Blood Flashcards
What are the cells in blood?
red blood cells (erythrocytes)
white blood cells (leucocytes)
platelets (thrombocytes)
What is plasma made of?
extracellular fluid
water, electrolytes, organic molecules
plasma proteins
What are the plasma proteins found in the blood and what is their function?
fibrinogen (blood clotting)
albumins (oncotic pressure, transport of lipids)
globulins (transport of ions, hormone and lipids, immune function)
regulatory proteins (hormones and enzymes)
What is the average BV for a male?
70ml/kg
What is the average BV for a female?
60ml/kg
What makes up the majority of blood, plasma or cells?
plasma
What cells are most abundant?
red blood cells (erythrocytes)
What is the structure, function, production site and turnover of RBCs?
biconcave disc shape - large surface area relative to volume
rapid transport oxygen from lungs to tissues and carbon dioxide from tissues to lungs
produced in bone marrow
120 day turnover
What happens to ‘old’ RBCs?
old and damaged RBCs are removed from circulation and broken down (haemolysed) via the MPS system (mononuclear phagocyte system) in the spleen, liver and bone marrow
breakdown products from haemoglobin (heme (iron), amino acids) are recycled
What is iron transported by In the bloodstream?
transferrin - glycoprotein that mediates the transportation of iron
What is the fate of the heme group once RBCs have been haemolysed and iron is removed?
heme is converted to biliverdin (a green compound)
biliverdin is then converted to bilirubin which is released into the bloodstream
bilirubin attaches to albumin plasma protein and is transported to the liver for excretion in bile
What does a build-up of bilirubin (through blocked ducts or inadequate absorption/excretion) cause?
bilirubin diffuses into peripheral tissues causing a yellow appearance of skin and eyes called jaundice
Where are RBCs (erythrocytes) formed?
bone marrow
What is the process of erythrocyte formation called?
eyrthropoesis
What hormone regulates eyrthopoesis?
eyrthopoietin
What are the stages of RBC development?
day 1 -proerythroblasts
day 2 -give rise to basophilic erythroblasts
day 3 -give rise to polychromatophilic erythroblasts
day 4 -normoblast
day 5 -reticulocyte
into red blood cell
What day in erythopoiesis is the nucleas removed?
4
What happens during development?
regression of nucleus
reduction of cell size
What is required for eyrthopoesis?
folic acid, vitamin b12, iron
What is low blood oxygen called?
hypoxia
Where is erythropoietin produced?
kidney
What is the function of haemoglobin?
oxygen transport
How many haem groups in haemoglobin?
4
What type of protein is haemoglobin?
globular
What is Hb-F and how does it differ from normal Hb
fetal haemoglobin which binds oxygen more readily than adult
How many oxygen molecules can bind to Hb?
4
Where does oxygen bind to?
iron atom on haem group
What is one method of treatment for sickle cell anemia?
the production of fetal hemoglobin can be stimulated in adults by the administration of drugs such as hydroxyurea or butyrate.
What does oxygen bind with haemoglobin to form?
oxyhaemoglobin
What factors alter the Hb-O2 dissociation curve?
temperature, ph, CO2
What is the difference between argranulocytes and granulocytes?
argranulocytes do not have granules in cytoplasm whereas granulocytes have granules in cytoplasm
What are the WBC granulocytes?
neutrophils, basophils, eosinophils, mast cells
What tissue is plasma referred to as?
fluid connective tissue
What are the WBC argranulocytes?
monocytes, lympocytes
What is the function of neutrophils?
acute inflammation, non-specific defence, phagocytic
What is the function of basophils?
produce histamine and heparin
What is the function of eosinophils?
defence against parasites, allergic reaction
What is the function of monocytes?
become macrophages, antigen presenting cells
What is the function of lymphocytes?
cell-mediated immunity (T cells)
humoral immunity (B cells)
What cell are platelets derived from?
megakaryocytes (large bone marrow cells)
What is haemostasis?
a process to prevent and stop bleeding, meaning to keep blood within a damaged blood vessel via coagulation
What is coagulation?
clumping
What is the vasoconstrictor that platelets release?
thromboxane
What do erythrocytes sometimes carry on their membrane and what does this classify?
antigens and the blood type
What are the blood types?
O, AB, A, B
What antigens and antibodies do the blood contain?
A = A antigen, B antibody
B = B antigen, A antibody
O = no antigen, both antibodies
AB = both antigens, no antibodies
What is the PCV (haemotocrit) ?
packed cell volume
What does a low PCV indicate?
anemia
What are the other antigens that can be present?
Rh
What happens in haemolytic disease?
Rh - woman has child with Rh + man
first pregnancy foetus is Rh+ and Rh antibodies are formed in mother
second pregnancy foetus is Rh+ and RBCs are attacked and haemolysed
Who Is a universal donor?
O-
Who is a universal recipient?
AB +
What is the packed cell volume?
blood volume occupied by red blood cells (erythrocytes)
What is the packed cell volume as a % called?
haematocrit
Why is it that females PCV is lower?
- Androgens (testosterone) stimulate RBC production, and men have higher androgen levels than women.
- Women of reproductive age have periodic menstrual losses
What color do erythrocytes go when hemolysis occurs?
the solution goes from cloudy to a red transparent color as the RBC rupture and release hemoglobin
What solution makes RBC rupture?
hypotonic
Why does detergent cause RBC to rupture?
detergent dissolves lipids in the phospholipid bilayer of blood cells
Why does hemolysis occur in RBC put in a urea solution but not in a sucrose solution?
sucrose is too big to fit through the membrane whereas urea is a lipid soluble small molecule which can pass through the membrane
