Blood

Question 1

Haemopoiesis is what?

Answer 1

blood development, occurs continuously.

Question 2

are platelets cells?

Answer 2

NO, takes 4-5 days to develop, lifespan of mature cells is 8-12 days

Question 3

for each of the following state duration of development and lifespan of mature cell:
erthryocyte
lymphocyte
neutrophil
esinophil
basophil
monocyte

Answer 3

RBC: 5-7 days, 120 days

lymphocyte: 1-2 days, months/years
neutrophil: 6-9 days, 6hrs to few days
esinophil: 6-9 days, 8-12 days
basophil: 3-7 days, ?
monocyte: 2-3 days, months/years

Question 4

which organs are hematopoietic?

Answer 4

mesoderm, liver and spleen, ossification of bone then marrow. cells are replaced continuously.

Question 5

what is a pluripotent stem cell? if it takes lymphoid path what happens? myeloid path?

Answer 5

can become any of the different blood cells.

lymphoid: can only become a lymphocyte
myeloid: can become any of other cells except lymphocyte.

Question 6

erythropoiesis is what?

Answer 6

RBC formation. we get a decrease in cell size throughout stages, loss of organelles, nucleus, cell division ceases, occurs in red bone marrow.

Question 7

where is red bone marrow located?

Answer 7

skull, clavicle, ribs, sternum, ends long bones.

Question 8

what is the smallest cell in your body?

Answer 8

RBC 7um

Question 9

erythropoiesis takes how long? what stage is when cell division completely stops? when do we have complete loss of nucleus?

Answer 9

1 week
intermediate normablast.
reticulocyte (ribosomes still occur, they are lost in erythrocyte mature stage, when ribos are lost cell becomes esinophillic).

Question 10

genesis of leukocytes occurs in which two lineages?

Answer 10

1. myelocytic: granulocytes and monocytes, occurs in bone marrow
2. lymphocytic: lymphocytes, once they leaves bone marrow they go to lymph glands, spleen and thymus where they mature.

Question 11

what are the precursors in haemopoiesis? after this they become?

Answer 11

unipotent stem cells
“blasts”: once cells become this form, they have features morphologically similar to that of a mature cell (therefore start committing)

Question 12

what is CFU? what does it mean?

Answer 12

colony forming units, once cells become this they are committed to a particular cell line.

Question 13

what are the general names of each stage after a blast?

Answer 13

"cell" promyelocyte
"cell" myelocyte
"cell" metamyelocyte
"cell" stab cell
mature form of "cell"
(every cell goes through these with cell name in front, as they mature cell size decreases and increase in granules)

Question 14

what is diapedesis?

Answer 14

movement of blood cells from colony into sinuses/capillaries (fenestrated)

Question 15

how are platelets formed?

Answer 15

formed by large multinucleate cells= megakaryocytes (they bud off from these and go to capillaries). they contain four types of granules.

Question 16

once cells are at “blast” stage are they committed?

Answer 16

YES.

Question 17

lymphopoiesis is what?

Answer 17

progressive decrease in cell size, occurs in marrow and in immune tissues.

Question 18

anemias are disorders of what cell type? common symptoms?

Answer 18

RBC

reduced RBCs, low hematocrit, low Hb, iron deficiency is most common cause, lack O2 bc Hb carrying capacity is altered.

Question 19

what is megoblastic anemia?

Answer 19

abnormal large precursor megaloblasts, usually due to vit B12 deficiency which is needed for normal maturation of RBCs.