Control of the heart Flashcards
What does increased blood pressure do?
Stretch carotid arteries and aorta causing barrel receptors to increase their pastorate of action (potential generation)
What is action potential?
Contracted by glossopharyngeal nerve and vaguest nerve to the cardio regulatory and vasomotor centres in the medulla oblongata
What does increase of stimulation from the barrel receptor cause?
the cardio regulatory centre increase parasympathetic stimulation to the heart
What does the cardiovascular do since there’s an increase stimulation from the barrel receptor?
Decreases sympathetic stimulation to the heart which decreases heart rate and stoke volume
What does vasomotor centre do to the sympathetic stimulation?
Decrease it now blood vessels cause vasodilation
What does vasodilation and decrease HR+ Stroke volume cause?
Brings the elevated blood pressure back to normal
What if initial problem was decrease in blood pressure?
Then the activities and effects of the barrel receptor, cardiovascular centre and vasomotor centre would be the opposite of what is illustrated
What does the cardia centre in the medulla oblongata do?
Maintain balance between sympathetic and parasympathetic division of the autonomic nervous system
What is the function of the barrel receptors?
Recognise change in pressure
What does the cardiac centre do?
responds to barrel receptors reflexes
How can increase impulses from cerebrum and hypothalamus influence heart rate through?
Emotions
Exercise
body temp
concentration of certain ions
What can high levels of K cause?
Decrease HR- life threatening
What can high levels of Ca do?
Increase HR
What can low levels of Ca do?
Decrease HR
