RBCs (Exams 1-2) Flashcards
What is the average size of RBCs?
8 um
What are normal physical characteristics of RBCs?
1/3 central pallor (pale center) | highly negative charged | disc-shaped with bi-concavity
What function does the negative-charge characteristic of RBCs serve as?
prevents clumping with each other = will not clot in vessels
What function does the bi-concavity characteristic of RBCs serve as?
allows for easy flow in capillaries
What characteristics do old RBCs have?
round shaped (no bi-concavity) | less negative charge | metabolism decreases
Are RBCs supposed to be nucleated or not? Where and/or when would they be nucleated?
nucleated when in the bone marrow or when they are not normal = indicates disease (such as anemia) | nucleus is removed once RBC matures
Why are RBCs safe to transfuse?
does not proliferate because not nucleated
What are the 5 types of anemia?
pernicious | hemolytic | sickle cell | thalassemia | polycythemia
What is polycythemia?
too many RBCs
Where does erythropoiesis mostly occur?
always in BM
What are the 6 stages of erythropoiesis?
rubriblast > prorubricyte > rubricyte > metarubicyte > reticulocyte > erythrocyte
What stage(s) of erythropoiesis is the chromatin fine?
rubriblast and prorubricyte
What stage(s) of erythropoiesis does the chromatin begin to condense?
rubricyte
What stage(s) of erythropoiesis does the nucleus get spit out?
metarubricyte
Why is having nucleated RBCs not good in circulation?
not much Hb = cannot carry O2 well
What stage(s) of erythropoiesis is the Hb produced?
reticulocyte
What are characteristics of reticulocytes?
bigger than RBC | can be in circulation | contains some basophilic stippling | no nucleus
What do reticulocytes in circulation indicate?
BM is hyperplastic and M.E ratio is low | body compensating for lost of RBCs
What occurs if there are nucleated RBCs in circulation? Why does this happen? What organ is affected first?
leads to hypoxia because have no Hb = they are not good O2 carriers | brain is first affected
What is the lifespan of RBCs?
~120 days
What are the granules seen in reticulocytes?
ribosomes and RNA needed to code and produce Hb
What is the function of reticulocytes?
produce Hb
What will happen to the RNA and ribosomal products once it matures into the full erythrocyte?
will get disintegrated
What aspect of RBC (other can chromatin, shape, nucleus, and size) can determine the maturity of the RBC?
color (blue/blue-ish = not 100% mature)
What dye does the Hb pick up when stained?
eosin
What are the 5 differences reticulocytes have that RBCs don’t?
lipid synthesis | RNA present | Hb synthesis | protein synthesis | mitochondria and metabolism
What is the negative charge on RBCs called?
zeta potential
Why or how is it possible for the shapes of RBCs to change?
cell membrane = very malleable since the inside content of RBCs is mostly water
How can an RBC become an echinocyte? Is this reversible or irreversible?
when the RBC is subjected under high salt concentration = water will come out due to salt concentration gradient | reversible, just make solution isotonic
What is an echinocyte also called (2 other terms)?
Burr cell | crenated cell
Other than being created, how will RBCs in hypertonic solution interact with other RBCs and why?
will stack up because salt (or protein) is neutralizing the (-) charge on RBC
Will you see agglutination in a patient with extreme diarrhea? Why or why not?
Yes since there’s a lot of proteins in the plasma due to extreme loss of water = plasma is hypertonic
What is anisocytosis?
RBC size not normal
Why is it important to know the Hb content in RBCs?
will dictate the O2 carrying capacity | low Hb = not good O2 carrying capacity
What is poikilocytosis?
RBC shape is different, not normal
What is poikilocytosis due to?
irreversible alternation of the RBC cell membrane
What is required for an RBC to maintain its normal shape?
ratio of proteins and carbohydrates need to be equal
What is basophilic stippling?
fine or aggregated blue granules in RBC; indicates immaturity of cell
What are the aggregates seen in basophilic stippling?
ribosomes, mitochondria, RNA
What stain is used to detect basophilic stippling?
Wright stain
What are Pappenheimer bodies?
coarse blue iron granules (siderotic granules)
What stain is used to detect Pappenheimer bodies?
Prussian blue
What are Howell-Jolly bodies?
purple mass = nuclear remnants containing chromosomes
What stain is used to detect Howell-Jolly bodies?
Wright stain
What are Heinz bodies?
purple mass of denatured Hb
What can cause Heinz bodies to form?
plasma pH | infection | RBC not functioning right | diseases and malignancies
What stain is used to detect Heinz bodies?
crystal violet or new methylene blue stain | doesn’t stain with Wright
What are Cabot Rings?
thread-like structure in oval shape or “8” | remnants of microtubules
What stain is used to detect Cabot Rings?
Wright stain
What is normachromia?
1/3 central pallor | heavy HB concentration at the periphery of the cell
What is hypochromia?
central pallor = bigger than 1/3
What is hyperchromia?
RBC saturated with Hb
What is Rouleaux formation?
RBCs become aligned in aggregates which resembles stacks of coins
What is autoagglutination?
RBCs may be present in aggregates varying in sizes
What are the ABO antibodies found in the serum of group O individuals?
anti-A and anti-B antibodies
What class of antibodies are in group O individuals?
IgG
What is a significant characteristic of IgG antibodies?
can readily cross the placenta
What are natural antibodies?
ones we produce due to exposure to antigens
What are the 2 ways to type blood?
direct and indirect
What is direct typing of blood?
detecting the antigen on the surface of RBC
What is indirect typing of blood?
(aka: reverse typing) | obtain the serum to detect antibody circulating in the patient
Is ABO genotype co-dominant, dominant/recessive, or incomplete dominant?
co-dominant
What is the nature of the ABO antigens on RBCs?
carbohydrates
What is the nature of the Rh antigens on RBCs?
proteins
Which (proteins or carbohydrates) are immunogenic? What does immunogenic mean?
protein | stimulates production of Abs
Why will a patient immediately die with mismatched ABO transfusion?
antibody against ABO is already circulating by the time of transfusion = immune system ready to attack and lyse foreign RBCs
Why won’t a patient die immediately with mismatched Rh factor blood transfusion?
no existing antibodies against Rh factor at the time of transfusion | 2-3 weeks until Abs against Rh factor are made
What do the ABO alleles encode for? What does the protein do?
transferases = enzyme that puts carbohydrate ABO antigen onto RBC
Do group O individuals have transferases? Why or why not?
no | only A and B antigens have transferases
How many subsets does the “A” allele have?
2 | A1 and A2
What are the only 2 times when we produce irregular antibodies?
pregnancy and blood transfusion
What are irregular antibodies?
antibodies that are not expected to be present in the blood | presence due to previous exposure to foreign antigen
Why do pregnant women produce irregular antibodies?
fetus is carrying dad’s ABO antigen = mom’s immune system is exposed to it = makes antibodies against it
How is the Rh-factor represented in blood typing?
by + or - = presence or absence of D-antigen
Which blood group antigens do normal flora carry?
only ABO, not Rh-hr
What are the 4 major allelic genes of the ABO antigens?
A1, A2, B, O
What are the natural antibodies group A individuals carry?
IgM anti-B Abs
What are the natural antibodies group B individuals carry?
IgM anti-A Abs
When do newborns begin to have natural antibodies? Why?
between 3-6 months post-birth | need to be exposed to foreign antigen
At what temp does IgG react best at? Does it cross the placenta?
37ºC (body temp) | crosses placenta
At what temp does IgM react best at? Does it cross the placenta?
21ºC (room temp) | can NOT cross placenta
Which mother’s blood type O, A, or B would be worse off for a fetus and why?
Type O mom = has both anti-A and anti-B IgG Abs that can readily cross the placenta
What is the only way to blood type a newborn if you could not detect both anti-A and anti-B antibodies?
Abs not yet detected because it takes time | can predict blood type based on parents’ blood type
If one detects IgM Abs, is this natural or irregular Ab?
irregular
What is another way besides blood transfusion and being pregnant that one can produce irregular antibodies?
organ transplants
What are the 3 loci of the Rh-hr blood group system?
C, D, E | co-dominant
Which Rh-hr detriment does not have an antibody against it?
d - does not have anti-d Abs
What are antithetical genes?
if one allele is not expressed (ie: C) then the one is likely expressed (ie: c)
What are the 2 major naming systems in use for rh-hr?
Fisher-Race | Weiner
How can you get rid of WBCs prior to transfusion?
irradiation = targets nucleus
