Blood Flashcards
what are the different blood cells?
red blood cells, white blood cells and platelets
what are erythrocytes?
red blood cells
what are leucocytes?
white blood cells
what are thrombocytes?
platelets
what is plasma?
extracellular fluid
what is plasma made of?
water, electrolytes, organic molecules and plasma proteins
what organic molecules make up plasma?
glucose, fatty acids, glycerides, amino acids
what are the 4 plasma proteins?
albumins, globulins, fibrinogen and regulatory proteins
what is the function of albumin in plasma?
oncotic pressure and transport of lipids
what is the function of globulins in plasma?
transport of ions, hormones, lipids and immune functions
what is the function of fibrinogen in plasma?
key component of blood clot
what is the function of the regulatory proteins in plasma?
enzymes and hormones
what is the most abundant protein in plasma?
albumins
what does blood volume depend on?
an individuals size
what is the average blood volume for a male?
70ml/kg body weight
what is the average blood volume for a female?
60ml/kg body weight
what percentage of blood volume does the plasma make up?
55%
what percentage of blood volume do the blood cells make up?
45%
what is the shape of red blood cells?
biconcave disc shape
what does the shape of red blood cells allow?
gives large surface area relative to volume, permits rapid gas transfer across cell membrane, allows RBC to bend in narrow capillaries, enables RBC to expand to accommodate fluid in hypotonic solutions
where are RBCs formed?
in the red bone marrow
what is the average lifespan of a RBC?
120 days
what happens to the old RBCs?
they are removed from circulation and broken down by MPS system (spleen)
what happens to the breakdown products of RBCs?
they are recycled
what does haemoglobin break down to form?
globin - amino acid pool
haem - iron; biliverdin and bilirubin
what is the life cycle of bilirubin
it is conjugated in the liver and excreted as bile pigment
what is erythropoeisis
red blood cell formation
what are the stages of erythropoeisis?
proerythroblast - ERYTHROBLASTS (basophilic erythroblast - polychromatophilic erythroblast - normoblast) - reticulocyte - mature red blood cell
what regulates erythropoeisis?
erythropoietin
what happen during the development of a RBC?
reduction in cell size and regression of nucleus and an increase in haemoglobin content
what nutrients does the development of RBCs require?
folic acid and Vitamin B12 (for reduction in cell size and regression of nucleus) and iron (for increase haemoglobin content)
describe the events that lead to erythropoietin release
decreased RBC numbers - decreased oxygen delivery to cells - decreased oxygen to kidney - ERYTHROPOIETIN RELEASE - red bone marrow - increased RBC production
what are the functions of haemoglobin?
transport of oxygen and transport of CO2
what does the Hb-O2 dissociation curve show?
the transport of oxygen
in what forms is carbon transported around the body?
carbonic anhydrase, bicarbonate production, carbamino coumpounds
what type of protein chains is haemoglobin made of?
2 alpha and 2 beta
what is a haeme group of haemoglobin made of?
porphyrin ring and iron atom
how main haem groups make a haemoglobin molecule?
4
what are the white blood cells?
neutrophils, basophils, eosinophils, monocytes and lymphocytes
which white blood cells are granulocytes?
neutrophils, basophils, eosinophils
which white blood cells are agranulocytes?
monocytes and lymphocytes
what is the role of neutrophils?
acute inflammation, phagocytic and non-specific defence
what is the role of basophils?
circulating mast cells, produce heparin and histamine
what is the role of eosinophils?
involved in allergic reactions, defence vs parasites
what is the role of monocytes?
become macrophages, APCs
what is the role of lymphocytes?
cell mediated immunity (T cells) and humoral immunity (antibody producing B cells)
what are platelets derived from?
megakaryocytes
what do platelets do?
involved in haemostasis, release vasoconstrictors, form platelet plug, source of phospholipid for coagulation
what are the 2 types of antigens that erythrocytes carry on their membranes?
AB antigens and Rhesus (Rh antigen)
what determines a person’s blood group?
the presence or absence of the AB and Rh antigens
what antigens does a person with type A blood have?
anti-B
what antigens does a person with type B blood have?
anti-A
what antigens does a person with type AB blood have?
no antigens
what antigens does a person with type O blood have?
anti-A AND anti-B
what determines the positive/negative part of a persons blood group?
the rhesus antigen
what happens if a Rh- person gets given Rh+ blood?
they will develop anti-Rh antibodies but they will not affect the recipient because they have no Rh- antigen
what happens if an Rh- female conceives an Rh+ foetus?
some of the foetal RBCs can enter maternal circulation at birth, anti-Rh antibodies are formed and these can attack and haemolyse the RBCs of a subsequent Rh+ foetus causing haemolytic disease of the newborn
why can group O- blood be given to anyone?
because it is a universal donor
why can group AB people receive any blood?
it is a universal recipient
