PHYS20009 Lecture Notes - Lecture 9: Parasympathetic Nervous System, Sympathetic Nervous System, Cardiac Output

• School: University of Melbourne
• Department: Physiology
• Course: PHYS20009
• Professor: Charles

Document Summary

* central command cerebrocortical (motor cortex) activation of the sympathetic nervous system and inhibition of the parasympathetic nervous system. * reflexes that originate in contracting muscle mechanoreceptors and chemoreceptors. * metabolism accumulation in exercising muscle e. g. * baroreceptor reflex less sensitive during exercise. * regulation of blood flow to organs is regulated by vasoconstriction or vasodilation. To increase blood flow there is vasodilation and to decrease there is vasoconstriction. * blood flow to skeletal muscles significantly increases. Control of respiratory responses to exercise oxygen consumption: * initially when we start exercising, there will be an increase in activity that is not met by the current oxygen content/consumption (oxygen deficit amount of oxygen required by muscles is not matched by the respiratory rate). * ventilation increases due to an increasing needs during exercise (not due to carbon dioxide changes) * increase in ventilation under exercise is not dependent on arterial oxygen, arterial carbon dioxide, venous oxygen or changes in arterial ph.