W11- Lecture 57- Blood 1 Flashcards
what are the three functions of the blood
Transports: dissolved gasses, hormones, nutrients, heat & waste (lungs, liver, GI, kidneys, endocrine glands etc)
Regulation: pH- buffers, temperature (absorbing & blood flow) and osmosis (dissolved ions)
Protection: clot, WBC’s, antibodies, interferon’s and other proteins
what are the physical properties of blood ?
density temp colour % body mass/ volume sampled by
Denser and more viscous than water
38⁰C, slightly alkaline
When saturated with oxygen is bright red, unsaturated is dark red
8% of body mass 4-6 litres depending on gender & size
Blood volume and osmotic pressure is tightly regulated by hormones (aldosterone, ADH, anti natiuretic peptide)
Sampled by venipuncture with a torniquet
what is the white blood cell % of each
neutrophils 50-70% lymphocytes 20-30% monocytes 2-8 eosinophils 2-4 basophils- less then 1
what formed elements would you find in the blood ?
RBC’s
Platelets
WBC’s
name the granular and a granular leukocytes
Granular
Neutrophils
Eosinophils
Basophils
Agranular leuckocytes
T & B lymphocytes aka small
Monocytes
what is Haematocrit
male v female
what causes this difference
Volume taken up by RBC’s
Females 38-46%
Males 40-54%
Testosterone caused erythropoietin, produces RBC
what is Polycythemia
increased risk of
causes
65% or more Increased viscosity increases resistance, heart works harder. Increase blood pressure and stroke risk.
Causes include improper RBC production, tissue hypoxia, dehydration and blood
what is Haemopoiesis
where does it occur
= formation of blood cells
Occurs in red bone marrow
red bone marrow
where is it found in new borns ?
what happens here
In newborns all marrow is red, is converted to yellow over time
Process can be reversed under trauma
Home of pluripotent stem cells
in a bone marrow exam looking to diagnose disorders such as leukaemia what are you looking for ?
Morphology
granularity
Nuclear defects
count
Pluripotent stem cells in RBM produce what 2 subtypes of stem cells?
Myeloid stem cells & lymphoid stem cells
what do Myeloid stem cells develop into?
where ?
give rise to platelets, RBC, monocytes, neutrophils, eosinophils and basophils
in the red bone marrow
what do Myeloid stem cells develop into?
where ?
give rise to platelets, RBC, monocytes, neutrophils, eosinophils and basophils
Some myeloid stem cells differentiate into progenitor cells, others & the lymphoid stem
cells develop straight into precursor cells
in the red bone marrow
what is the difference between Progenitor cells and precursor cells
Progenitor cells cannot reproduce, they are committed to forming their designated cell type (CFU eg CFU-E)
Precursor cells (blasts) over several divisions develop into the actual formed elements of blood
what are the Medical uses of Haemopoietic growth factors
Recombinant growth factors
Erythropoietin for kidney disease
Granulocyte CSF for WBC formation after chemotherapy
Thrombopoietin for chemotherapy
Also used for clotting disorders & a range of neonatal disorders
Red Blood cells (erythrocytes)
produced per second ?
conc in blood
what % of co2 in body bound
can it transport NO + use
Produce 2 million RBCs per sec
Blood contains 5 million per μl
5-8% of CO2 in the body is bound physically to haemoglobin
Bind & carry NO for vasodilation and thrombotic control
how much oxygen does an adult use a min ?
An adult uses 0.25L oxygen per minute
describe the oxygen dissociation curve in terms of carbon
+ shifting of curve
In the lungs blood becomes more alkaline due to a loss in carbonic acid, the curve shifts to the left
In the capillaries carbon dioxide diffuses in from the tissue, the curve shifts to the right
Exercise creates acidic conditions due to lactic acid, creates the Bohr effect
describe the two confirmations of allosteric interactions
which one would you find in the
lungs
capillaries
2 confirmations;
High-affinity R
Low affinity T
lungs-R
capillaries- T
what are Ruptured RBC removed by ?
fixed macrophages
RBC life cycle
Macrophage in spleen
Glob in is broken down into constituent AA and used for protein synthesis
Heme – recycling Fe3+ moves to liver transported to where RBC production (into red bone marrow )
can recombine it with globin , vitamin b12 and erythropoietin
Makes RBC
Heme (getting rid of )
Converted into biliverdin(green) then bilirubin(yellow) in pancreas
Bilirubin into liver
Then into small intestine
Converted into urobilinogen in intestine (which can be excreted by kidney(yellow colour) )
Or urobilinogen can be converted into stercobilin which can be excreted (brown colour of poo)
Jaundice due to bilirubin
how can a Iron overload damage tissue
treatment
Fe2+ + Fe3+ bind to and damage cells
Plasma doesn’t normally contain free iron
Iron carrying proteins can be overloaded
Therapeutic – treatment lower iron diet and often blood donations
what is Erythropoiesis
+ explain
RBC production
RBC production starts in Red Bone Marrow with the precursor cell type pro-erythroblast
They divide several times, producing cells which make haemoglobin
Eventually they differentiate into reticulocytes, which eject their nuclei
They pass into the blood and differentiate into RBC
what can happen if Erythropoiesis doesn’t keep up with red cell demand
cause
Can lead to hypoxia
Can be due to anaemia or dietary deficiencies
Can be caused by circulatory problems
