Author Question: Which accessory muscles are active during resting and active inspiration and pull up on all the ribs ... (Read 155 times)

melly21297 · **on:** Jul 16, 2018

Which accessory muscles are active during resting and active inspiration and pull up on all the ribs expanding the thorax?

a. External intercostals
b. Internal intercostals
c. Scalenes
d. Sternocleidomastoid s

Question 2

What is the lowest level on the spinal cord that an injury could cause diaphragmatic impairment or paralysis?

a. C3
b. L2
c. S5
d. T4

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

Answer to Question 1

ANS: A
The external intercostals (Figure 9-22) originate on the upper ribs and attach to the lower ribs. The fibers of these muscles run at an oblique angle between the ribs. When they generate tension, they lift the ribs upward and cause the thoracic cavity to enlarge the thorax.

Answer to Question 2

ANS: A
Spinal cord injuries at or above the level of the third cervical vertebrae result in diaphragmatic paralysis.