Name:
Pelvic girdle/ pelvis/ pelvic bones    
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 Structure:
Six pelvic bones comprise the rectangular structure, the pelvic girdle,
that connects the posterior sacral vertebra
of the axial skeleton above, and the
upper leg below. The pubis is more cartilaginous than osseous in the frog.
The urostyle (coccyx) extends beyond and above the last sacral vertebra,
and is not one of the pelvic bones. The bones of the pelvic girdle are
flat, irregular bones, with a thin, outside cortex, and an inner, cancellous
part where blood cell formation (hematopoiesis)
occurs. In primates, the pelvis has two distinct portions, the upper cone-shaped
false pelvis, and the true pelvis,
the tubular-lower portion.
 Function:
During a leap, the bony frame of the pelvis is pushed upward by the lower
limbs, raising the trunk upward. The ball-in-socket
hip joint makes this possible. Ventrally, the pelvic girdle supports
the muscles of the upper body which contains several of the internal
organ systems in a peritoneal cavity, and below, the muscles
of the thigh hook onto the pelvic girdle
to produce leg movements. The ballistic angle
determines how far the frog will jump.
Questions:
<questions>
Evaluation:
For me, this frame was:
- Difficult
- OK
- Fun
- Easy
- Too Easy
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