Search results
Results from the WOW.Com Content Network
In developing embryos, blood formation occurs in aggregates of blood cells in the yolk sac, called blood islands. As development progresses, blood formation occurs in the spleen, liver and lymph nodes. [13] When bone marrow develops, it eventually assumes the task of forming most of the blood cells for the entire organism. [3]
Components that are essential for osteoblast bone formation include mesenchymal stem cells (osteoblast precursor) and blood vessels that supply oxygen and nutrients for bone formation. Bone is a highly vascular tissue, and active formation of blood vessel cells, also from mesenchymal stem cells, is essential to support the metabolic activity of ...
The bone marrow produces the cellular elements of the blood, including platelets, red blood cells and white blood cells. While much information can be gleaned by testing the blood itself (drawn from a vein by phlebotomy ), it is sometimes necessary to examine the source of the blood cells in the bone marrow to obtain more information on ...
Hematopoietic stem cells (HSCs) are the stem cells [1] that give rise to other blood cells.This process is called haematopoiesis. [2] In vertebrates, the first definitive HSCs arise from the ventral endothelial wall of the embryonic aorta within the (midgestational) aorta-gonad-mesonephros region, through a process known as endothelial-to-hematopoietic transition.
An osteocyte, an oblate shaped type of bone cell with dendritic processes, is the most commonly found cell in mature bone. It can live as long as the organism itself. [1] The adult human body has about 42 billion of them. [2] Osteocytes do not divide and have an average half life of 25 years.
Many human blood cells, such as red blood cells (RBCs), immune cells, and even platelets all originate from the same progenitor cell, the hematopoietic stem cell (HSC). [1] As these cells are short-lived, there needs to be a steady turnover of new blood cells and the maintenance of an HSC pool. This is broadly termed hematopoiesis. [2]
A bone is a rigid organ [1] that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, and enable mobility.
It contains the growth plate, the part of the bone that grows during childhood, and as it grows it ossifies near the diaphysis and the epiphyses. The metaphysis contains a diverse population of cells including mesenchymal stem cells , which give rise to bone and fat cells, as well as hematopoietic stem cells which give rise to a variety of ...