Question

1. Abductors enable efficient bipedal motion by contracting parts of the gluteals that attach to the ilium and allow humans to step on one foot at a time.

a. True

b. False

2. The oldest members of the human lineage are the Australopithecines.

a. True

b. False

Answer 1

Answer 1

true

because abductions, particularly the gluteus medius and minimus, are active on the side of the leg that is in contact with the ground. This is to resist the tendency of gravity to cause a downward movement of the hip on the opposite side In addition, the paraspinal muscles and lateral muscles of the trunk are active on the side of the swinging leg to resist the downward movement of the iliac crest on that side.

Answer 2

true

because australopithecines means 'southern ape.' It is an extinct genus of members of the human family tree.