Muscles of Respiration

what muscles are involved in respiration?

diaphragm, external intercostals, internal intercostals, innermost intercostals, transverses thoracic

origin of the diaphragm

sternal part: xiphoid process and costal cartilages

costal part: costal margins and lower ribs

lumbar part: vertebral bodies of L1-L3

insertion of the diaphragm

central tendon

innveration of the diaphragm

phrenic nerve

action of the diaphragm

pulls central tendon downward during inspiration

attachment points of the external intercostal muscles

inferior border of the rib above and superior border of the rib below

innveration of the external intercostal muscles

intercostal nerves

action of the external intercostal muscles

elevate ribs

points of attachment for the internal intercostal muscles

inferior border of the rib above and superior border of the rib below

innervation of the internal intercostal muscles

intercostal nerves

action of the internal intercostal muscles

depress the ribs

point of attachment for the innermost intercostal muscles

inferior border of the rib above and superior border of the rib below

innveration of the innermost intercostal muscles

intercostal nerves

action of the innermost intercostal muscles

weakly depress the ribs

origin of the transversus thoracic

inner surface of the sternum

insertion of the transversus thoracic

inner surface of the costal cartilages

innervation of the transversus thoracic

intercostal nerves

action of the transversus thoracic

weakly depress the ribs