Red Blood Cell Flashcards
(26 cards)
The rbc contains about …….. hemoglobin
270 million hemoglobin
The avg diameter of rbc in wet and dry specimens are ……….. and ………. respectively
7.4-7.8um dry
8.4 um wet
The SA/V of rbc is ……..
140u2 to 76-96 femtoliter (10^15)
The rbc count in males and females respectively
4.5 -6.5 ×10^12/L
3.8-5.8×10^12/L
At rbc thickest are the diameter is ……
And …….. at it it’s biconcavity
2.4um
1um
1 stem cell is capable of producing ……… no of red cells
8-16 red cells
The turnover of rbcs are ……….
10^11 -10^12 new red cells
Primitive erythropoiesis is first evident at what period in the yolk sac
Around the first 3 weeks
The transcription factors involved in rbc production include
GATA1 GATA2 FOG1 NFE2 TALI RUNXI
Distinguish the roles of GATA 1 and GATA 2 transcription factors in rbc maturation
GATA 2
Initiator of erythroid programme
Initial stage
Responsible for expansion and maintenance of progenitor cells
GATA 1
Terminal stage
Responsible for terminal differentiation and maturation of erythroid cells and megakaryocytes
List the order of erythropoiesis
CFU GEMM
early BFU E
Late BFU E
CFU EPronormoblast
Early normoblast
Intermediate normoblast
Late normoblast
Reticulocytes
Red blood cell
Other requirements for erythropoiesis include
Protein
Vitamins vitamins c dna and foliate metabolism vitamins E vit B6
Folic acid -DNA
Iron hemoglobin
Cobalt copper
HormonesTSH ACTH human growth hormone
Androgen stimulate erythropoietin
Oestrogen depresses erythropoiesis
Approximately…………. % of rbc are destroyed daily
2×10^11
The life span of is ………. and it travels ………. miles
100-120 days
175 miles
In order to maintain the shape of rbc membrane it requires ………. and ……..
Structural integrity
And continuous supply of energy for Na and K transport
The accepted arrangement of rbc arrangement was proposed by who in ……..
Nicolson and singer 1972
Discuss the distribution of lipids in the rbc membrane
Phospholipids 60%
Cholesterol 30
Glycolysis 10%
Phospholipids
Outer ucharged monolayer
Sphingomyelin 25%
Phosphatidylcholine 30%
Inner monolayer of charged
PE 28
PS 14
PI 3
Others PA charged
Lyso PA uncharged
Cholesterol dispersed amongst them
The rbc membrane contains approx ….. …… no of proteins
500 proteins
The major role of the rbc membrane protein are
Gives biconcavity to rbc membrane
Allows for deformation of the rbc
List the physiological variations that affect haematological indices
Occupation
Body build
Age
Sex
Ethnicity
Environment
Physiology conditions under which specimen was collected( supine position, diet etc)
The analytical variation that affect haematological indices include
Technique used for sample collection
Timing of the day
Storage and transportation of specimen
Variations in analytical method used e.g measurement of ESR using Winthrobe or westergreen method
How is an index parameter obtained
It is obtained by assessing a set of population presumed to be healthy.
Due to the fact that you cannot distinctively tell who is healthy normal value and range have been replaced by reference value and range
What is reactive significance of the index value
It indicates the physiological measurement in a healthy individual
It’s the basis of comparison for a physician to interpret result
How is a reference value obtained
It Is the interval in which 95 % of value of the reference population falls into I.e 2.5% of the time it is less than the upper limit and 2.5 % of the time it is greater than the upper limit
