Erythrocytic developmental series

Question 1

What are the key characteristics of a rubriblast (pronormoblast)?

Answer 1

• 14 to 24 um
• N:C 8 to 1
• 1 to 2 nucleoli
• Fine chromatin
• Royal blue cytoplasm

Question 2

What are the key characteristics of a prorubricyte (Basophilic normoblast)?

Answer 2

• 12 to 17 um
• N:C 6 to 1
• coarser chromatin with parachromatin
• nucleoli not usually visible

Question 3

What are the key characteristics of a rubricyte (polychromatophilic normoblast)?

Answer 3

• 10 to 15 um
• N:C 4 to 1
• Polychromatophilic cytoplasm due to hemoglobin production
• clumped chromatin with parachromatin

Question 4

What are the key characteristics of a metarubricyte (orthochromic normoblast)?

Answer 4

• 8 to 12 um
• N:C ratio 1 to 2
• Nucleus is pyknotic

Question 5

What are the key characteristics of a reticulocyte ( polychromatophilic erythrocyte)?

Answer 5

• 7 to 10 um
• no nucleus
• diffusely basophilic cytoplasm
• reticulum seen with supravital stain

Question 6

What are the key characteristics of a mature erythrocyte?

Answer 6

• 7 to 8 um
• biconcave disk
• reddish-pink cytoplasm with an area of central pallor