In the human embryo, the first site of blood formation is the yolk sac. Later in embryonic life, the liver becomes the most important red blood cell-forming organ, but it is soon succeeded by the bone marrow, which in adult life is the only source of both red blood cells and the granulocytes. Their job is to transport oxygen to the body's tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts give rise to all of the formed elements in blood. Erythroid (red blood) cells are the first cell type to be specified in the postimplantation mammalian embryo and serve highly specialized, essential functions throughout gestation and postnatal life. The existence of 2 developmentally and morphologically distinct erythroid lineages, primitive (embryonic) and definitive (adult), was described for the mammalian embryo more than a century ago. Cells of the primitive erythroid lineage support the transition from rapidly growing embryo to fetus, whereas definitive erythrocytes function during the transition from fetal life to birth and continue to be crucial for a variety of normal physiologic processes. Over the past few years, it has become apparent that the ontogeny and maturation of these lineages are more complex than previously appreciated. In this review, we highlight some common and distinguishing features of the red blood cell lineages and summarize advances in our understanding of how these cells develop and differentiate throughout mammalian ontogeny.
Answer:
balance
Explanation:
because balance helps your body if not locomotor
Water. is probably a good one
Answer:
cardiovascular endurance
Explanation: i think cardiovascular endurance is most important because it helps improve many risk factors for heart disease. it lowers blood pressure, maintains weight loss, and makes the heart stronger and more efficient so it can deliver more blood to the muscles.
1.)keep clean and make sure to get the sopa made to be used for that part of the body
2.)remeber to change menstral suplise often
3.) if you are sexually active be sure to go to your doctor to get checked
4.) clean a little more than you normally would if you are on your menstral cicle
5.) if you are having pains in your reproductive system go to your doctor and tell your doctor
6.) if you take birth control don't skip because it can have very negetive efficts
7.) and of course take care of the rest of your body because no matter how . much you do the other ways it is point less unless you take care of your health
