Blood Flashcards
Function of red and yellow bone marrow
red forms blood cells
yellow is mainly stored energy as fat
functions of blood
gaseous exchange
transport of nutrients, antibodies, hormones, water, metabolic waste
blood components when centrifuged
what makes each up
plasma (55%) - water, proteins, electrolytes, gases
buffy coat (1%) - platelets, WBCs
haematocrit (45%) - RBCs
why are RBCs biconcave
disc shape facilitates gaseous exchange
more haemoglobin is closer to the plasma membrane
haemoglobin consists of
how many oxygen molecules can it carry
four polypeptide chains complexed with haem group
4 (one per haem group)
life cycle of RBCs
erythropoiesis starts in the bone marrow
erythrocytes are released and circulate for 120 days
spleen and liver macrophages break down old erythrocytes releasing bilirubin, iron, AAs
liver processes bilirubin into bile
small intestine excretes in faeces
kidney excretes bile in urine and releases EPO
antibodies present in A, B, AB and O blood groups
A: anti-B antibodies
B: anti-A antibodies
AB: no antibodies
O: anti-A antibodies
anti-B antibodies
anaemia
insufficient Hb within RBCs
reduced number of RBCs
sickle cell anaemia cause
RBC features
autosomal recessive single point mutation in beta globin gene
sickle shaped
more rigid and do not enter finer capillaries
fragile and break down easily
types of granulocytes
types of agranulocytes
granulocytes: neutrophil, eosinophil, basophil
agranulocytes: lymphocytes, monocytes
what are azurophillic granules
large lysosomes of neutrophils
nuclei of immune cells
neutrophils: polymorphonuclear
eosinophils: bilobed
basophils: bilobed
lymphocytes: round densely stained
monocytes: horseshoe (kidney) shaped
what do eosinophil granules contain
peroxidase, histamine, arylsulfatase, other hydrolytic enzymes
what do basophil granules contain
hydrolytic enzyme, histamine, heparin sulfate and slow reacting substance of anaphylaxis
types of T-lymphocytes and their role
cytotoxic T-cells: recognise and kill
helper T-cells release factors to activate B-cells, CTLs and macrophages
suppressor T-cells: supress activity of B-lymphocytes and immune response
what are precursors to macrophages
monocytes
precursors to platelets
cytoplasm of megakaryocytes
how are megakaryocytes formed and how is it different to other cells
endomitosis
DNA replication and karyokinesis same as mitosis but no cytokinesis
what are plasma lipoproteins
function
two main types
soluble complex aggregates of lipids with specialised proteins
deliver insoluble lipids from the tissues
HDLs: good cholesterol
LDLs: bad cholesterol
haematopoietic stem cells
common myeloid progenitor
common lymphoid progenitor
haematopoietic stem cells: give rise to CMPs and CLPs
common myeloid progenitor: give rise to RBCs, platelets, granulocytes and monocytes
common lymphoid progenitor: give rise to T and B lymphocytes
