19. Blood elements: red cells and their diseases Flashcards
What is the function of Blood?
-To transport materials between cells and external environment
What are the components of Blood?
-Plasma
-Erythrocytes(red blood cells)
-Leukocytes(white blood cells)
-Platelets
What is an Erythrocyte and what is it important for?
-Red blood cells
-Important in O2 transport
What are Leukocytes?
-White Blood cells
-immune systems mobile defence units
What are platelets, what is it important for?
-Cell Fragments
-Important in Hemostasis
What is Hematocrit(HCT)?
The number of Erthrocytes in blood expressed as a percent of total blood volume
What formula do you use to calculate Hematocrit(HCT)?
HCT=(Volume of RBC/Volume of blood)x100
What does the range of Hematocrit (HCT) depend on?
-Age and after adolescence the sex of the individual
What are the functions of Plasma ?
-To carry and distribute various molecules around the body
-To absorb and distribute heat
-To transport proteins
What are the components of Plasma ?
-Water
-Electrolytes
-Nutrients
-Gases
-Hormones
-Waste
-Plasma proteins
What is the purpose of water in Plasma?
It is the transport medium.
What electrolytes are in the Plasma and what is the purpose?
-Na+,Cl-,HCO3-,K+,Ca2+
-Membrane excitability; osmotic distribution between ECF and ICF; buffer pH changes.
What are some examples of nutrients in the Plasma?
-Glucose
-Amino Acids
-Fats
-vitamins
What is an example of gas in the plasma and what is It important for?
-CO2
-Important for acid-base balance
How much percent of the total plasma weight does the plasma protein compose ?
-Compose 6% to 8% of plasma’s total weight.
What are the functions of Plasma protein?
-Maintain osmotic pressure in capillaries to avoid fluid loss (general)
-Act as buffers to maintain blood pH(general)
-Assist transport of water insoluble compounds
-Blood clotting factors
-Protection
What are the 3 groups of Plasma Protein ?
-Albumins
-Most abundant plasma proteins
-Contribute most to colloid osmotic pressure
-Globulins
-Three subclasses
-Alpha,Beta, Gamma
-Fibrogen
-Key factor in blood clotting
Where is Hemoglobin(Hb) found and what does it contain ?
-Found only in red blood cells
-Pigment containing iron
-Appears reddish when oxygenated
-Appears bluish when deoxygenated
What are the two groups that Hemoglobin(Hb) consist of?
-Globin Protein
-Protein composed of four highly folded polypeptide chains
-Heme groups
-Four iron containing nonprotein groups
-Each is bound to one of the polypeptides
What is the primary role of Hemoglobin?
-To carry O2
What are some Hemoglobin Disorders?
-Lead poisoning ->blocks heme synthesis
-Porphyria->group of different disorders caused by defects in heme production
-Thalassemia->defective global synthesis –>anemia
-Methemoglbinemia
- this when Oxidized Fe3+ os present rather Fe2+
What is the function of Erthrocytes ?
-To transport oxygen(5 billion cells/ml)
-Contain no nucleus, organelles, or ribosomes BUT have enzymes such as carbonic anhydrase and glycolytic enzyme
-Flexible membrane
What does the flexible membrane in Erythrocytes do?
-Allows RBCs to travel through narrow capillaries without rupturing in the process
-8um diameter can squeeze through 3um capillaries
What is Erythropoiesis?
-it is the process where Erythrocytes are produced and erythrocytes survive about 120 days
