pulmonary ventilation

breathing

is also called pulmonary ventilation

-inspiration = breath in = inhale

-expiration = breath out =exhale

how is pulmonary ventilation accomplished

changing thoracic cavity/ lung volume

thoracic cavity

area above diaphragm

muscles involved in breathing

diaphragm and intercostals

diagphram contraction 

inspiration- flattens the thoracic cavity increases lung volume, drawing air in.

change in volume = change in pressure

high Volume = low pressure

low volume = high pressure

diagphram relaxation

expiration - domes (rasises) the thoracic cavity, decreasing lung volume and forcing air out.

external intercostals

raises the rib cage during inspiration

internal intercostals

lowers the rib cage during forced expiration

high pressure

triggers expiration