BIOL 460 1st Edition Lecture 29 Outline of Last Lecture I Starling s Forces II Regulation of Breathing III Chemoreceptors a central b peripheral c Hypoventilation d Hyperventilation Outline of Current Lecture I Hemoglobin and O2 Transport II CO2 Transport III Acid base Balance Current Lecture 1 Hemoglobin and O2 transport a Hemoglobin i 4 polypeptides ii Globin protein iii Hemo heme group porphorin ring with iron in center iv Iron forms covalent bond with O2 b Oxyhemoglobin hemoglobin O2 c Deoxyhemoglobin hemoglobin only d Deoxyhemoglobin O2 oxyhemoglobin e CO carboxyhemoglobin i Bond is 200x greater than O2 ii Treat by putting poisoned individual in hyperbaric O2 change These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute f Two factors determine shift of reaction i ppO2 ii Bond affinity strength between O2 and heme group g oxyhemoglobin saturation tells how much hemoglobin is oxyhemoglobin i Normal 97 ii Use arterial blood iii Spectrophotometer redder more hemoglobin iv Pulse oximeter shines 2 lights into blood and determines how much of each wavelength is absorbed algorithm uses this info to determine how much hemoglobin is bonded to O2 occurs with pulse rate h O2 carrying capacity in blood determined by hemoglobin i Anemia less O2 than normal because of lack of hemoglobin ii Polycythemia more hemoglobin in blood than normal iii Kidneys determine how much hemoglobin is in blood 1 Secrete erythropoietin 2 Bone marrow produces more RBCs i Loading reaction i Higher ppO2 ii Stronger bond affinity j Unloading reaction i Lower ppO2 ii Weaker bond affinity k Oxyhemoglobin dissociation curve see notes 16 33 i S shaped ii Flat at high and low ppO2 iii Exercise drops ppO2 slightly l Bond affinity i Affected by pH ii Bohr effect iii Temperature higher weaker bond iv Happens during exercise as well m 2 3 bisphosphoglycerate i Erythrocytes have no mitochondria ii Only make ATP through fermentation iii 1 3 bisphosphoglycerate 2 3 bisphosphoglycerate mutase 2 3 bisphosphoglycerate iv shift to right bond affinity is weakened v produced with anemia or if someone moves to a high altitude less oxyhemoglobin 1 oxyhemoglobin inhibits 2 3 bisphosphoglycerate mutase 2 no OHb to inhibit with anemia or altitude change 2 CO2 Transport a 10 dissolved in plasma b 20 bonds to globin of hemoglobin producing carbaminohemoglobin c 70 transported as bicarbonate d RBCs contain carbonic anhydrase i ii iii iv v vi Accelerates rxn CO2 H2O H2CO3 H HCO3Can accelerate in either direction Protons combine with globin part of hemoglobin enhancing Bohr effect HCO3 exits RBC CL enters chloride shif Everything is reversed exactly when CO2 reaches lungs 3 Acid base balance a pH of blood of arterial plasma 7 35 7 45 i deviation is serious and can interfere with enzyme activity ii lower pH acidosis iii higher pH alkalosis b Carbonic acid H2CO3 i volatile acid b c if reversed it can be a converted into gas c Other acids i Metabolic acids non volatile 1 Can t be converted into gas
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