blood as a transport system Flashcards
what is in plasma
- dissolved organic and inorganic (inorganic eg ions)
- plasma proteins
what are the plasma proteins
- albumins
- globulin
- fibrinogen
what is serum
plasma but without the clotting proteins
what’s in blood cells
- erythrocytes
- leucocytes
- platelets
what is most of the plasma made up of
water
what does albumin do
pH buffer and osmotic pressure
what do globulins do
binding proteins and antibodies
what are the clotting proteins
prothrombin and fibrinogen
what nutrients are in the plasma
glucose, fatty acids, amino acids, cholesterol, vitamins
what are erythrocytes
red blood cells
what is the life span of erythrocytes
short, only last about 120 days
where are erythrocytes synthesised
in red bone marrow by process called erythropoiesis
what filters rbc’s
the spleen and the liver
what does erythropoietin trigger
differentiation of stem cells to erythrocytes
what is the shape of the erythrocytes and why
biconcave disk in shape with a flexible membrane
have to be able to fold to fit through capillaries
do erythrocytes have organelles or nucleus
no
no DNA, RNA (so no division of mature RBC’s)
what enzymes are in erythrocytes
- glycolytic enzymes
- carbonic anhydrase
what does haemoglobin do
binds reactive oxygen molecules
what is oxyhaemoglobin
when oxygen is bound to IRON
what is deoxyhaemoglobin
no oxygen bound to IRON
what is carbaminohaemoglobin
when carbon dioxide is bound (to polypeptide chain)
what is required for blood processes
DPG
what is required for erythrocyte production
- iron
- folic acid
- vitamin b12
what is vitamin b12 needed for
DNA replication, thus cell proliferation
what can cause iron deficient anaemia in women
periods
what does insufficient erythrocyte count lead to.
- haemorragic anaemia
- haemolytic anaemia
- aplastic anemia
what is haemorrhagic anaemia
loss of blood from bleeding (wound, ulcer etc)
what is haemolytic anaemia
erythrocytes rupture (haemoglobin/transfusion problems, infections)
what is aplastic anaemia
red marrow problems (cancer treatment, marrow disease etc)
what is iron-deficient anaemia
low iron levels
caused by diet, absorption, bleeding
GI conditions can cause malabsorption
what is pernicious anaemia
low vit b12
caused by diet, intrinsic factor for vit b12 absorption)
what can cells that make HCl- also do
make intrinsic factor, damage to these cells means dietary b12 can’t be absorbed
what is MCH
estimation of haemoglobin amount in ONE red cell
what is MCV
mean cell volume
what causes microcytic hypochromic anaemia
caused by iron
low MCV and MCH
what causes normocytic, normochromatic anaemia
acute blood loss
haemolytic
bone marrow aplasia
bone marrow infiltration
normal MCV and MCH
what causes microcytic, hypechromic, megablastic anaemia
low b12
has high mcv and mch
what does the spleen do
filter and remove old erythrocytes
what does the liver do
metabolise byproducts from breakdown of erythrocytes
what is iron recycled for
the synthesis of new haemoglobin
how is iron transported in the blood
bound to transferrin and transported mainly to the red bone marrow
how is iron stored
bound the ferritin in the liver, spleen and small intestines
what do spleen macrophages do
filter blood by phagocytosis of old fragile RBCS
(mechanisms or recognition (T antigen exposure))
what happens after blood is filtered
haemoglobin is then catabolised and the iron is removed
haeme is converted into bilirubin
what happens to bilirubin
it is released into the blood and travels to the liver for further metabolism
what happens to products of bilirubin catabolism
they are secreted in bile to the intestinal tract or released into the blood and excreted in the urine
what are granulocytes
they contain membrane bound granules
what do neutrophils do
destroy and ingest bacteria
characteristics of neutrophils
- most numerous wbc
- defensives (antibiotic like proteins)
- polymorphonuclear
- causes lysis of infecting bacteria/fungi
- high poly count (likely infection)
characteristics of eosinophils
- only 1-4% of all leukocytes
- two-lobed, purplish nucleus
- granules with digestive enzymes
- phagocytose antigens and antigen/antibody complex
basophils characteristics
- rarest of all leukocytes
- deep purple U or S shaped nucleus
- basophilic granules with HISTAMINE
- related to mast cells of connective tissues
- both release histamine with IgE signal
what are agranulocytes
WBCs without granules in cytoplasm
ie no membrane bound granules
what do T lymphocytes do
found in thymus
respond against virus infected cells and tumour cells
what do B lymphocytes do
found in bone
differentiate into different “plasma cells” which each produce antibodies against different antigens
what do monocytes do
differentiate to become macrophages
serious appetites for infectious microbes largest of all leukocytes
