Question

What is the advantage of dorso-ventral (D-V) flexion of the spine in quadrupeds that have erect postures, such as mammals? Select all that apply.

a. stride length decreases

b. stale air can move from the left lung to the right lung (& vice versa) via a visceral pump

c. pulmonary ventilation can be synchronized through alternating negative and positive pressure states in the lungs

d. elastic energy stored in the curved spine increases the speed of the limb arc

e. movement of the tendons in the backbone that surround the intestines improves digestion

f. stride length increases

Answer 1

Answer: Choices c, d, e, f

Explanation: The dorso-ventral movement of the flexion utilizes many muscles of the thorax including those involved in spine movement, curvature, digesion and pulmonary respiration. The ability of erect posture mammalas to enhance their stride length owing to the dorso-ventral flexion further enhances the utilization of their torsional muscles and minimizes the use of four limbs for walking. These systems of muscles and bones help the individuals to walk and maintain their erect posture.