chapter 18 A&P 2 for test
18.2a.7 Identify the various types of plasma proteins and explain the general function of each.
(1) Albumins-From liver -helps maintain blood volume and pressure and acts as transport proteins(2) Globulins- transport some water-insoluble molecules, hormones, metals, ions also acts as an antibody(3) Fibrinogen - Contributes to blood clot formation - During clotting, form long fibrin strands to close wound - Plasma with clotting proteins removed(4) Regulatory proteins-enzymes and some hormones to accelerate chemical reactions
objective 18.4a.22
- Sudden constriction of blood vessels - Reduces blood loss from broken vessel - Lasts from few to many minutes - Greater vasoconstriction with greater vessel damage - Caused by serotonin and thromboxane A2 from platelets and chemicals from damaged tissues
18.3d.20. Explain the structure and function of platelets (thrombocytes).
-Membrane-enclosed cellular fragments without nucleus -Formed by megakaryocytes pinching off part of cytoplasm -Serve important role in blood clotting -Circulate for 8 to 10 days -30% stored in spleen thrombocytopenia- abnormally small number of platelets in blood, inhibits clotting
18.1c.3 List the three components of a centrifuged blood sample.
1. Erythrocytes, Buffy Coat, Plasma
18.1b.2 Name six characteristics that describe blood and explain the significance of each to health and homeostasis.
1.Color-bright red if oxygen rich and dark red if oxygen poor2.Plasma concentration-determines whether fluids move into or out of plasma by osmosis3.Temperature-1 degree higher than measured body temperature, moves heat to maintain homeostasis4.Volume-about 5 liters in adult, males more than females and normal volume essential for maintaining blood pressure5. Viscosity-4 to 5 times thicker than water and depends on amount of dissolved substances in blood6.Blood pH-plasma is slightly alkaline and between 7.35-7.45 and protein shape dependent upon hydrogen concentration
Objective xx. Describe anemias and polycythemias.
Anemia• percentage of functioning erythrocytes lower than normal • Delivers too little oxygen-symptoms of lethargy, shortness of breath, pallor, palpitations - Polycythemia• Excessive percentage of erythrocytes in blood • Increases viscosity of blood and strains heart • can be caused by-chronic hypoxia (smoking) -dehydration -increased EPO -unregulated erythrocyte growth
18.4d.7 27. Explain the process of clot retraction and fibrinolysis.
Clot retractionoccurs as clot is formingactinomyosin, contractile protein within plateletscontracts and squeezes the serum out of developing clotmakes clot smallerSpeeds healing process as damaged tissues are pulled closer togetherFibrinolysisLAST STEP IN CLOTTING degradation of fibrin strands by plasminbegins within 2 days after clot formationoccurs slowly over a number of days as wound is repaired
18.3a.9 Define hemopoiesis and explain the role of colony-stimulating factors.
Continual production of formed elements -Occurs in red bone marrow of certain bones Colony-stimulating factors- Leukopoietic growth factors (except erythropoietin) Multi-colony-stimulating factor (multi-CSF)• increases formation of erythrocytes, all granulocytes • increases formation of all monocytes, platelets- Granulocyte-macrophage colony-stimulating factor (GM-CSF)• accelerates formation of all granulocytes and monocytes- Granulocytes colony-stimulating factor (G-CSF)• stimulates formation of granulocytes- Macrophage colony-stimulating factor (M-CSF)• stimulates production of monocytesColony-stimulating factors (continued)- Thrombopoietin• stimulates production of platelets (thrombocytes)- Erythropoietin (EPO)• hormone produced primarily by kidneys (small amount by liver) • Stimulates erythropoiesis
18.3b.14 list the events by which erythrocyte production is stimulated
Controlled by hormone, erythropoietin (EPO)• produced primarily in kidney • liver small producer - EPO stimulation• Testosterone in males stimulates (higher hemocrit) • decreased blood O2 or increased O2 demand (altitude, exercise, blood loss, etc.)• detected by chemoreceptors in kidney • EPO released and travels to red bone marrow • stimulates myeloid cells to increase erythrocyte production
objective 18.3b.16
Due to specific surface antigens, proteins project from plasma membrane of erythrocyte, may be recognized by antibodies appear spontaneously- no prior exposure needed, have implications for blood transfusion, pregnancy
18.1c.5 name the three formed elements of the blood and compare their relative abundance
Erythrocytes-44% Buffy coat- less than 1 % plasma 55%
18.3b.15 Explain the process by which erythrocyte components are recycled.
Fe2+ component in hemoglobin• transported to liver by blood protein: transferrin • bound to storage proteins: ferritin, hemosiderin • stored mainly in liver and spleen• Fe2+ transported to red bone marrow as needed for erythrocyte productionHeme group (minus Fe2+)• converted within macrophages into green pigment, biliverdin • eventually converted into yellowish pigment, bilirubin-transported by albumin to liver -Bilirubin secreted as component of bile into small intestin
18.5.28 Describe when and how blood is formed in the embryo, fetus, childhood and adulthood.
Hemocytoblasts develop from primitive stem cellsOriginate in yolk sac of embryocolonize liver, spleen, thymuslater begin to colonize red bone marrowby birth, all production in bone marrowHemopoiesisoccurs in most bones in young childrenrestricted to selected bones in axial skeleton in adulthoodHeads of femur and humerus, flat bones of hip and head
18.4c.24 Compare and contrast the intrinsic pathway and the extrinsic pathway for activating blood clotting.
Initiation of coagulation cascadeTwo separate pathways to initiate blood clottingintrinsic and extrinsic pathwaysConverge to the common pathway Common pathway begins with Factor XIntrinsic pathwayinitiated by damage to inside of vessel wallinitiated by platelets contacting collagentakes 3 to 6 minutesExtrinsic pathwayinitiated by damage outside of vesselusually takes about 15 seconds
18.3a.12 Summarize the process by which platelets are formed in thrombopoiesis.
Megakaryoblast produced from myeloid stem cell - Forms megakaryocyte under influence of thrombopoietin• large size and multilobed nucleus • produces thousands of platelets per second • Platelets circulate in blood vessels and play a role in clotting
18.5.29 List some conditions that occur with the bone marrow and blood in the elderly.
Older bone marrowreplaced with fat as individuals ageolder individuals more likely to become anemicmay produce fewer and less active leukocyteshas more prevalent leukemias of certain types
18.2a.6 Define colloid osmotic pressure.
Osmotic pressure exerted by plasma proteins• prevent loss of fluid from blood as moves through capillaries, helps maintain blood volume and blood pressure, Can be decreased with disease
18.3c.19 Explain what is meant by a differential count and how it is clinically useful.
Performed when leukocytes elevated to diagnose disease • Measures amount of each type of leukocyte
18.4b.23 Describe what happens when platelets encounter damage in a blood vessel.
Platelet plugFormed from platelets arriving at injury siteendothelial wall normally smooth and coated with prostacyclinDamage vessel - collagen fibers in vessel wall exposedplatelets stickassisted by von Willebrand factor, plasma proteinsStart clogging up break
18.3a.10 Describe the process of erythropoiesis
Process of erythrocyte production - Make up more than 99% of formed elements - Requires iron, B vitamins, amino acidsBegins Erythropiesis with myeloid stem cell - Forms progenitor cell under influence of multi-CSF - Loses most organelles, produces much hemoglobin (Hb) - Becomes erythrocyte• plasma membrane "bag" containing Hb for O2transport• Hb also binds CO2• Carbonic anhydrase catalyzes CO2HCO3-+ H+
18.3b.13 Describe the structure of erythrocytes.
Small, flexible formed elements - Commonly referred to as red blood cells - Lack nucleus and cellular organelles - Have biconcave disc structure (like inverted Frisbies) - Plasma membrane with enclosed hemoglobin molecules (about 33% of volume)
Describe the general functions of blood. 18.1a.1
Transport gas (o2 and co2), nutrients (cho, protein, fats, vitamins, minerals), hormones, waste products, regulate ph, fluid balance, body temperature, protection (cells of immune system, antibodies)
18.4a.21 Describe vascular spasm, the first phase of hemostasis.
When a blood vessel is injured, the first phase in hemostasis to occur, which begins immediately, is a vascular spasm, whereby damage to smooth muscle within the vessel wall causes smooth muscle contraction. This contraction results in vasoconstriction (i.e., the blood vessel lumen narrows) and thus limits the amount of blood that can leak from this damaged vessel. The spasm continues during the next phase, as both platelets and the endothelial cells of the blood vessel wall release an array of chemicals to further stimulate the vascular spasms. The vascular spasm phase usually lasts from a few to many minutes. The more extensive the vessel and tissue damage, the greater the degree of vasoconstriction.
18.4c.25 Describe events in the common pathway.
activated by extrinsic or intrinsic pathwayFactor X the first stepInvolves activation of thrombin and fibrin Positive feedback regulationevents continuing until clot is formed Size of clot limitedClotting ends as clotting agents run out
Objective xx. Describe the two main types of leukemia
cancer of leukocytes abnormal, non-functioning cells, replace normal cells-Acute leukemia• rapid progression • death typically within months in children and young adults • 80-90% complete remission with treatment (about ½ relapse)-Chronic leukemia• slower progression • in middle-aged and older individuals • 10-20% survival for 5+ years
18.3c.18 Distinguish between granulocytes and agranulocytes and compare and contrast the various types.
granulocytes with visible granules seen with light microscope • agranulocytes with smaller granules not visible with light microscope- Granulocytes• neutrophils, eosinophils, basophils- Agranulocytes• Lymphocytes (T, B, NK), monocyte
18.2b.8 List dissolved substances in plasma by category.
organic and inorganic molecules and ions -Include electrolytes, nutrients, gases, waste products -Polar or charged substances dissolving easily -Nonpolar molecules requiring transporter protein
Objective 18.4c.26 Discuss the survival response that occurs when blood loss exceeds 10%
survival response that occurs when blood loss exceeds 10% If greater than 10% of blood lostsympathetic responseincreased vasoconstriction, heart rate, force of heart contractionblood redistributed to heart and braineffective in maintaining blood pressure until 40% of blood lost
18.3a.11. Compare the production of granulocytes, monocytes, and lymphocytes in leucopoiesis.
• neutrophils, basophils, eosinophils- Monocytes • Monocytes in circulation, • Some become macrophages in tissues- Lymphocytes• B lymphocytes (B cells) • T lymphocytes (T cells), NK cells
18.3c.17 Explain the main function of leukocytes.
•Help defend body against pathogens- Cell to cell attack (cell-mediated immunity) or produce antibodies (antibody-mediated immunity)
