3) RBC development

Question 1

erythron

Answer 1

total population of mature erythrocytes and their precursors in blood, bone marrow and other sites

Question 2

differentiations of erythropoiesis

Answer 2

CFU-GEMM + IL-3, GM-CSF →
CFU-EMk + IL-3, GM-CSF →
BFU-E + IL-3, GM-CSF →
CFU-E + EPO →
rubriblast

Question 3

at CFU-E stage, cells develop…

Answer 3

Rh antigens and EPO receptors

Question 4

Stephenson

Answer 4

discovered CFU-E

Question 5

Axelrad

Answer 5

discovered BFU-E

Question 6

in the bone marrow
difficult to ID morphologically

Answer 6

RBC precursors/progenitors

Question 7

insensitive to EPO

Answer 7

BFU-E

Question 8

changes that occur as erythrocytes develop

Answer 8

1. cell volume ↓
2. chromatin condenses
3. nucleoli disappear
4. RNA is lost (↓ blue)
5. hemoglobin is produced (↑ red)
6. mitochondria are lost
7. nucleus is ejected

Question 9

list both terminologies of morphologically identifiable RBCs, and how long they live (6)

Answer 9

1. Rubriblast —Pronormoblast (12 hours)
2. Prorubricyte —Basophilic normoblast (20 hours)
3. Rubricyte —Polychromatophilic normoblast (30 hours)
4. Metarubricyte —Orthochromatic normoblast (48 hours)
5. Reticulocyte (diffusely basophilic) —Polychromatophilic erythrocyte (2-3 days marrow, 1-2 days blood)
6. Mature RBC (120 days)

Question 10

final RBC stage with nucleus

Answer 10

metarubricyte/orthrochromatic normoblast

Question 11

final RBC stage capable of division

Answer 11

rubricyte/polychromatophilic normoblast

Question 12

—– RBCs are produced from a single rubriblast

Answer 12

16

Question 13

EPO is a ————

Answer 13

glycoprotein hormone

Question 14

erythropoiesis occurs over about —– days in response to EPO

Answer 14

5

Question 15

appearance of Fe-deficient cells

Answer 15

poorly hemoglobinized
scanty ragged cytoplasm
more basic stain (blue)

Question 16

megaloblastic development results from…

Answer 16

folate & B12 deficiency
required for DNA synthesis/nucleus development

Question 17

appearance of megaloblastic cells

Answer 17

large
increased amount of hemoglobin
asynchrony of nucleus/cytoplasm development

Question 18

examples of changes to cells in megaloblastic development in marrow and PB

Answer 18

Marrow
- increased cell size
- decreased NC ratio
- smooth nuclear chromatin
- asynchronous development

Peripheral smear
- hypersegmentation of WBCs
- karyorrhexis
- giant-band neutrophils
- macro-ovalocytes
- Howell Jolly bodies

Question 19

5 cells or more with 5 lobes or more

Answer 19

hypersegmentation
megaloblastic

Question 20

fragmented WBC nucleus

Answer 20

karyorrhexis

Question 21

inclusions of DNA pieces in RBCs

Answer 21

Howell Jolly bodies

Question 22

Answer 22

karyorrhexis

Question 23

Answer 23

Howell Jolly bodies

Question 24

Answer 24

giant band neutrophil

Question 25

Answer 25

hypersegmented neutrophil

Question 26

Answer 26

macro-ovalocyte