1. Hematopoiesis

Question 1

where does hematopoiesis begin?

Answer 1

In the umbilical vesicle of the fetus during the 1st trimester

Question 2

what do hematopoietic islands develop from?

Answer 2

Hemangioblasts

Question 3

What are hemangioblasts?

Answer 3

progenitors of hematopoietic and endothelial cells

Question 4

Where does hematopoiesis occur in the 2nd trimester?

Answer 4

The liver and then the spleen

Question 5

When does bone marrow become the primary site of hematopoiesis?

Answer 5

during the 7th month of pregnancy

Question 6

sinusoids

Answer 6

Vascular units present in bone marrow w/ endothelial lining, a discontinuous basement membrane, and adventitial cells

Question 7

adventitial cells

Answer 7

a support cell that produces reticular fibers and secrete cytokine (CSFs, IL-5, and IL-7)

Question 8

how do blood cells travel the bone marrow-sinusoidal system?

Answer 8

first it will push against the endothelial cell before fusing w/ it and piercing the luminal PM. this forms a transitory opening that each blood cell will squeeze through to enter the sinusoidal membrane. the cell then repairs itself and the opening disappears

Question 9

what blood cells will develop near the sinusoidal wall and which develop further away?

Answer 9

Erythrocytes and megakaryocytes develop near the wall while granulocytes will develop further from the sinusoidal wall

Question 10

Red bone marrow

Answer 10

immature, more hematopoietic cell and less adipose, present in long bones and spongy bone, specific cells develop in clusters

Question 11

Yellow bone marrow

Answer 11

mature, mostly adipose except in vertebrae, ribs, pelvis, and shoulder girdle. Still has hematopoietic potential

Question 12

Calculating normal cellularity

Answer 12

Subtract individuals age from 100 and add +/- 10%

i.e. 100-22=88+/-10% so 22 would be 78-98%

Question 13

hypocellular marrow

Answer 13

small number of blood forming cells are found

due to aplastic anemia or chemotherapy

Question 14

hypercellular marrow

Answer 14

bone marrow affected by hematopoietic cell tumors

Question 15

bone marrow aspirate

Answer 15

need will be inserted through skin into bone. typically as posterior part of iliac crest. Then spread as a smear to be examined

Question 16

Bone marrow core biopsy

Answer 16

biposy needle is inserted into bone to get an intact bone marrow sample

Question 17

what progenitors do HSC give rise to?

Answer 17

common myeloid progenitor and common lymphoid progenitor

Question 18

What progenitors do CMP give rise to?

Answer 18

Megakaryocyte/erythrocyte progenitor and granulocyte/monocyte precursors

Question 19

what progenitors do MEP give rise to?

Answer 19

Megakaryocyte-committed progenitor cells (MEP) or erythrocyte committed progenitor cells (ErP)

Question 20

What progenitors do GMP give rise to?

Answer 20

Neutrophil progenitors, eosinophil progenitors, basophil progenitors, and monocyte progenitors