Author Question: Which of the muscles below when stimulated will contract and push up on the diaphragm? 1. External ... (Read 50 times)

mmm · **on:** Jul 16, 2018

Which of the muscles below when stimulated will contract and push up on the diaphragm? 1. External intercostals 2. External obliques 3. Internal obliques 4. Rectus abdominous

a. 1, 2, and 3 only
b. 1 and 4 only
c. 2, 3, and 4 only
d. 1, 2, 3, and 4

Question 2

The abdominal muscles can actually contribute to inspiration by:

a. contracting at end-exhalation.
b. contracting at end-inhalation.
c. causing a cough.
d. increasing end-inspiratory lung volume.

sailorcrescent · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

ANS: C
When the abdominal wall muscles contract, they compress the abdominal cavity. This forces the diaphragm upward and compresses the thoracic cavity. The abdominal muscles include pairs of external oblique, internal oblique, transverse abdominis, and rectus abdominous muscles (Figure 9-27).

Answer to Question 2

ANS: A
The abdominals can also contribute to inspiration by contracting at end-exhalation. This reduces end-expiratory lung volume, so the chest wall can recoil outward, assisting the next inspiratory effort.