Blood Study Guide Flashcards
(41 cards)
Define the Cardiovascular System
refers to the system only the heart and blood vessels
Define Arteries, Capillaries, Veins
Arteries- transport blood away from the heart
Capillaries- permeable microscopic vessels between arteries and veins; sites of exchange between blood and body tissues; this is how oxygen and nutrients exit the blood and how carbon dioxide and cellular wastes enter the blood.
Veins- transports blood towards the heart.
Describe the general functions of blood
Transport- O2, CO2 nutrients, wastes, hormones, and stem cells
Protection- Inflammation, limit spread of infection, destroy microorganisms and cancer cells, neutralize toxins, and initiate clotting
Regulation- Fluid balance, stabilizes pH of ECF, and temperature control
Describe the components of blood: plasma and formed elements
Adults have 4-6 L of blood.
Blood is a liquid CT consisting of cells and extracellular matrix
Plasma- matrix of blood; clear, light, yellow fluid
Formed elements: Blood cells and fragments; RBCs, WBCs, Platelets
Describe the General characteristics of blood
Volume in adult body: Females- 4-5 L, Males 5-6 L
Volume/Body Weight: 80-85 mL/kg
Mean Temperature- 38 degrees C (100.4 degrees F)
pH- 7.35- 7.45
Viscosity (relative to water)- Whole Blood: 4.5- 5.5; plasma: 2.0
Osmolarity: 280-296 mOsm/L
Mean salinity (mainly NaCl): 0.9%
What percentage of centrifuged blood is occupied by formed elements and plasma?
Plasma- 55%
Buffy Coat- < 1% (white blood cells and platelets)
(Formed elements) Red Blood Cells- 45% Hematocrit
Define Hematocrit
% of RBC in a sample; 45% of the total
Describe the composition of plasma
92% water Plasma proteins- 5%= albumins, globulins, fibrinogen electrolytes Wastes Nutrients, vitamins, hormones Gases- N2, O2, CO2
Define Colloid.
What are the Plasma Proteins?
Define colloid osmotic pressure
Define and describe the importance of blood viscosity and osmolarity
Briefly explain why high or low levels of viscosity or osmolarity are a problem.
Colloid- a mixture composed of protein within water, where the protein ranges from 1-100 nanometers; appears opaque or milky.
Plasma Proteins include:
Albumins: Smallest most abundant, contribute to viscosity and osmolarity; influence blood pressure, flow, and fluid balance.
Globulins: circulating antibodies, provide immune system functions; alpha, beta, gamma globulins
Fibrinogens: precursor of fibrin threads that help form blood clots
Colloid osmotic pressure- osmotic pressure exerted by plasma proteins; responsible for drawing fluids into the blood and preventing excess fluid loss from blood capillaries into the interstitial fluid.
Viscosity(thickness)- resistance to a fluid to flow, resulting from the cohesion of its particles; slow-moving
Osmolarity- the total molarity of those dissolved particles that cannot pass through the blood vessel wall.
importance of blood viscosity- increased viscosity opposes blood flow and raises blood pressure
Importance of blood osmolarity-
too high (hypertonic)- blood absorbs too much water, therefore, increasing blood pressure,
too low(hypotonic)= too much water stays in tissue, BP drops, resulting in edema.
Optimum osmolarity is achieved by regulation of NA ions, proteins, and RBCs
Describe the 4 major plasma proteins and their functions: Albumins, Globulins, Fibrinogens, and Regulatory proteins.
Albumins: Smallest most abundant, contribute to viscosity and osmolarity; influence blood pressure, flow, and fluid balance.
Globulins: circulating antibodies, provide immune system functions; contain alpha, beta, gamma globulins
Fibrinogens: precursor of fibrin threads that help form blood clots
Regulatory: includes both enzymes to accelerate chemical reactions in blood and hormones being transported throughout the body to target cells.
What are the formed elements?
Erythrocytes(RBCs)- 95.1%
Leukocytes (WBCs- neutrophils, basophils, monocytes, lymphocytes)-0.1%
Platelets-4.8%
Define hematopoiesis, hemocytoblast, erythropoiesis, myeloid stem cell, proerythroblast, erythroblast, normoblast, reticulocyte. What hormone stimulates RBC production.
hematopoiesis- production of blood, especially its formed elements.
hemocytoblast- hematopoietic stem cells; produces myeloid line (erythrocytes, leukocytes) and lymphoid line (lymphocytes).
erythropoiesis- erythrocyte production
myeloid stem cell- what erythropoiesis begins with; ; under the influence of multi CSF forms a progenitor cell
proerythroblast- large, nucleated cell
erythroblast- smaller than proerythroblast; produces hemoglobin in cytosol
normoblast- smaller cell again with more hemoglobin in cytosol, but nucleus ejected.
reticulocyte- lost all organelles except some ribosomes; still can produce hemoglobin through protein synthesis.
the hormone that stimulates RBC production is erythropoietin.
Describe Leukopoiesis and thrombopoiesis
Leukopoiesis- Production of white blood cells
Thrombopoiesis- production of platelets
Describe an erythrocyte
Diameter-7.5 micrometers
2.0 micrometers thick at rim
Most of the organelles lost
Lacks mitochondria- anaerobic formation to produce ATP
Lacks nucleus and DNA- no protein synthesis or mitosis
Describe the 2 principle functions of erythrocytes
- Carry O2 from lungs to cells tissue
2. Pick up CO2 from tissues and bring to lungs
Define the hemoglobin. Briefly describe its color, abundance in RBC, and its 3 functions
hemoglobin- red-pigmented protein that transports O2 and CO2.
33% in RBC. Hb is bright red when oxygenated and darker red when deoxygenated.
Each Hb molecule consists of:
- 4 heme groups that bind O2 to its Fe and can transport 4 O2 molecules.
- Globin is the protein portion of hemoglobin and binds about 5% of CO2 in blood.
- Globin can also bind Hydrogen ions (H+) which helps buffer the blood and maintain pH.
- Acts as a buffer
Discuss two ways in which a RBC is an example of complexity of structure and function: lack of mitochondria and plasma proteins.
lack of mitochondria- forces RBCs to make ATP exclusively by anaerobic respiration or fermentation so they don’t consume the O2 they are transporting.
Plasma proteins- give membrane durability and resilience; stretch and bend as squeezed through small capillaries.
Describe hemoglobin structures and their gas carrying ability: globins and heme
Each Hb molecule consists of:
- 4 heme groups that bind O2 to its Fe and can transport 4 O2 molecules.
- Globin is the protein portion of hemoglobin and binds about 5% of CO2 in blood.
- Globin can also bind Hydrogen ions (H+) which helps buffer the blood and maintain pH.
- Acts as a buffer
Why is iron essential in RBC? Describe the stomach’s role with dietary iron.
Iron= key nutritional requirement; it is lost daily through urine, feces, and bleeding.
Men 0.9 mg/ day and women 1.7 mg/day
Low absorption rate of iron requires consumption of 5 to 20 mg/ day.
Dietary iron: ferric (Fe3+) and ferrous (Fe2+)
Stomach acid converts Ferric into absorbable ferrous.
Briefly describe the roles of the proteins transferrin and ferritin in iron metabolism.
ferratin- binds Fe2+ and transports it to small intestine.
Transferrin- transports iron to bone marrow, liver, and other tissues.
Define biliverdin and bilirubin. Define urobilinogen, stercoblin, and urobilin.
biliverdin- green pigment heme is converted to
bilirubin- yellow pigment biliverdin is converted to
urobilinogen- brown feces
stercoblin- brown pigment expelled from body as a component of feces
urobilin- yellow pigment excreted by kidneys.
Explain what determines a person’s blood type. Define antigen (agglutinogen) and antibodies (agglutinins), and agglutination.
Surface antigens (agglutinogens), ABO blood group and Rh protein, determine the blood type.
antigen (agglutinogen)- complex glycolipid molecules on surface of RBC cell membrane that activate an immune response; genetically unique to individual; cell identity markers; determine blood type.
antibodies (agglutinins)- circulates in plasma; can form an antigen-antibody complex; antibodies in the plasma that bring about transfusion mismatch.
agglutination- antibody molecule binding to antigens; causes clumping of RBCs.
Explain how a person’s blood types relate to transfusion compatibility. Define a transfusion reaction.
Blood types and transfusion compatibility are a matter of interactions between plasma proteins and erythrocytes.
transfusion reaction- if a person receives mismatched blood plasma bind to their respective surface antigens within the erythrocyte plasma membrane; erythrocytes clump and may block small blood vessels.
Explain what determines a person’s Rh blood group.
The patient is considered Rh+ if having D antigen (agglutinogens) on RBCs.
