a) The human skeleton is-- b) The skull protects-- c) There are twelve pairs-- d) The pelvis protects-- e) Limb bones have-- f) The 33 bones of the backbone-- g) The spinal column-- h) The backbone is-- i) The vertebrae are separated-- j) Heart and stomach muscles-- k) The biceps and triceps-- ANSWERS i) protects the spinal cord. ii) strong and flexible. iii) a framework of over 200 bones. iv) attachments for muscles. v) of ribs vi) the brain. vii) are called vertebrae. viii) the lower abdomen. viii) are involuntary muscles. viiii) by pads of gristle. x) are involuntary muscles