Erythrocyte Stages - Features

Question 1

Rubriblast (Pronormoblast) - Size

Answer 1

12-19 mcm

Question 2

Rubriblast (Pronormoblast) - N:C Ratio

Answer 2

8:1

Question 3

Rubriblast (Pronormoblast) - Nucleus

Answer 3

• Contains 0/1 or 2 nucleoli
• Large, round nucleus
• Chromatin is purple red and has fine pattern (only seen in rubriblast)

Question 4

Rubriblast (Pronormoblast) - Cytoplasm

Answer 4

Deep blue (due to ribosomes-RNA activity) without granules

Question 5

Rubriblast (Pronormoblast) - Features

Answer 5

• Earliest recognizable stage
• High RNA activity (needed for production of CHONs required for Hgb synthesis)
• Globin production begins

Question 6

Prorubricyte (Basophilic Normoblast) - Size

Answer 6

12-17 mcm

Question 7

Prorubricyte (Basophilic Normoblast) - NC Ratio

Answer 7

6:1

Question 8

Prorubricyte (Basophilic Normoblast) - Nucleus

Answer 8

• Nucleoli may be present in the early stage but disappears later
• Nuclear chromatin is deep purple red and begins to condense

Question 9

Prorubricyte (Basophilic Normoblast) - Cytoplasm

Answer 9

Deeper, richer blue

Question 10

Prorubricyte (Basophilic Normoblast) - Features

Answer 10

• Most helpful criteria (when comparing with rubriblast: COARSER CHROMATIN and ABSENCE OF NUCLEOLI
• Start of Hemoglobin Synthesis (Hgb pigmentation not yet evident)

Question 11

Rubricyte (Polychromatophilic Normoblast) - Size

Answer 11

11-15 mcm

Question 12

Rubricyte (Polychromatophilic Normoblast) - NC ratio

Answer 12

4:1

Question 13

Rubricyte (Polychromatophilic Normoblast) - Nucleus

Answer 13

• Increased clumping of the chromatin
• No nucleoli are present

Question 14

Rubricyte (Polychromatophilic Normoblast) - Cytoplasm

Answer 14

Pink (Hgb) + blue = Murky gray-blue (only seen in Rubricyte)

Question 15

Rubricyte (Polychromatophilic Normoblast) - Features

Answer 15

• Hemoglobin synthesis increases (Hgb pigmentation becomes evident)
• Last stage capable of mitosis
• Polychromatophilic - many color
• Progressive decreased in DNA synthesis

Question 16

Metarubricyte (Orthochromic normoblast or nucleated RBC/NRBC) - Size

Answer 16

8-12 mcm

Question 17

Metarubricyte (Orthochromic normoblast or nucleated RBC/NRBC) - NC ratio

Answer 17

1:2

Question 18

Metarubricyte (Orthochromic normoblast or nucleated RBC/NRBC) - Nucleus

Answer 18

Chromatin pattern is tightly/completely condensed = Pyknotic nucleus

Question 19

Metarubricyte (Orthochromic normoblast or nucleated RBC/NRBC) - Cytoplasm

Answer 19

Reddish pink

Question 20

Metarubricyte (Orthochromic normoblast or nucleated RBC/NRBC) - Features

Answer 20

• Last nucleated stage
• Hgb synthesis continues
• Loss of vimentin
• Nucleus expulsion or extrusion occurs (later at this stage)
• Pyrenocyte (pyknotic/enveloped extruded nucleus) - engulfed by BM macrophages

Question 21

a protein which hold organelles in proper location in the cytoplasm

Answer 21

vimentin

Question 22

Reticulocyte (Polychromatophilic erythrocyte) - Size

Answer 22

7-10 mcm

Question 23

Reticulocyte (Polychromatophilic erythrocyte) - Nucleus

Answer 23

Cell is anuclear

Question 24

Reticulocyte (Polychromatophilic erythrocyte) - Cytoplasm

Answer 24

Various degrees of polychromasia (mixed pink and blue staining)

Diffuse reticulum

Question 25

Reticulocyte (Polychromatophilic erythrocyte) - Features

Answer 25

- End stage of Hgb synthesis - Diffusely basophilic erythrocyte (Wright stain) - Reticulocyte (Supravital stain - Endoribonuclease digests the ribosomes - Resides in the BM for 1-2/2-3 days prior to its release in the PB - Stays in the PB for about 1 day before becoming mature RBC

Question 26

Erythrocyte - size

Answer 26

6-8 mcm

Question 27

Erythrocyte - Nucleus

Answer 27

Anuclear

Question 28

Erythrocyte - Cytoplasm

Answer 28

Salmon-pink with central pale area

Question 29

Erythrocyte - Features

Answer 29

- Erythrocytes cannot divide - No mitochondria - Biconcave disc (Discocyte) - Hemoglobin is the cell's main component

Question 30

- preparation for Hgb synthesis - start of globin production

Answer 30

Rubriblast (Pronormoblast)

Question 31

2 portions of hemoglobin

Answer 31

1. Heme 2. Globin - protein protion

Question 32

WHY “DEEPER, RICHER BLUE” Cytoplasm in Prorubricyte?

Answer 32

There’s a continuous increase in the amount of ribosomal RNA and ribosomes

Question 33

Progressive decreased in DNA synthesis is caused by?

Answer 33

Clumping of the chromatin

Question 33

REASONS WHY HGB PIGMENTATION IS NOT YET EVIDENT AT Prorubricyte Stage:

Answer 33

1. Only a minute amount of Hgb is produced 2. The minute amount of Hgb produced is being masked by ribosomes and rRNAs

Question 34

“raspberry appearance” * Increasing Hgb amount * Residues (e.g. ribosomes, rRNA) from the previous stage are used to continue Hgb synthesis despite the nucleus is inactive.

Answer 34

Metarubricyte

Question 35

EXPULSION OF THE NUCLEUS

Answer 35

Metarubricyte

Question 36

Expressed on the surface of pyrenocyte Serves as a signal for bone marrow macrophages to engulf/eat the pyrenocyte

Answer 36

Phospatidylserine

Question 37

Nuclear remnants RBC inclusions

Answer 37

Howell-Jolly Bodies

Question 38

Dfifusely basophilic stage

Answer 38

Reticulocyte

Question 39

- Blue appears in dots that are scattered throughout cytoplasm - Also known as basophilic stippling

Answer 39

Punctate basophilia

Question 40

- polychromatic erythrocyte - bluish cytoplasm appears to have very fine pattern

Answer 40

Diffused Basophilia

Question 41

➔ basophilic stippling ➔ bluish cytoplasm appears clustered/dotted

Answer 41

Punctate Basophilia

Question 42

- Example: new methylene blue - Stains residual rRNA that appears as small blue strands – called the “reticulum”

Answer 42

Supravital Stain

Question 43

➔ time it takes for the cells to be in that particular stage before they develop into the next stage

Answer 43

Transit time