Hematopoiesis Flashcards
formation and development of blood cells
Hematopoiesis
PRENATAL HEMOPOIESIS
Yolk-sac phase of hemopoiesis:
It begins in the …………………of gestation.
3rd week
PRENATAL HEMOPOIESIS
Hepato-splenic phase:
during the…………………… Both hepatic and splenic continue until the end of gestation.
second trimester
Bone marrow phase or myeloid phase:
o It begins in the ……………… of pregnancy.
3rd trimester
After birth, hemopoiesis takes place only in the…………….and………………….
red bone marrow and lymphatic tissues.
most of marrow in adults is………………., is present in ……………………………
inactive yellow bone marrow,
diaphysis of long bones
Active red bone marrow In most of .,……………
fetus bones
Active red bone marrow In the adults……………
- Epiphysis of the long bones
- Ribs
- Body of vertebrae
Yellow inactive BM Is yellow in color
due to its ………………………….
high content of fat cells
In fetus: most of the marrow is ………………
the red type
Functions of Red active type
- Production of blood cells.
- Destruction of old RBCs.
- Storage of iron in
macrophages.
Functions of Yellow inactive type
- Storage of fats.
- In time of need as in
hemorrhage or
hypoxia, it can change
into active red type.
Structure of BM:
- CT stroma
- Blood sinusoids
- Hematopoietic cells
Stroma of Red bone marrow is a meshwork of …………. ,………..,…………….,………………
reticular cells, reticular fibers and collagen type I.
…………………….. are formed by a
discontinuous layer of endothelial cells
surrounded by macrophages.
Blood sinusoids
