Blood Flashcards
what is the proportion of plasma in the blood
55%
what is the proportion of cells in the blood
45%
what are the formed elements of the blood
cells
what are the types of cells found in the blood
- erthyrocytes
- leukocytes
- thrombocytes
what are erythrocytes
red blood cells
what are leukocytes
white blood cells
what are thrombocytes
platelets
what is found in blood
- erythrocytes
- leukocytes
- platelets
- extracellular fluid
- water
- electrolytes
- organic molecules
- plasma proteins
what are the components of plasma
- extracellular fluid
- water
- electrolytes
- organic molecules
- plasma proteins
what are the organic molecules of plasma in the blood
glucose
fatty acids
glycerides
amino acids
what are the plasma proteins found in the blood
albumins
globulins
fibrinogen
regulatory proteins
which is the main plasma protein
albumins
what proportion of blood plasma proteins is albumins
60%
what proportion of blood plasma proteins is globulins
35%
which plasma protein takes up 35% of all plasma proteins
globulins
what proportion of blood plasma proteins is fibrinogen
4%
what proportion of blood plasma proteins is regulatory enzymes
1%
what are albumins
plasma proteins that function in oncotic pressure and transport of lipids
what is oncotic pressure
a type of osmotic pressure that functions to pull blood back through the capillary system
what is the function of globulins
transport of ions, hormones and lipids as well as immune functions
what is the immune function of globulins
they form immunoglobulins which function to serve as antibodies, and can be observed in the saliva as plasma overflow.
what is the function of fibrinogen
they form the key component of blood clots
what are the regulatory proteins found in the blood plasma
enzymes and hormones
what does blood volume depend on
the individuals size
what does blood volume differ between
males and females
average blood volume of males
70ml/kg of body weight
average blood volume of females
60ml/kg
what proportion of blood volume is taken up by plasma
55%, but the range is 46-63%
what is the range of proportion that cells take up in the blood
37-54%, average is 45%
which type of blood cell is most abundant, taking up more than 99%
red blood cells
describe the shape of red blood cells
biconcave disc
what is the diameter of red blood cells
6-8 micrometers
why are red blood cells shaped as biconcave
- large surface area to permit rapid gas transfer across cell membranes
- allows the cell to bend in narrow capillaries
- enables expansion to accommodate fluid in hypotonic solution
which red blood cells are more fragile in hypotonic solutions
older ones
which gases are transferred across red blood cell membranes
oxygen and carbon dioxide
why can the blood film in histological viewing appear like a halo
due to the sectioning level
where in the body are red blood cells formed
the red bone marrow
where is red bone marrow located in the body
- top and bottom ends of long bones
- hip bones
- skull
- sternum
what is the most ideal area to take samples of red bone marrow
the hip
what is the average lifespan of a red blood cell
120 days
how are old red blood cells removed from the circulation to be broken down
by mononuclear phagocyte system, mainly from the spleen
what happens to the breakdown products of the old red blood cells
they are recycled to be used for the production of the next generation of red blood cells
whereis bilirubin conjugated
in the liver
how is bilirubin excreted
as bile pigment
what is the reticuloendothelial system
part of the immune system that is now known as the mononuclear phagocyte system that functions to remove old blood cells, form bile pigments and plasma proteins, and store iron
function of the mononuclear phagocyte system
- help form new blood cells
- remove old red blood cells
- form bile pigments and plasma proteins
- help store iron
what is transferrin
a glycoprotein that mediates the transportation of iron
where are macrophages found in the body
spleen
liver
bone marrow
what are the breakdown products of red blood cells
heme
biliverdin
bilirubin
iron
amino acids
where do heme, biliverdin and bilirubin go once they have been broken down from the old red blood cells
the liver to form bilirubin
where does iron go as the breakdown product of red blood cells
transported in circulation by transferrin to be taken to the bone marrow for new red blood cell formation
where do the amino acids go as breakdown products of old red blood cells
bone marrow for new red blood cell formation
what happens once new red blood cells are formed in the bone marrow
they are released into circulation, where 90% go on to function as normal red blood cells and 10% undergo haemolysis and go to the kidneys and liver
where do some bilirubin derived products go
some to the bile in the duodenum and some to be elimited in the urin alongside old haemoglobin
which bilirubin derived products are releasde into the faeces
stercobilins
what gives urine the yellow colour
urobilins
what is erythropoietin
the hormone that regulates red bone cell formation
what are the stages to red bone cell formation
day 1 - proerthyroblast
day 2 - basophilic erythroblast
day 3 - polychromatophilic erythroblast
day 4 - normoblast and ejection of nucleus
day 5 -7 - reticulocyte
when do reticulocytes become erythocytes
once they have entered the circulation and matured
what is the name given to the red blood cells at the initial stage of formation
proerythroblast
what happens to the red blood cells during their formation
- reduction in cell size
- ejection of the nucleus
what is required for the development of red blood cells
folic acid, vitamin b12 and iron
what is iron used for
increasing haemoglobin content and therefore involved in oxygenation of body tissues
what is the process of erythropoiein function
- decrease in red blood cell numbers
- decrease in oxygen delivery to cells
- decrease in oxygen delivery to the kidney
- this is detected by the kidney and erythropoietin is released
- makes its way to the red bone marrow
- red blood cell production
when will the kidney produce more red blood cells
when there is hypoxia
what kind of molecule is erythropoietin
a glycoprotein cytokine, and a hormone
what does the Hb-O2 dissociation curve demonstrate
the transport of oxygen
what is carbonic anhydrase
protein that catalyses the conversion of dissolved bicarbonates and carbon dioxide
what is involved in the carrying of carbon dioxide by the haemoglobin
- carbonic anhydrase
- bicarbonate production
- carbamino compounds
the main functions of haemoglobin
transport of oxygen
transport of carbon dioxide
what kind of protein is haemoglobin
globular
what is the molecular weight of haemoglobin
68000
describe the structure of haemoglobin
two alpha and two beta chains arranged diagonally across each other
what is found in the haeme groups in each haemoglobin molecule
porphyrin ring and iron
how many heme groups per Hb molecule
four
what does iron function to do in carrying oxygen
reversibly binding oxygen
how many Hb molecules are there per red blood cell
200-300
what is the structure of a porphyrin ring
four carbons and one nitrogen
what does oxygen saturation increase with
increases in partial pressure of oxygen
what is the maximum saturation of oxygen possible in haemoglobin
98%
why can haemoglobin never be 100% saturated with oxygen
because it must also carry carbon dioxide
what are the two different types of leukocytes
granulocytes and agranulocytes
what are the granulocytes of the blood
neutrophils
basophils
eosinophils
what aregranulocytes of the blood
monocytes
lymphocytes
what is the difference betweeen granulocytes and agranulocytes
granulocytes have granules in the cytoplasm
which type of leukocyte is the most abundant in the blood
the neutrophils
which type of leukocyte takes up 50-70% of the blood white blood cells
neutrophils
which type of leukocyte takes up 1% of the leukocytes
basophils
which type of leukocytes take up 2-4% of the leukocytes in the blood
eosinophils
which type of leukocytes take up 2-8% of the leukocytes in the blood
monocytes
which type of leukocytes take up 25-30% of leukocytes in the blood
lymphocytes
what is the function of neutrophils
acute inflammation, phagocytic. they have non specific defence
what is the function of basophils
circulating mast cells that produce heparin and histamine
what is the function of eosinophils
involved in allergic reactions and defence against parasites
what is the function of monocytes
these become macrophages and function in antigen presenting
what is the function of lymphocytes
cell mediated immunity and humoral immunity
what do B lymphocytes do
they produce antibodies for humoural immunity
what do T lymphocytes do
these function in cell mediated immunity
describe the structure of neutrophils
multi lobed nucleus with condensed chromatin
12-14 micrometers in diameter
lifespan of a few days
basophilic
few organelles
describe the structure of eosinophils
- 12-17 micrometers in diameter
- larger than neutrophils
- bi lobed nucleus
- further segments with age
- eosinophilic cytoplasm
what do eosinophils maintain
inflammatory responses like allergic rhinitis
describe the structure of basophils
14-16 micrometers
bilobed nucleus
basophilic granules
formed in bone marrow
what is the least common leukocyte
basophils
what are the largest leukocytes
monocytes
how many leukocytes in the peripheral blood are constituted of monocytes
2-10%
how many times do monocytes circulate before they migrate into tissues
for three to four days
what may monocytes mature into
tissue resident macrophages with extended lifespans.
describe the structure of monocytes
- large, eccentrically placed nucleus
- stains less intensely with more open chromatin
- deep indentation in the nucleus near to the centre of the cell
- horseshoe shaped nucleus
- can have 2 or 3 nuclei
- cytoplasm stains pale greyish-blue
- small, purple stained lysosomal granules and cytoplasmic vacuoles
which type of leukocyte has a horse shoe shaped nucleus
monocytes
which type of leukocyte has a bilobed nucleus
basophil and eosinophils
which type of leukocyte has a nucleus that can further segment with age
eosinophils
where are monocytes found
circulating in the blood
function of monocytes
- respond to chemotaxic signals from damaged tissue, microorganisms and inflammation
- migrates into the damaged tissues and differentiates into macrophages
which type of leukocyte comprises of 20-50% of white cells in the circulation
lymphocytes
what size are most circulating lymphocytes
6 to 9 micrometers
what are most circulating lymphocytes called
small lymphocytes
what are the other type of lymphocytes that make up 3% of all lymphocytes
large lymphocytes
what is the size of large lymphocytes
9 to 20 micrometers
what are platelets derived from
megakaryocytes
what are megakaryocytes
large bone marrow cells
what are platelets
cellular fragments roughly 2 micrometers
what are platelets involved in
haemostasis
how do platelets regulate haemostasis
they release vascoconstrictors to form a platelet plug
what is used by platelets to regulate haemostasis
thromboxane A2 is the vasoconstrictor, and platelet factor is used for coagulation
what is thromboxane A2
a vasoconstrictor released by platelets for haemostasis
what is the normal platelet count
150-400 x 10^9 litre
what are antigens
substances that can cause an immune response
what is found on the membranes of erythrocytes
antigens
why are the antigens on the membranes of erythrocytes important
in related to blood transfusions as they characterise an individuals blood type depending on the antibodies present in their blood and the presence of rhesus factor
what determines a person’s blood type
presence or absence of antigens on their erythrocyte’s membrane
what is the average red blood cell count for a child
4.8 x10^12 per litre
what is the average red blood cell count for an adult female
4.8x10^12 per litre
what is the average red blood cell count for an adult male
5.4x10^12 per litre
what is the packed cell volume for a child
0.4
what is the packed cell volume for an adult female
0.42
what is the packed cell volume for an adult male
0.47
what is the haemoglobin count per litre for children
134 grams
what is the haemoglobin count per litre for adult female
138 grams
what is the haemoglobin count per litre for an adult male
158 grams
what is the packed cell volume
proportion of blood that is made up of cells
what is the haematocrit
the ratio of blood cells to blood volume, the same as the packed cell volume
what are the possible blood types
A
B
AB
O
what are the most common blood types in the UK
A - 42%
O - 44%
what is the red blood cell antigen on blood type A
A
what is the red blood cell antigen on blood type B
B
what is the red blood cell antigen on the blood type AB
both A and B
what is the red blood cell antigen on the O blood type
has neither antigens
what does O negative blood type mean
the patient has neither A or B antigens on their red blood cells, and are rhesus negative
what are the genotypes for blood type A
AA and AO
what are the genotypes for blood type B
BB or BO
what are the genotypes for blood type AB
AB
what are the genotypes for blood type O
OO
what are the natural antibodies for blood type A
Anti-B
what are the natrual antibodies for blood type B
Anti-A
what are the natural antibodies for blood type AB
there are none
what are the natural antibodies for blood type O
Anti A and Anti B
how are the antigens attached the surface of the red blood cells
they attach to the oligosaccharide chains that project above the red blood cell surface
what attaches the oligosaccharide chains to the red blood cell surface
the proteins and lipids liying in the red blood cell membrane
how do the antibodies work
they bind to the red blood cells and activate the complement cascade, which lyses the red blood cells while they are still in the circulation.
what are the naturally occurring antibody types in the blood
IgG and IgM
what percentage of people are rhesus positive
83%
what percentage of people are rhesus factor negative
17%
what is the antigen for rhesus positive red blood cells
Rh or D
what are the genotypes for rhesus positive red blood cells
DD or DO
what can happen if an Rh negative person receives Rh positive blood
they will develop anti Rh antibodies but this will not affect the recipient because they have no Rh antigen
what is the issue with rhesus negative individuals developing rhesus positive antibodies through contact with rhesus positive blood
if an rh negative female conceives an rh positive foetus, some of the fetal red blood cells can enter maternal circulation at birth and form anti rh antibodies and these can attack and haemolyse the red blood cells of the subsequent rhesus positive foetus.
what should occur with donor blood
it should be appropriately cross matched so that a group A positive person is give a positive blood
why are there fatty acids in the blood
products of digestion
how does fibrinogen form a blood clot
it is converted to fibrin when you have a blood, which is the active form of fibrinogen, and this forms the clot
what does blood volume depend on
age and gender
what is the amount of blood that can be lost before you feel the symptoms
15-20%
what happens once there is severe blood loss
low heart rate and reduced blood pressure
what is special about red blood cells
they do not have a nucleus
why must red blood cells be small and biconcave in shape
the capillaries they must pass through are 3 or 4 micrometes in length, and they must be able to bend through
what is the lifespan of a red blood cell
120 days
what does the spleen do to red blood cells
they break down old red blood cells
which organ in the body is responsible for breaking down old red blood cells
the liver
what is heme
the iron component in red blood cells
how many months is the life span of a red blood cell
four
where do the biliary secretions open into
the second portion of the duodenum
what proportion of red blood cells produced are faulty and must undergo haemolysis
10%
what can an altered colour in the faeces indicate
an issue in the liver or bone marrow of the patient
what is the name of the hormone that controls red blood cell production
erythropoietin
what does polychromatic mean
there is lots of chromatin in the nucleus
at what stage of production do the red blood cells lose their nucleus
day four
how long can iron be stored in the liver before we begin to feel the symptoms
3-4 months
what are the symptoms of iron deficiency
lethargy and fatigue
what is the active form of iron
Fe2+
when does oxygen capacity of haemoglobin in an individual reach its best ability
at birth of the individual
what increases the percentage of oxygen saturation in the haemoglobin
the pressure of oxygen
why were athletes taking erythropoietin to cheat
because the theory was that if there was greater oxygen content there would be greater muscle vascularisation and therefore enhanced performance, however this is not the case
how many different types of leukocytes are there
5
what does an increase or decrease in white blood cell count indicate
infection or another pathology
what do coughs and flus do to the antibody count in the blood
increase the count of neutrophils, which will ingest the bug to attempt to digest them
how do lymphocytes appear in the mucosa
as dark dots
which antibodies are responsible for chronic infections
lymphocytes
which white blood cells are responsible for acute infection responses
the neutrophils
which white blood cells respond to hayfever and other allergies
eosinophils
what do epi pens contain
adrenaline, which stimulates circulation
what are the symptoms of a true allergic reaction
swelling of the face and neck, difficulty breathing and swallowing
which allergy type is the most severe
type 1 allergies
which white blood cells have large nuclei that dominate most of the cytoplasm
basophils
what is haemostasis
blood clotting
what is PVC
packed cell volume
how does the PVC in children compare to the PVC in adults
they are the same
how does oxygen carrying capacity in children compare to that in adults
less efficient
why is it important that the antigens on the erythrocytes are not matched with the antibodies in the blood
the antibodies will attack the red blood cells and degrade them if this happens
what does haemolytic disease in newborns lead to
organ failure
what can be done to ensure that haemolytic disease does not occur in foetuses
provide anti rhesus medication to the mother
why can o type blood be used as a universal donor if there are no other availabilities
because there is nothing on the o type blood cells that can be attacked
