Unit 7 Study Guide Flashcards
Viscosity of blood
- blood is 4-5 more thick than water
- depends upon the amount of dissolved substances in the blood relative to the amount of fluid.
- increases if amount of substances increases or if amount of fluid decreases
Temperature of blood
- blood is about 1 degree celsius higher than measured body temperature
pH of blood
- around 7.35-7.45
- plasma proteins have a three-dimensional shape that is dependent upon H+ concentration
hemopoiesis
- formation and development of formed elements (blood cells)
erythropoiesis overview
- erythrocytes form in red bone marrow in response to erythropoietin
- circulate in blood for about 120 days
- aged erythrocytes are phagocytized by macrophages in the liver in spleen
erythropoiesis process
- start with a hemocytoblast (blood stem cell)
- goes through myeloid line and becomes a reticulocyte
reticulocyte
- have no organelles except some ribosomes
- continues to produce hemoglobin through protein synthesis
- mature while circulating in blood vessels
leukopoiesis
- granulocyte, monocyte, and lymphocyte maturation
- all three types of granulocytes are derived from a myeloid stem cell stimulated by multi-CSF and GM-CSF to form a progenitor cell
granulocyte line
- develops when the progenitor cell forms a myeloblast under the influence of G-CSF.
- differentiate into one of three types of granulocytes
monocyte line
- develops when the progenitor cell forms a mono blast under the influence of M-CSF>
- forms a promonocyte that differentiates and matures into a monocyte
lymphocyte line
- derived from lymphoid stem cells
- differentiate into B-lymphoblasts and T-lymphoblasts
- mature into lymphocytes
thrombopoiesis
- formation of platelets
- from myeloid stem cell, committed cell becomes a megakaryoblast
- matures under influence of thrombopoietin to form a megakaryocyte
- produce long extensions called proplatelets
proplatelets
extend through blood vessel wall and are sliced into platelets
molecular structure of hemoglobin
- consists of four molecules called globes
- two are called alpha chains and the other two are beta chains
- all contain a heme group composed of a porphyrin ring with an iron ion in its center
- oxygen binds to Fe2+ in heme groups for transport in the blood
- Has four Fe2+ and is capable of binding four molecules of oxygen
recycling and elimination of erythrocyte components
- phagocytized by macrophages in the liver and spleen
- three components of hemoglobin are separated
fate of globulin proteins
- broken down into amino acids and enter the blood
- some may be used to make new erythrocytes
fate of iron
- stored in liver and attached to ferritin and hemosiderin
- transported by transferrin into red bone marrow as needed for erythrocyte production
- small amounts are lost in feces, sweat, and urine as well as injury and menstruation
fate of heme without iron
- converted to biliverdin then bilirubin
bilirubin
- transported to liver and then released as a component of bile in small intestine
- converted to urobilinogen in small intestine
urobilinogen
- some is absorbed back into the blood and converted to urobilin and excreted in the urine
- most continues to the large intestines where it is modified and expelled in feces.
ABO blood typing
- ABO blood group consists of surface antigens called A and B
- the presence or absence of A antigen or B antigen determines the ABO blood type.
Type A blood
- erythrocytes with surface antigen A only.
- produces anti-B antibodies
Type B blood
- erythrocytes with surface antigen B only
- produces anti-A antibodies
Type AB blood
- has erythrocytes having both surface antigens A and B
- produces neither anti-A nor anti-B antibodies