Ch.17
What is the purpose of T lymphocytes? What is the purpose of the B lymphocytes?
T lymphocytes cells act against virus-infected cells and tumor cells. B cells give rise to plasma cells, which produce antibodies
Why do males have more red blood cells than females? Explain.
Testerone enhances EPO production resulting in higher red blood cell count in males
What do nitric oxide and prostacyclin do? Explain.
They prevent platelet aggregation in undamaged tissue and restrict aggregation to the site of the injury
What is anemia?
a condition in which the blood has abnormally low oxygen carrying capacity
What is heparin?
anticoagulant used clinically for pre and postoperative cardiac care
The structure and function of red blood cells work together to maximize the amount of oxygen that a red blood cell can carry. Explain.
biconcave shape-huge surface area relative to volume, 97% of hemoglobin, no mitochondria, ATP production is anaerobic, no O2 is used in generation of ATP
Overproduction of ABNORMAL white blood cells occurs in two conditions - infectious mononucleosis (mono) and leukemia. Mono is caused by a virus and usually clears up after rest and time. Leukemia causes red bone marrow to become consumed with producing abnormal white cells. Therefore, fewer red blood cells are made - leading to anemia, and the wbc's that are rapidly released to the bloodstream are immature and non-functional, leading to impaired immune functioning. With leukemia, the more dangerous, acute condition is found more commonly in _____________________________, while the chronic condition is found mostly in __________________________________________.
children, older people
List three situations where a drop in blood oxygen levels would trigger production of rbc's.
1) Polycythemia vera- is a disease in which the bone marrow produces an overabundance of RBCs. 2) Erythropoietin - a substance produced by the kidneys, triggers production of RBCs by the bone marrow. 3)Dehydration- The Hgb level is a measure of the concentration of Hgb in the blood. Therefore, if the volume of the blood is decreased, the Hgb level will rise, even when the number of RBCs has not changed.
If a blood vessel wall breaks, a chain of events happens to achieve "hemostasis" (stoppage of bleeding). There are three main steps in hemostasis. List and describe these three steps.
1) Vascular spasm- smooth muscle contracts causing vasoconstriction 2) Platelet plug formation- injury to linining of vessel exposes collagen fibers; platelets adhere 3) Coagulation- fibrin forms a mesh that traps red blood cells and platelets, forming the clot
List the white blood cells from most numerous to least numerous. List the type of white blood cell and the main function of each.
1) neutrophils-phagocytize bacteria 2) lymphocyte- mount immune response by direct cell attack or via antibodies 3) monoctye- phagocytosis; develop into macrophages in the tissues 4) eosinophil- kill parasitic worms, complex role in allergy and asthma 5) basophil- release histamine and other mediators of inflammation******Granculytes (BEN) Agranculytes (LM)
What is the normal pH of blood (ballpark number)? What is the average volume of blood in adult humans (ballpark number)?
7.35-7.45, 5 liters
What is clot retraction? Explain.
Actin and myosin in platelets contract within 30-60 minutes. Platelets pull on the fibrin strands, squeezing serum from the clot
Blood plasma, the liquid portion of blood, is 90% water. Blood plasma contains over 100 different solutes dissolved in the water. Name some of the types of solutes found in the blood plasma.
Albumin, globulions, and fibrinogen
What is polycythemia? Describe some causes for this condition.
An abnormal excess of eyrthocytes that increases blood viscosity. Polychythemia vera (bone marrow cancer), secondary polychythemia (when less O2 is available), blood doping
Describe three causes of anemia.
An insufficient number of red blood cells, low hemoglobin content, and abnormal hemoglobin
An ion that is needed in almost all stages of clot formation is ______________ ion.
Ca^2+
Blood has three important functions. Describe each (do a good job here - you might see a question like this again): • Distribution of: • Regulation of: • Protection from:
Distriution of O2 and nutrients to body cells, metabolic wastes to the lungs and kidneys for elimination. Regulation of body temperature by absorbing and distributing heat.. Protection against blood loss and infections.
How is the formation of red blood cells regulated? Explain. (What hormone? Produced by what organ? When? What happens?)
Eyrthoprotein is the hormone and is produced in the kidneys and the liver plays a small role. Hemorage or increased red blood cell destruction reduces red blood cell numbers. More rapid maturation of commited bone marrow cells and increased circulating reticulocyte count in 1-2 days
Why is it important to have enough iron in your diet? Explain.
It is essential for hemoglobin synthesis. The human body needs iron in order to produce new red blood cells, which in turn carry oxygen around the body.
Why is it important to have enough vitamin B12 and folic acid in your diet (in terms of blood supply)?
Necessary for DNA synthesis for cell divison
The normal life span of red blood cells is about 100-120 days. What happens to red blood cells when they become old and worn out? Explain.
Old red blood cells become fragile and hemoglobin begins to degenerate and marcophages engulf dying red blood cells in the spleen
What is diapedesis? How does this relate to white blood cells? Explain.
Passage of white blood cells through intact vessel walls into tissue. White blood cells are able to slip out of the capillary blood vessels and the circulatory system is simply their means of transport to areas of the body where they are needed to mount inflammatory or immune response.
The formation of RED blood cells is called _______________________________________. During the process of forming red blood cells, the following occurs: Stem cells called __________________________________ are converted into "committed cells" called ________________________________________. These cells become erythroblasts which undergo three phases: First ________________________________ are made; then __________________________________ accumulates in the cell; next the ________________________________ is ejected from the cell. At this point, a cell called a __________________________________ enters the bloodstream, where it matures into an erythrocyte, within a few days.
erythropoises, hemocytoblast, proerythoblast, ribosome synthesis, hemoglobin, nucleus, reticulocyte
The name for red blood cells is _________________________________. The name for white blood cells is ____________________________________. The name for platelets is ___________________________________.
eyrthocytes, leukocytes, thrombocyte
What is leukocytosis? What does it indicate? Explain.
it is a white blood cell count over 11,000/mm3. The high count indicates viral or bacterial infection, leukocytosis is a normal response to bacterial or viral invasion
What makes up the buffy coat that is found between the blood plasma and the red blood cells in a spun sample of blood?
leukocytes and platelets
An abnormally low count of white blood cells is called _______________________________________. It is normally caused by drugs, in particular glucocorticoids (steroids) and anticancer drugs.
leukopenia
Platelets are fragments of large cells called _____________________________________. Formation of platelets is regulated by a hormone called ____________________________________.
megakaryocytes, thrombopoietin
White blood cells are the only true cells in blood. Explain.
only white blood cells are "true" or "complete" cells in terms of having a nucleus.Red blood cells lose their nucleus and other organelles as they develop from blood stem cells.
What is the hematocrit? What is the normal value (ballpark number)?
percent of blood volume in red blood cells, 45%
What is fibrinolysis?
process that removes unneeded blood clots when healing has occured
Coagulation is the formation of a blood clot. In the process of forming a clot, the following steps are involved: Prothrombin activator is formed. Prothrombin is converted into _______________________________. Then fibrinogen is converted into ____________________________. Prior to the production of prothrombin activator, a bunch of clotting factors are involved. Most of these clotting factors are proteins produced in the ____________________________. A vitamin that is needed to produce several of these clotting factors is vitamin _______________. There are several forms of hemophilia (bleeder's disease) caused by missing clotting factors. The type of hemophilia depends on which clotting factor is missing.
thrombin, fibrin mesh, liver, vitamin K
The formation of blood cells is called __________________________________________. This process occurs where?_____________________________________.
hematopoiesis, occurs in red bone marrow of axial skeleton, girdles and proximal epiphyses of humerous and femur