BIOM20002 Lecture Notes - Lecture 54: Nitric Oxide, Organelle, Central Chemoreceptors
Document Summary
At lungs where there is low pco2, co2 moves off hb and blood out into alveoli. Co2 and ph and o2 are monitored by body to control ventilation. These are sensativ to co2 and h+ ions. If these increase the chemoreceptors increase ventilation to brathe out more co2. Pripheral chemoreceptors: located in artic arch and carotid sinus (same plac as baroreceptors). Shouldn"t be stimulated normally since blood coming from lungs has 100mmhg of po2. We regulate co2 because we want to maintain ph of plasma. Also co2 is a better indication of metabolic output. However o2 is always being loaded in at the lungs so it is difficult to use it to determine metabolic rate in the periphery. Peripheral chemoreceptors sensitive to co2 too but centrals are more sensitive and will respond first. They only kick in if there is a problem. Carbonic anhydrase in csf converts it to h+ so central chemoreceptors can respond to them.
