Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Hematology Exam I > Hematopoiesis > Flashcards

Hematopoiesis Flashcards

1
Q

Where does hematopoiesis take place?

A

Bone Marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the cell lifespan of: Lymphycytes, RBCs, Platelets, Granulocytes?

A

Lymphocytes: years

RBCs: 120 days

Platelets: 7-10 days

Granulocytes: 6-8 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are some important characteristics of Hematopoietic Stem Cells?

A
  • Make up a very small amount of bone marrow cells (0.1 - 0.01%)
  • Give rise to progenitor cells of all lineages
  • Cannot be identified morphologically
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the role of Bone Marrow Stromal Cells?

A

Maintenance and Differentiation of hematopoietic cells via CONTACT throughout the differentiation process

(Bind less and less as the cells mature)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the function of Cytokines in Hematopoiesis? (Progenitor Cell Cytokines vs. End-Stage Cytokines)

A

Cytokines drive specific cell differentiation pathways

Progenitor Cell Cytokines: (e.g. Stem Cell factor) act on immature cells

End-Stage Cytokines: act on more differentiated cell types to induce lineage specific differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is G-CSF and what is it’s function?

What type of cell releases G-CSF and where?

A

G-CSF (Granulocyte Colony Stimulating Facor) is a cytokine that calls the bone marrow to produce granulocytes (e.g. Neutrophils, eosinophils, and basophils), which then traffic to the site of inflammation and phacoytize bacteria

Released by macrophages at inflammatory sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is EPO, where is it produced, why is it produced, and what does it do?

What inhibits EPO?

A

EPO (Erythropoietin) is a cytokine produced by the peritublar interstitial cells (Kidney) in response to hypoxia.

EPO tells the bone marrow to increase production and release of RBCs

EPO is inhibited by Increased Oxygen Pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is TGF-B and what does it do?

A

TGF-B is a cytokine that DOWNREGULATES stem cell growth/differention by decreaseing cell surface receptors for growth/differentiation of cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is G-CSF used for clinically? (2 things)

A
  1. Stimulates the bone marrow to release stem cells into the blood, which can then be harvested using a Flow Cytometer (Cell Sorter)

***Much less invasive, lower chance of infection than sticking a needle into their bone marrow***

  1. Stimulates granulopoiesis (especially Neutrophils) following c__hemotehrapy/bone marrow cell production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the clinical utility of GM-CSF? (Granulocyte Monocyte Colony Stimulating Factor)

A

***Stimulates both granulocytes and monocytes (eventually become macrophages)***

  1. Increases myeloid cell recovery in bone marrow transplant patients
  2. MORE TOXIC than G-CSF (e.g. Thrombosis and Capillary Leak Syndrome) so usually not given (G-CSF given instead)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the clinical utility of EPO?

A
  1. Used to treat anemia as a result of renal insufficiency

***Increases RBC mass***

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the two forms of Bone Marrow and Where are they found?

A

Yellow Marrow: normally inactive and mainly found in adipose tissue

Red Marrow: active in hematopoiesis

  • First few years of live –> all marrow is Red
  • By age 18, red marrow is found in the ribs, sternum, and pelvis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where does extramedullary hematopoiesis take place?

A

Spleen and liver when bone marrow is dysfunctional/unable to meet demands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the four things to be aware of concerning Erythropoiesis?

A
  1. Cell Size decreases
  2. Nuclear:Cytoplasm ratio decreases
  3. Nucleoli decrease in number, eventually disappear
  4. Cytoplasm goes from darker blue to lighter blue due to decreased RNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens when the RBC matures from a Metarubricyte to a Reticulocyte?

A

It loses its nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When does Erythropoiesis start, continue, and predominate?

A

Starts: Primitive RBCs in the embryonic yolk sac

Continues: extramedullary organs (i.e. Liver and Spleen)

Predominates: in the red marrow during late fetal development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a Reticulocyte?

A

The stage of RBC maturation just before an Erythrocyte

18
Q

What will lead to an increased Reticulocyte count?

A

Will increase as erythropoiesis is highly active (Bone marrow is trying to push them out as fast as possible)

19
Q

What cells are produced during Granulopoiesis?

A

Neutrophils, Eosinophils, and Basophils

20
Q

What is a Band Cell and when will you see it? Percentages (normal vs. infection)

A

A slightly immature granulocyte (e.g. Neutrophil - will have a horseshoe nucleus compared to regular neutrophil) that will appear in the blood when the bone marrow is trying to push out cells as fast as possible

Normal: 3-5%

Bacterial Infection: 20-25%

21
Q

What is a Left Shift or Shift to the Left?

A

Used to describe increased percentage of Band Cells in the blood

22
Q

Where are neutrophils normally located (Two Pools) in the blood stream?

A

50% are traveling in the blood stream (in Motion)

50% are loosely attached to the vascular endothelial cells (Stationary)

***This is a DYNAMIC process***

23
Q

What are Monocytes and Where are they produced?

A

Monocytes are baby Macrophages that are produced in the bone marrow

24
Q

What are Macrophages called in: Loose Connective Tissue, Liver, Osteoclasts, and Nervous System?

A

Loose Connective Tissue –> Histiocytes

Liver –> Kupffer Cells

Bone –> Osteoclasts

Nervous System –> Microglial Cells

25
Q

How long do Monocytes last? Macrophages?

A

Monocytes circulate for ~8 hours then enter tissues and differentiate into macrophages

Macrophages live months to years

26
Q

What kind of cells does Lymphopoiesis produce?

A

T lymphocytes, B lymphocytes, and Natural Killer (NK) cells

27
Q

What is unique about NK cells? (***Boards***)

A

They are not part of adaptive or acquired immunity; they are part of innate immunity

28
Q

What cells mature entirely in the bone marrow?

A

B lymphocytes and NK Cells

29
Q

At what stage do you get of self-reactive B cells?

A

The immature B cell stage

(Express only IgM, rather than a mature, which expresses IgM and IgD)

30
Q

What do activated B cells give rise to?

A

Plasma and Memory Cells

31
Q

Maturation process of T lymphocytes

A

Leave the bone marrow as prothymocytes (prolymphocyte)

Arrive at Thymus, where they mature/differentiate into T lymphocyte subsets

***If they’re lucky (95-98% of prothymocytes die in the thymus because they’re self-reactive or they recognize someeone else’s MHC)

From there, they go out and populate lymphoid organs

32
Q

What are platelets?

A

Anuclear cytoplasmis remnants of megakaryocytes

Play a role in hemostasis

33
Q

What is endomitosis and what stimulates this process?

A

Endomitosis is the process by which Megakaryocytes undergo cytoplasmis divisions without cell division; can become a large polyploid (32N) cell

Thrombopoietin is a cytokine that stimulates endomitosis and production of thrombocytes (aka platelets)

34
Q

How do Megakaryocytes produce platelets?

A

They form long cytoplasmic extension which constrict at various points and divide into fragments

(100-1000 platelets per Megakaryocyte)

35
Q

Platlets

  1. Lifespan
  2. Where are they phagocytized when they die?
  3. Emergency reserve of platelets is located…
A
  1. Lifespan: 9 days
  2. Death: Liver or Spleen
  3. Emergency Reserve: Spleen
36
Q

What is an Absolute Cell Count?

A

It provides the Quantity of each cell type per unit volume

37
Q

What is the Differential Count?

A

It is a Relative Count** and therefore gives the **PERCENTAGE (%) of each cell type

38
Q

Can you look at Absolute Cell Count or Differential Count and conclude that a patient is normal?

A

No; you have to look at both

39
Q

What type of cell accounts for the highest percentage of Bone Marrow cells?

A

Granulocytes

(Stem cells is the lowest)

(RBCs is the second highest, as they have a longer lifespan than granulocytes)

40
Q

Who has higher RBC count between males and females?

A

Males (4.3 - 5.7)

vs.

Females (3.8 - 5.1)

41
Q

What is a normal Reticulocyte count?

A

About 1% of your RBCs (0.5 - 1.5%)

Hematology Exam I (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions