HEMATOPOIESIS Flashcards
is the continuous, regulated process of renewal, proliferation, differentiation and maturation of all blood cell lines.
Hematopoiesis
this process result in the formation and specialization of all functional blood cells which are released from the bone marrow into the circulation
Hematopoiesis
mature blood lives has a limited life span , the cell population must be capable of ________ that will sustain the system
self-renewal
what are the phases or sites of hematopoiesis?
Mesablastic, hepatic and myeloid
hematopoiesis is considered to begin around the ___________ of embryonic development after fertilization
nineteenth day
early in embryonic development, cells from the __________ migrate to the ________.
mesoderm, yolk sac
these primitive but _______________ are important in early _________ to produce _________.
transient yolk sac erythroblasts, embryogenesis, hemoglobin
____________ differs from hematopoiesis that occurs later in the fetus and adult in that it occurs ________ (or within developing blood vessels)
Yolk sac hematopoiesis, intravascularly
what are the three types of hemoglobin?
Gower-1, Gower-2 and portland
they are needed for delivery of oxygen to rapidly developing embryonic tissues?
Hemoglobin (Gower-1, gower -2 and portland)
what phase of hematopoiesis does the description fit into?
“it begins around the nineteenth day of embryonic development”
mesoblastic phase
what phase of hematopoiesis does the description fit into?
“ Early in embryonic development, cells from the mesoderm migrate to the yolk sac.”
Mesoblastic phase
it also known as within developing blood vessels
Intravascularly
what phase of hematopoiesis does the description fit into?
“begins at 5-7 gestational weeks and is characterized by recognizable clusters of developing erythroblasts, granulocytes and monocytes colonizing the fetal liver, thymus, spleen, placenta, and ultimately the bone marrow space in the final medullary phase.”
Hepatic phase
what phase of hematopoiesis does the description fit into?
“Hematopoiesis during this phase occurs extravascularly, with the liver remaining the major site of hematopoiesis during the second trimester of fetal life.”
Hepatic phase
the hepatic phase begins in _____________ (weeks )and is characterized by recognizable clusters of developing erythroblasts, granulocytes and monocytes colonizing the fetal liver, thymus, spleen, placenta, and ultimately the bone marrow space in the final medullary phase.”
5 -7 gestational weeks
in the hepatic phase, hematopoiesis occurs __________, with the liver remaining the major site of hematopoiesis during the __________ of fetal life.
extravascularly, second trimester
in the hepatic phase the _______, first fully developed organ in the fetus becomes the major site of T cell production whereas the _________ (organ) produce B cells.
Thymus, kidney and spleen
what phase of hematopoiesis does the description fit into?
“the thymus, the first fully developed organ in the fetus, becomes the major site of T cell production, whereas the kidney and spleen produce B cells.”
Hepatic phase
the ______________ signals the beginning of a definitive hematopoiesis with a decline in the primitive hematopoiesis in the yolk sac. In addition the ________ now begin to appear
developing erythroblasts, lymphoid cells
what organ produces T cells in the fetus stage?
Thymus
What organ produces B cells
kidney and spleen
what phase begins between the fourth and fifth month of fetal development?
Medullary phase or myeloid phase
in what phase does the description fit? “the hematopoietic activity of this stage is apparent of development and the myeloid-to-erythroid ratio gradually approaches 3:1 to 4:1 (normal adult levels)”
medullary phase (myeloid phase)
“by the end of 24 weeks’ gestation, the bone marrow becomes the primary site of hematopoiesis” what phase does the description fit?
Medullary (myeloid) phase
in what month does the medullary (myeloid) phase begin during fetal development?
fourth and fifth month
hematopoietic activity, especially ___________, is apparent during this stage of development and the ____________ ratio gradually approaches 3:1 to ________ (normal adult levels)
myeloid activity, myeloid-erythroid ratio, 4:1
myeloid-to-erythroid ratio of normal adult levels
4:1 ratio
in what week of gestation does the bone marrow become the primary site of hematopoiesis?
24 weeks’ gestation
what happens during the 24 weeks’ gestation period?
the bone marrow becomes the primary site of hematopoiesis
in adults, where does the hematopoietic tissue located?
bone marrow, lymph nodes, spleen, liver and thymus.
what does the bone marrow contain?
Developing erythroid, myeloid, megakaryocytic and lymphoid cells
where does the lymphoid development occur?
in the primary and secondary lymphoid tissue
the primary lymphoid tissue consists of the?
bone marrow, thymus and is where the t and b lymphocytes are derived
the secondary lymphoid tissue where lymphoid cells responds to foreign antigens consists of the?
spleen, lymph nodes and mucosa associated lymphoid tissues
a theory where it describes the origin of the hematopoietic progenitor cells
Stem cell theory
a theory where it suggests that all blood cells are derived from a single progenitor stem cell called pluripotent hematopoietic stem cell
monophyletic theory
the two theories of the stem cell theory?
Monophyletic theory
polyphyletic theory
a theory where it suggests that each of the blood cell lineages is derived from its own unique stem cell. it is also noted as the most widely accepted theory among experimental hematologists.
polyphyletic theory
what does the monophyletic theory suggests?
a theory where it suggests that all blood cells are derived from a single progenitor stem cell called pluripotent hematopoietic stem cell
what does the polyphyletic theory suggests?
a theory where it suggests that each of the blood cell lineages is derived from its own unique stem cell. it is also noted as the most widely accepted theory among experimental hematologists.
in the monophyletic theory, what do you call the single progenitor stem cell that suggest the derivation of the all blood cells?
pluripotent hematopoietic stem cell
(of an immature or stem cell) capable of giving rise to several different cell types.
pluripotent
what are the two major types of morphologically unrecognizable progenitor cells?
uncommitted and committed hematopoietic stem cells
it occurs in the bone marrow and is a complex, regulated process for maintaining adequate number of erythrocytes in the peripheral blood.
Erythropoiesis
what are the two erythroid progenitors?
Burst forming unit - erythroid (BFU-E)
Colony forming Unit - erythroid (CFU-E)
it is the earliest morphologically recognizable erythrocyte precursor in the bone marrow?
pronormoblast
meaning of CFU-GEMM?
Colony Forming Unit Granulocyte, Erythrocyte, Monocyte and Megakaryocyte
the CFU-GEMM gives raise to the earliest colony of RBCs called the _________.
Burst forming unity - Erythroid (BFU-E)
BFU-Es under the influence of interleukin GMCSF, PPO and Kitlygan will develop into?
Colony Forming Unit - Erythroid
serves as a differentiation factor for the CFU-Es and BFU-Es?
Erythropoiesis
they are named for their ability to form colonies on semi solid medium in culture experiments that enable the study of their characteristics and development.
Erythroid progenitors (BFU-E and CFU-E)
they are the earliest committed progenitor gives rise to the large colonies as they are capable multi subunits called burst
Burst forming unit - Erythroid (BFU-E)
what do you call the multi-subunits of a BFU-E?
burst
it gives rise to smaller colonies?
Colony forming unit - Erythroid
How many estimated days does the BFU-E to mature to become CFU-E and the CFU-E to become a pronormoblast?
1 week
it is derived from the BFU-E and CFU-E from pluripotent hematopoietic stem cells.
Pronormoblast
is similar to the other proliferation of the other cell lines. It is the process of encompassing replication, for example division, that increases cell numbers and development from immature to mature cell stages.
Normal blast proliferation
the pronormoblast can be divided to _______ and then it will be divided to the next stage ______.
basophilic, polychromatic normal blasts
What are the criteria used in identification of Erythroid Precursors?
diameter of the cell decreases
diameter of the nucleus decreases more rapidly than the diameter of the cell
nuclear chromatin pattern becomes coarser, clumped and condensed developing a rasp berry appearance
The nucleus becomes quite condense with no parachromatin evident at all
The nucleus is also said to be pyknotic
nucleoli disappears
cytoplasm changes from gray-blue to salmon pink
major function of the red blood cell?
carry oxygen from the lungs to the tissues
acid base buffer
Appearance and characteristic of the RBC
biconcava in shape and distensible
is the first microscopically recognizable precursor cell in erythropoiesis
it is aka Proerythroblast
pronormobalst
after mitosis the pronormoblast forms ?
two basophilic normoblast
is present only in the bone marrow in healthy states
pronormoblast
in the pronormoblast the nucleus to cytoplasm ratio is ?
8:1
describe the nucleus of the pronormoblast?
the nucleus is round to oval, containing one or two nucleoli. Has a purple red chromatin which is open and contains few, if any, fine clumps
describe the nucleus of the basophilic normoblast
the chromatin begins to condense, revealing clumps along the periphery of the nuclear membrane and a few in the interior
describe the nucleus of the basophilic normoblast
the chromatin begins to condense, revealing clumps along the periphery of the nuclear membrane and a few in the interior
describe the appearance of the cytoplasm of the pronormoblast
basophilic
describe the appearance of a basophilic normoblast?
deeply basophilic. Cytoplasm is dark blue because of the concentration of ribosomes and RNA
Ratio of NC of the Basophilic Normoblast
Moderate 6:1
when the basophilic normoblast undergoes mitosis it gives rise to _____________.
two daughter cells
what is detectable in the basophilic normoblast?
hemoglobin synthesis
the basophilic normoblast is present only in the _________________ during healthy states
bone marrow
describe the nucleus of the polychromatic normoblast?
the condensation of chromatin reduces the diameter of the nucleus considerably
describe the appearance of the polychromatic normoblast’s cytoplasm
first stage in which the pink color can be seen as it is associated with the stained hemoglobin
NC ratio of polychromatic normoblast
Moderate
the last stage of polychromatic normoblast contains and is capable of ?
contains nucleus and is capable of mitosis
what is the orthromatic normoblast known as?
Metarubicyte
describe the appearance of the nucleus’ metarubicyte?
the nuclues is completely condensed or pyknotic