H&M chp 1

Question 1

Site of haemopoiesis for fetus 0-2 monthes

Answer 1

yolk sac

Question 2

Site of haemopoiesis for fetus 2-7 monthes

Answer 2

liver, spleen

Question 3

Site of haemopoiesis for fetus 5-9 monthes

Answer 3

bone marrow

Question 4

Site of haemopoiesis for infants

Answer 4

bone marrow of practically all bones

Question 5

Site of haemopoiesis for adults

Answer 5

vertebrae, ribs, sternum, skull, sacrum, pelvis, proximal ends of femur

Question 6

What is extramedullary haemopoiesis?

Answer 6

ability of liver and spleen to resume their fetal haemopoietic role

Question 7

What are haemangioblasts?

Answer 7

these stem cells are the common precursors to endothelial and haemopoietic cells. They are found in the AGM region and are believed to seed the liver and spleen.

Question 8

Where are haemopietic stem cells found?

Answer 8

bone marrow

Question 9

phenotype of haemopoietic stem cells?

Answer 9

CD34+ CD38-, neg for lineage markers, small lymphocyte

Question 10

CFU-GEMM

Answer 10

the earliest detectable mixed myeloid precursor which gibes rise to granulocytes, erythrocytes, monocytes, and megakaryocytes

Question 11

The bone marrow is composed of ____ and ____.

Answer 11

stromal cells, microvascular network

Question 12

The stromal cells include

Answer 12

adipocytes, fibroblasts, osteoblasts, endothelial cells, macrophages

Question 13

Function of stromal cells

Answer 13

secrete extracellular molecules including collagen, glycoproteins (fibronectin, thrombospondin), glycosaminoglycan (hyaluronic acid, chondroitin derivatives) to form the matrix. Secrete growth factors for stem cells.

Question 14

What stem cell is critical in stromal cell formation?

Answer 14

mesenchymal stem cell

Question 15

What do mesenchymal stem cells do?

Answer 15

with osteoblasts, they form niches, provide growth factors, adhesion molecules, and cytokines to support stem cells

Question 16

What process allows stem cells to traffic around the body? What cytokine is involved?

Answer 16

Mobilization, G-CSF

Question 17

What chemokine gradient is critical for homing?

Answer 17

SDF-1

Question 18

What interactions are critical for maintaining stem cell viability and production?

Answer 18

SCF and jagged proteins on stroma and their receptors KIT and NOTCH (respectively)

Question 19

What is SCF?

Answer 19

stem cell factor which is expressed on stromal cells. It binds to receptor KIT, which is a critical interaction for maintaining stem cell viability and production

Question 20

What are jagged proteins?

Answer 20

They are expressed on stromal cells and bind receptor NOTCH on stem cells. This interaction is crucial in stem cell viability and production

Question 21

What is SDF-1?

Answer 21

stromal-derived factor 1, its chemokine gradient is critical to stem cell homing

Question 22

What is self -renewal?

Answer 22

Haemopoiesis starts with stem cell division in which one cell replaces the stem cell and the other is commited to differentiation

Question 23

Why do early committed progenitors express low levels of transcription factors?

Answer 23

they may commit them to discrete cell lineages

Question 24

What are haemopoietic growth factors?

Answer 24

glycoprotein hormones that regulate proliferation and differentiation of haemopoietic progenitor cells and the function of mature blood cells

Question 25

____ are the major source of growth factors.

Answer 25

Stromal cells

Question 26

Where is erythropoietin made?

Answer 26

kidney

Question 27

Where is thrombopoietin made?

Answer 27

liver

Question 28

_____ and _____ have a negative effect on haemopoieses and may have a role in the development of aplastic anemia.

Answer 28

TNF and TGF-B

Question 29

Dimerization of a receptor leads to activation of a complex series of intracellular signal transduction pathways of which the 3 major ones are:

Answer 29

JAK/STAT, mitogen activated protein (MAP), and the phosphatidylinositol 3 (PI3) kinase pathways

Question 30

Transcription factors typically contain what 2 domains?

Answer 30

DNA binding and activation

Question 31

Haemopoetic tissue occupies about ___% of the marrow space in adults

Answer 31

50

Question 32

How common is the haemopoetic stem cell?

Answer 32

1 in every 20 million nucleated cells in bone marrow

Question 33

Are haemopoietic stem cells effectively transferred during transplant?

Answer 33

yes

Question 34

What are the functions of growth factors in the bone marrow?

Answer 34

stimulate proliferation of early bone marrow cells, direct differentiation, stimulate maturation, suppress apopotsis, affect function of non-dividing cells

Question 35

What cytokine has an important role in early haemopoiesis?

Answer 35

IL-3

Question 36

What is the function of TPO?

Answer 36

BFUemeg--> CFU meg

Question 37

What is the function of EPO?

Answer 37

BFUe--> CFUe

Question 38

What is the function of M-CSF?

Answer 38

CFUgm--> CFUm

Question 39

What is the function of G-CSF?

Answer 39

CFUgm--> CFUg

Question 40

What is the function of IL-5?

Answer 40

CFUeo--> eosinophil

Question 41

Granulocyte and monocyte formation can be stimulated by infection or inflammation through release of ___.

Answer 41

IL-1 and TNF

Question 42

____ phosphorylate downstream proteins targets and are regulated by cyclins.

Answer 42

Cdk

Question 43

___ are synthesized and degrarded in the cell cycle and regulate Cdk

Answer 43

cyclins

Question 44

Apoptosis results from the action of ____.

Answer 44

incracellular cysteine proteases called caspases which are activated following cleavage and lead to endonuclease digestion of DNA and disintegration of the cell skeleton

Question 45

FAS and TNF-R receptor have a _________ domain.

Answer 45

intracellular death

Question 46

What are DNA-binding domains?

Answer 46

leucine zipper or helix-loop-helix

Question 47

____ regulate migration of white cells

Answer 47

chemokines

Question 48

____ are involved in cell adhesion to ECM

Answer 48

integrins

Question 49

____ are involved in leukocyte and platelet adhesion to endothelium during inflammation and coagulation

Answer 49

selectin

Question 50

Does p53 have a role in the transduction pathway of growth factors?

Answer 50

NO- it has an important role in sensing DNA damage