Brainscape's Knowledge GenomeTM

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


See full index

Cardiopulmonary Renal > Hematopoiesis > Flashcards

Hematopoiesis Flashcards

1
Q

What is Hemopoiesis?

A

The process through which formed elements of the blood are produced is called hematopoiesis

Some books refer to as Heimopoiesis

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

What are formed elements? What is the function?

A

Vital role in normal functioning of human being

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

What are totipotent cells? Where is it found?

A

Ability to develop into all tissu3s

Embryonic
-endoderm, mesoderm, ectoderm

Extra-embryonic
-placental, amnion, chorion

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

What does pluripotent mean?

A

Ability of the body to develop into all cells & tissues of the body
— 210 differentiated adult cell types

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

What is multipotent ?

A

Ability to develop into a small number of different cell types

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

What is unipotent?

A

Ability to develop into a single cell type

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

What are hematopoietic stem cells(HSC)?

A

Gives rise to multiple colonies of progenitor stem cells

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

What are the types of progenitor cells(PC)?

A
  • common myeloid progenitor cells. (CMP) cells)
  • common lymphoid progenitor cells (CLP) cells

Previously called colony forming 7nits

CMP differentiates into single cell line- restricted progenitors
-(CFU-GEMM) —> granulocytes, erythrocytes, monocytes, megakaryocytes

  • CLP differentiated into T cells, B cells and NK cells
  • Precursor cells- morphologically distinct, no self renewal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Summarize hematopoiesis

A

Erythrocytes & leukocytes are formed in several organs before differentiation of the bone marrow
-yolk sac phase- hematopoiesis begins the 3rd week of gestation- formation of “blood islands” (3-8 weeks)

  • hepatic phase- major blood forming organ in second trimester
  • bone marrow phase- begins during second trimester as well (also involves other lymphatic tissues)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where does hemopoiesid occur after birth?

A

Only in the bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are HSCs?

A

HSCs reside in the cavit of long & axial bones, surrounded by stroke.

Stroma: made of cells derived from mesenchymal stem cells- give rise to

  • fibroblasts
  • adipocytes
  • endothelial cells
  • Osteoblasts

Stroma is necessary to suort the hematopoietic stem cells

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

What is a stem cell niche?

A

A spatial structure (micro environment) in which HSCs are housed and maintained by allowing self renewal in the absence of differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the functions of stem cell line?

A
  • storage of quiescent stem cells
  • self Renewal
  • inhibition of differentiation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where is stem cell (endosteal) niche found?

A

Anatoical location: Epiphyseal areas (spongy bone or “cancellous bone”)

Stem cells are closely associated with the osteoblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the significance of a vascular niche?

A
  • Quiescent HSCs detach from the endosteal niche and migrate towards the center of the bone marrow to the vascular zone from where they establish hematopoiesis
  • Thus specific site where endothelial cells, fibroblasts and adipocytes are found is called the vascular niche, as opposed to endosteal niche
  • Collectively, these two niches strongly cooperate to balance HSC quiescence, self-renewing activity, as well as production of early progenitors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Contrast endosteal and vascular niches

A

Vascular niches: site of proliferation of the multi potent progenitors

Endosteal niche: HSC in contact with osteoblasts lining with endosteum. Osteoblasts regulate the number and the fate of the HSC at the specific niche

17
Q

What are the functions of vascular niches?

A
  • Support and promote the differentiation & maturation of progenitors into formed elements
  • Secretion of growth factors by stromal cells
18
Q

Describe bone marrow structure

A
  1. Structure: reticular fibers, veins, arteries, sinusoids (type of capillaries), islands of cells
  2. Red marrow: active hematopoiesis
  3. Yellow marrow: fat, capillaries, retifular cells, inactive hematopoiesis
19
Q

What do growth factors regulate?

A

Regulate proliferation & maturation

Progenitor cells have surface receptors for specific cytokines and growth factors (glycoproteins)

Hematopoietic cells will die unless exposed to growth factors

20
Q

What are erythropoietins(EPO)?

A

Produced by kidneys increase erythrocyte precursors

21
Q

What are thrombopoietin (TPO)?

A

Hormone from liver stimulates thrombocytes formation

22
Q

What are cytokines?

A

Local hormones of bone marrow

  • produced by some marrow cells to stimulate proliferation in other marrow cells
  • colony stimulating factor (CSF) & interleukin stimulate leukocyte production
23
Q

What is myelopoiesis?

A

Erythropoiesis
-formation of erythrocytes

Granulocytopouesis
-formation of granulocytes

Monocytopoiesis
-formation of monocytes

Thrombopoiiesis
-formation of thrombocytes(platelets)

24
Q

What is lymphopoiesis?

A

Formation of lymphocytes

25
Q

What simulates erythropoiesis ?

A

Erythrocyte formation, called erythropoiesis, occurs in adult red bone marrow of certain bones

The main stimulates fir erythropoiesis is hypoxia

Erythropoietin- produced by kidney

26
Q

Explain erythropoiesis

A
  1. Proerythroblast 14- 19 um, no hemoglobin, large nucleus, basophilic cytoplasm
  2. Basophilic (early) erythroblast: 12- 17 um, some hemoglobin, condensing nucleus
  3. Polychromatophilic erythroblast: 12-15 um, “muddy” cytoplasm
  4. Orthochromatophilic (late) erythroblast(normalblast): 8-12 um, increased hemoglobin
  5. Reticulocyte: 7-8 um, no nucleus, sine ribosomes (blue with freshly blue stain))
  6. Erythrocyte: 7-8 um, only hemoglobin, no ribosomes
27
Q

Explain granolopoiesis (granulocytes formation)

A
  1. Myoblasts: common precursor, 12-14 um, no granules, cytoplasmic blebs
  2. Promyelocyte: 16-24 um, large nucleus, azurophilic granules (not specific)

Nutrophils, eosinophils, or basophilic

  1. Myelocyte: 10-12 um, condensed founded nucleus, specific granules
  2. Metamyelocyte: kidney-shaped nucleus, specific granules
  3. Band (stab): C-shaped nucleus, specific granules
  4. Mature form: neutrophil, eosinophil, basophil
28
Q

How much granulocytes are formed in a day?

A
  1. About 800,000 neutrophils, 170,000 eosinophils, 60,000 basophils per day
  2. Controlled by cytokines, takes about 11 days
29
Q

Explain monocytopoiesis

A

Monocyte formation

  1. Monoblasts: large, undifferentiated cells
  2. Promonoblasts: 16-18 um, kidney shaped nucleus, azurophilic granules
  3. Monocytes: “sky” blue cytoplasm, kidney shaped nucleus
  4. Enter the circulation, proceed to tissue spaces, differentiate into macrophages
30
Q

Explain thrombopoietin (platelet formation)

A
  1. Controlled by thrombopoietin
  2. Megakaryoblast: 25:40 um, endomitosis, polyploid (about 32N)
  3. Megakaryocyte: 40-100 um, large multi-lobed nucleus
  4. Platelets are formed from fragments of megekaryote cytoplasm (1000’s per cell)
  5. Platelet demarcation cells
31
Q

Explain lymphopoiesis

A

Lymphocyte formation

  1. Colony forming units (CFU)- lymphocyte (B= bursa equivalent; T= thymus)
  2. Lymphoblasts: large, undifferentiated cells
  3. Prolymphocytes: medium-sized cells, condensing chromatin, no cell surface antigens
  4. Some migrate from bone marrow to thymus, divide and differentiate to T-cells
  5. Others remain in bone marrow, differentiate to B-cells , migrate to lymph tissues
32
Q

What adult stem cell plasticity?

A

Ability of stem cells to form specialized cell types of other tissues
-useful for cell-based therapies

33
Q

What are the hematopoietic stem cells?

A

Neurons and glial stem cells

Skeletal muscle cells

Cardiac muscle cells

Liver cells

34
Q

What are the bone marrow stromal cells?

A

Cardiac muscle cells

Skeletal muscle cells

35
Q

What are the neural stem cells?

A

Blood cells

Skeletal muscle cells

35
Q

What are the neural stem cells?

A

Blood cells

Skeletal muscle cells

Cardiopulmonary Renal (35 decks)

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