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liver and constitutes 60% of the total protein content of the blood. Globulins are a class of protein that comprise 36% of plasma proteins (they function in lipid transport, as steroid hormones, and in blood clotting). Fibrinogen is another protein synthesized in the liver, and is essential to formation of blood clots. With respect to its cellular constituents, the proportion of blood volume that is composed of erythrocytes is termed the hematocrit. The cellular constituents of the blood are produced within bone marrow. The most abundant cell type are the erythrocytes (45% of blood volume). These red blood cells contain large quantities of hemoglobin. Hemoglobin is essential for transport of oxygen and carbon dioxide in the blood. These cells no longer function like other cells since they lack nuclei, mitochondria, and ribosomes. They have a relatively short lifespan (120 days) and are stimulated to proliferate by erythropoietin. The remainder of the cellular components of blood include leukocytesand platelets. Leukocytes function to defend the body against microorganisms and other foreign materials. Unlike red blood cells, these cells are not restricted to the circulation and can be found in most tissues. Platelets are important in blood clots. They are derived as cellular fragments from megakaryocytes.Diff: 6 Page Ref: 4362) Oxygen and carbon dioxide are poorly soluble in plasma so they require erythrocytes for their transport in blood. Describe how erythrocytes transport these gases.ion.Diff: 6 Page Ref: 43814
3) Erythrocytes have no nucleus or organelles. Therefore, the lifespan is short. Describe the lifecycle of erythrocytes.