Which of the Following are the Accessory Muscles of Respiration

Question

Which of the following are the accessory muscles of respiration (used in forced exhalation)?
A) Intercostals and diaphragm
B) Sternocleidomastoid and trapezius
C) Internal intercostals and the abdominal muscles
D) Pectoralis major and serratus anterior

Accepted Answer

The internal intercostal muscles and abdominal muscles are accessory muscles of respiration used in forced exhalation. The intercostal and diaphragm muscles are primarily used during normal respiration. The sternocleidomastoid and trapezius muscles are accessory muscles of respiration used in forced inhalation. The pectoralis major and serratus anterior muscles are not involved in respiration.