Control of Respiration 1. Medulla Oblongata Sets the rhythmic pace of respiration. - Dorsal Respiratory Group – inspiration. - Ventral Respiratory Group – forced breathing.

2. Pons (the Pontine respiratory centers) For ‘fine tuning’ and protection of respiration. Apneustic center For strong, sustained inspiration. Used for ‘overdrive’ when breathing deep. Pneumotaxic center Inhibits apneustic and inspiratory centers. Sets limits to over inflation of lung.

Sensory Receptors - regulate respiration. Mechanoreceptors Detect changes in lung volume (inflation of lungs). Chemoreceptors Detect changes in PCO2, pH, PO2 of blood and CSF.

Central Chemoreceptors in medulla oblongata Peripheral Chemoreceptors 1) Aortic bodies (in aorta) 2) Carotid bodies (in carotids)

Central N.S. Peripheral Chemoreceptors Medulla Oblongata 1.  PCO2 2.  pH 3.  PO2 Diaphragm PCO2  Ventilation  pH  PO2

Carotid and Aortic bodies detect changes in: PCO2 [H+] PO2 levels in arterial blood Central Chemoreceptors in Medulla detect changes in: PCO2 levels in CSF. * But do so via [H+] in CSF.