Muscles of Respiration

Question 1

Diaphragm

Answer 1

A: Draw down the central tendon of the diaphragm, increase the volume of the thoracic cavity during inhalation.
O:
Costal attachment: inner surface of lower six ribs
Lumbar attachment: upper two or three lumbar vertebrae.
Sternal attachment: inner part of xiphoid process
I: Central tendon
N: Phrenic (C3,C4, C5)

Question 2

Intercostals

Answer 2

A:
External intercostals: assist with inhalation by drawing the ribs superiorly, increasing the space of the thoracic cavity
Internal intercostals: assist with exhalation by drawing the ribs inferiorly, decreasing the space of the thoracic cavity.
O: Inferior border of the rib above
I: Superior border of the rib below
N: Thoracic