What does the "pump handle" movement of rib pairs 2 through 7 achieve?
A) Anchor of the upper chest for diaphragmatic contraction
B) Diminish of the energy wasted by inefficient muscular contraction
C) Increase in the anteroposterior diameter of the chest
D) Increase in the lateral dimensions of the chest

Question

Quizplus · Accepted Answer

Ribs 2 through 7 move simultaneously about two axes As each rib rotates about the axis of its neck, its sternal end rises and falls. This movement increases the anteroposterior thoracic diameter in what is commonly referred to as a "pump handle"-like motion.

What Does the "Pump Handle" Movement of Rib Pairs 2