blood and bone marrow

Question 1

Give relative percentages

Neutrophils	
Lymphocytes 
Monocytes 
Eosinophils	
Basophils

Answer 1

Neutrophils	(60-70%)
Lymphocytes (20-25%)
Monocytes (3-8%)
Eosinophils	(2-4%)
Basophils	(0.5-1%)

Question 2

Q2: Describe the types of granules and their various functions.

Answer 2

Granule Function
Azurophilic (non-specific)
Primary
Myeloperoxidase, a lysosomal hydrolase, digests foreign
material after fusion to bacteria
Neutrophilic (Specific to
Neutrophils) Secondary
plus Tertiary granules
Specialized LROs (lysosome-related organelles) containing
enzymes (e.g. type IV collagenase) to facilitate neutrophil
migration, complement activators, and antimicrobial
molecules. Tertiary granules are also believed to help
neutrophils move through tissue (phosphatases and
metalloproteinases)
Eosinophilic (Specific to
Eosinophils) Secondary
Contains cytotoxic compounds against protozoans and
helminthic parasites and neurotoxins against parasites.
4 specific proteins: Major Basic Protein, other 3 are antiparasitic
plus histaminase and arylsulfatase which
neutralize “first responder” leukotrienes
Basophilic (Specific to
Basophils) Secondary
Contains heparin

Question 3

Q3: What features allow you to differentiate between the erythrocyte lineage and the granulocyte lineage?

Answer 3

A: Shape and size of nucleus, density of organelles in cytoplasm judged as “quality” of cytoplasm. Appearance of specific granules.

Question 4

Q4: What are the characteristics of the nuclei and cytoplasm of a basophilic normoblast?

Answer 4

A: Basophilic erythroblasts have very basophilic cytoplasm and large round nuclei characterized by open “spaces” in the chromatin indicating a relatively active nucleus. This cell can divide.

Question 5

Q5: What stains basophilic in the cytoplasm?

Answer 5

A: Ribosomes synthesizing hemoglobin and transferrin.

Question 6

6. Identify polychromatophilic erythroblasts (polychromatic normoblast).

Q6: What is their size compared to basophilic erythroblasts?

Answer 6

A: These cells are smaller than the basophilic erythroblasts.

Question 7

: Why is their cytoplasm polychromatophilic and what are the characteristics of the nucleus?

Answer 7

A: They get their name from the fact that hemoglobin synthesis adds acidophila to the cytoplasm, giving it a mixture of basophilia and acidophilia, hence the name polychromatophilic. Their nuclei are still round, but smaller with more clumped chromatin indicating a somewhat less active nucleus than that of the basophilic erythroblast. This cell can divide.

Question 8

7. Identify normoblasts (orthochromatophilic erythroblast).

Q8: What is the relative size, color of the cytoplasm, color and pattern of nucleus?

Answer 8

A: These cells are nearly as small as mature RBCs. The color of their cytoplasm should be nearly the color of a mature RBC, hence the name orthochromatophilic. The nuclei of these cells are dark indicating a very clumped chromatin and may be described as pyknotic. This nuclear appearance is indicative of impending nuclear extrusion. This cell cannot divide.

Question 9

2. Identify promyelocytes.

Q9: What is the relative size, color of the cytoplasm, and characteristics (shape & chromatin quality) of nucleus?

Answer 9

A: Cell diameter is up to four times of a mature red blood cell. It has a basophilic cytoplasm with prominent, dark azurophilic (non-specific) granules. The nucleus contains both euchromatic and heterochromatic regions, it is round or oval and eccentric.

Question 10

3. Identify neutrophilic myelocytes.
   Q11: What is the relative size, color of the cytoplasm, and characteristics (shape & chromatin quality) of nucleus?

Q12: Does this cell contain specific granules? Can it divide?

Answer 10

A: This cell is smaller than a promyelocte, about two red cells in diameter. It has a pale blue cytoplasm and first appearance of specific, neutrophilic granules. The nucleus is more condensed and becomes flattened on one side.

A: Yes, first appearance of specific granules. This cell can divide

Question 11

4. Identify neutrophilic metamyelocytes.
   Q13: What is the relative size, color of the cytoplasm, and characteristics (shape & chromatin quality) of nucleus?

Q14: Does this cell contain specific granules? Can it divide?

Answer 11

A: This cell is a bit smaller (10-12 μm) than a myelocyte, the cytoplasm is a bit paler and the nucleus is clearly indented (kidney-shaped).

A: It has more specific granules than a myelocyte. This cell cannot divide.

Question 12

5. Identify band neutrophils (stab cells).
   Q15: What is the relative size, color of the cytoplasm, and characteristics (shape & chromatin quality) of nucleus?

Q16: Does this cell contain specific granules? Can it divide?

Answer 12

A: This cell has a diameter equal to one and one-half or two RBCs. The cytoplasm is just a bit bluer than a mature neutrophil. The nucleus is condensed and horseshoe or U-shaped. For the purposes of this course, we will set as a criterion of identification that the thickness of the arms of the U-shaped nucleus is approximately equal.

A: It has more specific granules than a metamyelocyte. This cell cannot divide.

Question 13

Q17: What is their relative size and what is derived from the megakaryocyte?

Answer 13

A: Unusually large, up to 100 μm in diameter, cells produce platelets.

Question 14

Q18: Summarize the morphological changes of the cytoplasm and nucleus during granulocyte development

Answer 14

.

1. The cytoplasm will show a shift from non-specific to specific granules as promyelocytes develop into mature granulocytes.
2. The cytoplasm of a promyelocyte is bluish, but not nearly as blue as the early stage (basophilic erythroblast) in the red series.
3. Promyelocyte cytoplasm contains azurophilic granules, which are lysosomes, but not specific (neutrophilic, eosinophilic, or basophilic) granules.
4. The number of azurophilic granules is diluted out by cell divisions and the cytoplasm becomes successively paler blue.
5. Specific granules develop later, as the first sign of cytoplasmic differentiation (myelocytes). The specific granules continue to accumulate as the cells mature.
6. The nucleus decreases in size in parallel with decrease in cell size.
7. Nuclear chromatin undergoes successive condensation of chromatin.
8. Shape of the nucleus undergoes successive flattening, indentation, and lobulation, resembling the deflation of a balloon.