid stem cell precursors
B, T, and NK cells
what is essential for a stem cell to be able to do
Ability to self-renew and produce mature progeny
how is a stem cells Ability to self-renew and produce mature progeny achieved
through its ability to divide into 2 cells with different characteristics -> 1 stem cell, and 1 cell capable of differentiating into mature progeny
- Myeloid stem cell gives rise to ….
proerythroblasts
proerythroblasts give rise to…..
erythroblasts
erythroblasts give rise to…..
erythrocytes
difference between erythroblasts and erythrocytes?
erythroblasts (with nuclei)
erythrocytes (without nuclei)
what hormone stimulates Normal erythropoiesis
erythropoietin
where is erythropoietin synthesised from (2) and in response to what
- Erythropoietin is produced by the kidney (mainly) and liver (minorly), in response to hypoxia (or anaemia)
What renal cell produces Erythropoietin
juxtatubular interstitial cell
Life span of erythrocytes?
120 days
where are erythrocytes destroyed and by what
phagocytic cells (e.g. macrophages) particularly of the spleen, but also any tissue in the body
myeloblasts can give rise to …
granulocytes and monocytes
what’re granulocytes (3)
neutrophils, eosinophils and basophils
What cytokines are needed for granulocyte/monocyte synthesis
G-CSF, M-CSF, GM-CSF
Life span of neutrophils? what they do after this
- Survive 7-10 hours in blood before migrating to tissues
Main function of neutrophils
defence against infection; phagocytoses and then kills micro-organisms
what is the process of neutrophil migration into tissues called
diapedesis
what is diapedesis
the process of neutrophil migration into tissues
what controls and guides neutrophil migration
chemokine signals
Main function of eosinophils
defence against parasitic infection
Main function of basophils
role in allergic response
Main function of monocytes
- Spend several days in circulation but don’t really have that huge a role in the circulation
- Migrate into tissues where they develop into macrophages and other specialised cells (e.g. Kupffer cells) that have a phagocytic and scavenging function
- Macrophages also store and release iron when phagocytosing red blood cells
Anisocytosis means…
Red cells show more variation in size than is normal
Red cells showing more variation in size than is normal is known as …
Anisocytosis
POIKILOCYTOSIS means…
Red cells show more variation in shape than is normal
Red cells showing more variation in shape than is normal is known as …
POIKILOCYTOSIS
Examples of poikilocytes? (6)
spherocytes irregularly contracted cells sickle cells target cells elliptocytes fragments
MICROCYTOSIS means …
Red cells are smaller than normal
Red cells being smaller than normal is known as….
MICROCYTOSIS
MACROCYTOSIS means
Red cells are larger than normal
Red cells are larger than normal is known as….
Macrocytosis
Different types of macrocytes? (3)
round macrocytes, oval macrocytes or polychromatic macrocytes
HYPOCHROMIA means …
Describes red cells with a larger than normal central pallor (central pallor is usually one third of the diameter of the cell, due to the disk shape of the red cell; the centre has less haemoglobin content and concentration and is a flatter cell)
What word is used to describe red cells with a larger than normal central pallor
HYPOCHROMIA
2 examples of hyperchromic cells?
spherocytes and irregularly contracted cells
What is a spherocyte?
A hyperchromic cell that is approximately spherical in shape, resulting from loss of cell membrane without the loss of equivalent cytoplasm, such that the cell is forced to round up Can be caused by hereditary spherocytosis (defect in ability of cytoskeleton to bind the lipid bilayer membrane Bits of membrane break off)
A hyperchromic cell that is approximately spherical in shape, resulting from loss of cell membrane without the loss of equivalent cytoplasm, such that the cell is forced to round up …. ?
a spherocyte