Breathing control Flashcards
What two groups of neurons in the medulla oblongata control breathing?
Dorsal respiratory group and ventral respiratory group?
What other section of the brainstem, apart from the medulla oblongata, contains areas responsible for respiration control?
Pons
What areas exist within the brainstem?
Midbrain, Pons, medulla oblongata
What area is responsible for controlling the rate and depth of breathing, as well as feeding into the dorsal respiratory group?
Pneumotaxic centre
What is the current known function of the apneustic centre?
Modulating the breathing cycle
What area is responsible for initiating inspiration?
Dorsal respiratory group
Where is the sensory terminal for the vagus (X) and glossopharyngeal (IX) nerves?
Nucleus tractus solitaris
Where do the efferent (motor) signals from the dorsal respiratory group go?
To the inspiratory muscles
How does the dorsal respiratory group allow for expiration?
There is an intense 2 second period of action potentials that trigger inspiration, followed by a rest period of 3 seconds to allow for expiration.
True or false: during normal, quiet breathing, expiration is an active process
False, it is passive during quiet breathing and only becomes active when there is a need for extra respiratory drive.
Describe the position of the ventral respiratory group in relation to the dorsal respiratory group
Anterior and lateral
What process is the ventral respiratory group involved in?
Active breathing
What types of receptors feedback to the respiratory centre about what is going on in the pulmonary system?
Chemoreceptors, mechanoreceptors, baroreceptors, thermoreceptors
What part of the brain is involved in voluntarily holding your breath?
Cerebral cortex
What centres in the brain may be involved in altering your breathing during emotional stimulus?
Hypothalamus and limbic system.
What is the Hering-Breuer inflation reflex?
Stretch receptors in bronchial airways will signal to “turn off” inspiration drive when tidal volume reaches approximately 1.5L
What are the two types of chemoreceptors?
Central and peripheral
What vessel in the neck are peripheral chemoreceptors located, and what else is this location known for?
Carotid sinus, also where baroreceptors are located to monitor blood pressure
Where can the carotid sinus be found?
Inferior to the bifurcation of the common carotid.
What nerve carries signals from chemoreceptors in the carotid sinus?
Glossopharyngeal nerve (IX)
From where does the vagus nerve (X) interact with peripheral chemoreceptors, and what is significant about this in humans?
Arch of the aorta, they are not used in humans as much as in other animals
Which type of chemoreceptors are faster?
Peripheral
What are the chemo sensitive cells of the carotid bodies called?
Type I glomus
Which pH state are carotid body chemoreceptors more sensitive to?
Acidosis (High H+)