Stages of Hematopoiesis Flashcards
Enumerate the types of Hematopoiesis
- Prenatal Hematopoiesis
- Adult Hematopoiesis
- Extramedullary Hematopoiesis
Enumerate the Prenatal Stages of Hematopoiesis
- Totipotent
- Pluripotent
- Multipotent
happens right after the ovum fertilized, first few hours there’s a development of mesoblastic stage
Totipotent
development of embryo to fetus
Totipotent
HSCs become present several days after fertilization
Pluripotent
development of any cell types except they cannot develop in fetus
Pluripotent
derived from the pluripotent stem cells and limited only to specific cells that forms tissue
Multipotent
Bone marrow restricted (long bones are responsible to blood production)
Adult Hematopoiesis
Bone marrow is made up of
osteoblast and osteoclast
(bone-forming cells)
osteoblast
(bone-resorbing cells)
osteoclast
Is the only site of erythropoiesis, myelopoiesis, thrombopoiesis and lymphopoiesis
Bone Marrow
a delicate balance exist between developing bone marrow space trabecular bone and the developing infant’s need for blood cells and liver or spleen remains available because of its hematopoietic capability
1st year of life
rate of bone marrow growth exceed the need for blood cells therefore, active marrow sites are replaces with areas of fatty reserve and fat first develops in the long bones (5-7 years old adipose tissues become more abundant)
4th year of life
process of replacing the active marrow by the adipose tissue
Retrogression
T/F. active yellow marrow will scattered and will be capable of reverting back again to red marrow in case of increased demand
True
the only active hematopoietic sites are in the pelvis,
vertebrae, ribs, scapulae, sternum, skull and proximal extremities of the long bones
18th year of life
Contains developing erythroid, myeloid, and megakaryotic
Bone Marrow
located in the cavities of the cortical bones
Bone marrow
Cortical bones cavities consists of
trabecular bone (honey comb)
Types of Bone marrow:
RED MARROW
YELLOW MARROW
Site of blood cell development
RED MARROW
Hematopoietically active bone
RED MARROW
Comprises appro. 50% of the marrow/cavity space
RED MARROW
Hematopoietic sites are sternum, skull, scapular, vertebrae, ribs, pelvic bones and proximal ends of long bones (adult)
RED MARROW
Hematopoietically inactive bone
YELLOW MARROW
Mix up of adipose cell (adipocytes), undifferentiated mesenchymal cells and macrophage
YELLOW MARROW
T/F. RED AND YELLOW marrow should have approximately unequal amounts
False, must equal amounts
develops in the embryo by the hollowing out of the skeletal bones forming a central cavity
Bone marrow
In this cavity develops a primitive, undifferentiated cell known as
hemocytoblast or stem cell
T/F. All blood formed elements ultimately develop from this undifferentiated precursor
True
Full developing precursor cells in all stages of
maturation
Released into blood at maturity
Bone marrow
T/F. ONLY mature cells are released normally in Bone marrow
True
First recognizable precursor in each cells is a
blast
requires Peripheral Blood Smear in order to see young cells
Leukemia
due to resorption of cartilage and endosteal bone
Central space
red marrow are active in:
Infancy and Early Childhood
adipocytes are more abundant in:
5 – 7 years old
the process of replacing the active marrow by the adipose tissue during development
Retrogression
- Bone marrow and thymus
- Where T and B cells are derived
Primary Lymphoid tissue
Lymphoid become competent, consist of the spleen and lymph nodes and gut associated lymphoid tissue
Secondary Lymphoid tissue
