QuestionSBA
QuestionChoice
This is incorrect. The serratus anterior does attach to the ribs, but its function is to rotate the scapula to allow the arm to be raised over 90 degrees.
10026183
d
Serratus anterior
QuestionChoice
This is incorrect. In inspiration, the diaphragm contracts and flattens, this increases the vertical diameter of the thoracic cavity. The diaphragm does not move the ribs.
10026182
c
Diaphragm
QuestionChoice
This is correct. The external intercostal muscles connect the ribs in such a way that the contraction of the muscles lifts the ribs and rib cage, expanding the anteroposterior dimensions of the ribcage.
10026180
a
External intercostal muscles
QuestionChoice
This is incorrect. The internal intercostal muscles depress the ribs in forced expiration, they do not have a role in inspiration.
10026181
b
Internal intercostal muscles
QuestionChoice
This is incorrect. The sternocleidomastoid rotates the head to the opposite side and flexes the neck.
10026184
e
Sternocleidomastoid
Concept
Chapter
2693
3778
The role of chest muscles in breathing
Topic
150
Respiratory physiology
17634
A 37 year old man attends the emergency department with an acute asthma exacerbation. They have an increased respiratory rate and are seen to be using accessory muscles to help them breathe.

Which of the following muscles raises the ribcage and sternum during inspiration?
a