![]() The main role of erythrocytes is transporting O 2 and CO 2. The blood serum is the plasma without the blood cotting agents.Į rythrocytes give the red color to the blood because of its high hemoglobin content, a protein containing iron in its structure. The red color of blood is the result of the high content in hemoglobin of erythrocytes, which is darker when the oxygen level is low. Plasma constitutes the rest of the blood. The proportion of leukocytes is lower than 1 %. The proportional volume of eythrocytes out of the total blood volume is known as hematocrit. In human males, blood contains 47 % of eyrhtrocites, while in human females is about 41 %. Plasma is the lightest component and remains in the superficial part of the centrifugated. Leukocytes and platelets are found a little higher forming a whitish layer. The heaviest elements are erythrocytes, that fall to the bottom of the centrifugation tube. The different components of the blood can be separated by density gradient centrifugation. In mammals, erythrocytes lack nucleus so that all nucleated cells in the blood are leukocytes.įigure 2. All blood cells develop from a common stem cell that, in adult animals, is found in the bone marrow.įigure 1. Most blood cells are erythrocytes (99% of the cells). Leukocytes can be granular leukocytes: neutrophils, basophils and eosinophils, and agranular: lymphocytes and monocytes. There are also cell fragments in the blood referred as platelets. It also contains the cells of the immune system, that use the circulatory system to be transported and attack pathogen in any tissue of the body.īlood cells are classified in two groups: erythrocytes or red cells, and leukocytes or white cells (Figures 1 and 2). Blood contributes in the repairing of wounds by sealing the damages with erythrocytes, platelets and plasma, i.e., blood clotting. For example, it keeps relatively constant the body temperature and pH of tissues. Blood contributes to the general body homeostasis. It is also the main communication pathway for chemical signals, like hormones, between distant cells in the body. Wasting products are transported to the kidney and lungs. Blood transports nutrients and oxygen from intestine and the lungs, respectively, to the rest of the body. The following are three salient functions. This higher value is a consequence of the friction of the blood inside the blood vessels, mainly in the small diameter blood vessels.īlood has many functions. The blood temperature is about 38 ✬, one degree higher than the general body temperature. A 70 kg body contains around 5 to 6 liters of blood. The volume of blood in the human body depends on the body size. Heart beating and body movement push the blood through the cardiovascular system, which reaches every part of the body. Blood is the liquid found inside blood vessels and heart. Atlas of Plant and Animal Histology.īlood is regarded by many authors as a specialized type of connective tissue composed of cells, cell fragments and a liquid extracellular matrix known as blood plasma.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |