Chapter 18 The Circulatory System Blood 1 What is the purpose of an Erythrocyte RBC The purpose of an RBC is to transport oxygen to the body tissues and to transport carbon dioxide that needs to be discarded 2 What are the constituents of blood plasma and what are their functions The blood plasma contains mostly proteins the three proteins are Albumin Globulins and Fibrinogens The functions of these proteins are clotting defense and transport of other solutes such as iron copper lipids and hydrophobic hormones Electrolytes are a major portion of the blood plasma which contains the bloods sodium Sodium is very important as a solute for the osmolarity of blood and is a major influence for blood volume and blood pressure Transports nutrients absorbed by the digestive tract Carries nitrogenous wastes such as urea which will be excreted by the kidneys to balance out production Gases such as oxygen carbon dioxide and nitrogen Hormones 3 Where is oxygen bound to hemoglobin Oxygen is bound at the Ferrous Ion at the center of a heme group A heme group binds oxygen there is 1 oxygen per heme group There are 4 heme groups in a molecule of hemoglobin which means that hemoglobin contains 4 oxygen atoms 4 With Hemopoiesis hemocytoblasts eventually become Hemopoiesis is the production of blood cells Hemocytoblasts eventually become a variety of specialized cells called colony forming units CFUs are destined to produce one class of formed elements such as platelets RBCs or WBCs 5 What is unique about the RBC The RBC has no nucleus and no organelles It has a biconcave shape It is the only cell in the body that runs on anaerobic respiration 100 of the time Because it has no mitochondria it produces its own ATP 6 What plasma protein is involved with blood clotting Fibrinogen 4 of blood plasma proteins 7 Which plasma protein is responsible for plasma osmotic oncotic pressure Albumins 8 Which plasma protein is found in the highest concentration in the blood Albumins 60 of blood plasma proteins 10 Which plasma proteins function as antibodies Globulins 11 What becomes the name of an immature blood cell that becomes and Erythrocyte Is it a committed cell form An immature RBC is an Erythroblast Yes this is a committed cell form because Erythroblasts multiply and synthesize hemoglobin and the nucleus begins to shrivel and disintegrate 12 Why is RBC biconcave The biconcave shape provides the cell with a larger surface area in order to transport more oxygen 15 What stimulates Erythropoiesis Erythropoiesis begins when the hemopoeitic stem cell becomes an ECFU which has receptors for the hormone erythropoietin which causes ECFU to transform into an immature RBC 16 Where is Erythropoietin produced Erythropoietin is the hormone that stimulates the Erythrocyte colony forming unit ECFU to transform into an Erythroblast It is produced in the kidney 17 What is the Hematocrit The hematocrit is the percentage of whole blood volume composed of Red Blood Cells