Exam 3: Hematopoiesis

Question 1

Describe Hematopoietic Stem Cells:

Answer 1

• Pluripotential
• Self-renew
• Produce two precursor cellls
  
  • myeloid stem cells
  • lymphoid stem cells
• can only identify by cell surface markers

Question 2

Leukocytes can be divided further give the two major divisions:

Answer 2

1. Granulocytes
2. Agranulocytes

Question 3

Ganulocytes, a form of Leukocyte, has three additonal linages, name them.

Answer 3

• Neutrophils
• basophils
• eosinophils

Question 4

Agranulocytes, a form of leukocytes has two additional linages, what are they?

Answer 4

• Monocytes
• Lymphocytes

Question 5

Myeloid stem cells, derived from hematopoietic stem cells can give rise to 5 CFU, what are they?

Answer 5

• Erthrooid
• Megakaryocyte
• Basophil
• Eosinophil
• Granulolcyte-Macrophage

Question 6

What two cell lines can arise from lymphoid stem cells?

Answer 6

• T-cell progenitor
  
  • matures in thymus
• B-cell progenitor
  
  • matures in bone marrow

Question 7

A GM-CFU can give rise to two different linages, explain the steps to get to a macrophage. 4 Steps:

Answer 7

1. Monoblast
2. promonocyte
3. monocyte
4. macrophage

Question 8

A GM-CFU can give rise to two different linages, explain the steps to get to a Neutrophil. 6 Steps

Answer 8

1. Myeloblast
2. Promyelocyte
3. meylocyte
4. Metamyelocyte
5. band cell
6. Neutrophil

Question 9

An Eosininophil/basophil-CFU can give linages, explain the steps to get to a Eosiniphil or Basophil. 6 steps

Answer 9

1. Myeloblast
2. Promyelocyte
3. Myelocyte
4. metamyelocyte
5. band cell
6. eosinophil or basophil (becomes mast cell)

Question 10

A megakaryocyte CFU will give rise to a platelet, what 3 steps are involved?

Answer 10

1. Megakaryoblast
2. megakaryocyte
3. platelets

Question 11

The Erythoroid CFU will eventually give rise to RBCs, what steps are required to get there? 6 steps

Answer 11

1. Proerythroblast
2. Basophilic erythroblast
3. polychromatophilic erythroblast
4. orthochromatic erythroblast
5. Reticulocyte
6. Erythrocyte (RBC)

Question 12

Explain Erythropoietin and the JAK-STAT Pathway

Answer 12

1. EPO produced in renal cortex transported to bone marrow by blood circulation
2. In bone marrow EPO binds to dimerized EPO receptor and induces bind of STAT5 protein to JAK2
3. STAT5 becomes activated (phophorylated) and homodimerizes.
4. the phosphorylated STAT5 homodimer translocates into the nucleus
5. binds to DNA and activates transcription of specific genes required for erythopoiesis.