Bone Marrow and Hematopoiesis

Question 1

Red Marrow

Answer 1

Active
Crammed with dividing stem cells and precursors of mature blood cells
Only in the heads of femur, humerus, sternum, ribs, cranium, pelvis, vertebrae

Question 2

Yellow marrow

Answer 2

Inactive bone marrow
Dominated by fat cells
May be reactivated (ex: extreme blood loss)

Question 3

2 methods to examine bone marrow

Answer 3

Bone marrow biopsy

Fine needle aspiration

Question 4

Bone marrow biopsy

Answer 4

Large bore needle
Whole section placed on slide
Visualization of architecture (bone and marrow)
General distribution of cells but not detail

Question 5

Fine needle aspiration

Answer 5

Spread on slide (marrow smear)
No sectioning/detail of architecture of bone
Visualization of cellular detail

Question 6

How much red:yellow marrow is there?

Answer 6

50:50

Question 7

3 lineages from a multipotential hematopoietic stem cell

Answer 7

Erythroid lineage
Myeloid lineage
Lymphoid lineage

Question 8

6 key cells in erythropoiesis

Answer 8

Proerythroblast
Basophilic erythroblast
Polychromatic erythroblast
Normoblasts
Reticulocytes
Mature RBCs

Question 9

2 key cells in granulopoiesis and how to differentiate

Answer 9

Myelocyte stage: nucleus occupies about half of cell

Meta-myelocyte: indented nucleus

Question 10

Megakaryocytes

Answer 10

Huge cells

Platelets are fragmented bits of their cytoplasm

Question 11

Monopoiesis

Answer 11

Develop from monoblasts

Monocytes circulate for a couple of hours before they enter CT, attach to endothelium, and become macrophages