The appendicular skeleton is composed of the pectoral girdle?

Analyze the question: The question asks which parts, together with the pectoral girdle, make up the appendicular skeleton.

Concept: The skeleton has two main divisions:

• Axial skeleton: the skull, vertebral column (including the lumbar vertebrae), ribs and sternum. It forms the central axis of the body.
• Appendicular skeleton: the bones of the limbs (appendages) and the girdles that attach them to the axial skeleton.

The appendicular skeleton includes:

1. Pectoral (shoulder) girdle: the scapula and clavicle
2. Fore limbs (arms): the humerus, radius, ulna, carpals, metacarpals and phalanges
3. Pelvic (hip) girdle: the ilium, ischium and pubis
4. Hind limbs (legs): the femur, tibia, fibula, tarsals, metatarsals and phalanges

Checking the options:

• A. pelvic girdle, fore and hind limbs: This completes the list with the pectoral girdle, so it is correct.
• B. pelvic girdle and fore limbs: The hind limbs are missing, so it is incomplete.
• C. lumbar vertebrae and pelvic girdle: The lumbar vertebrae belong to the axial skeleton, so it is wrong.
• D. lumbar vertebrae, fore and hind limbs: This also includes the lumbar vertebrae, so it is wrong.

**Answer: A.

Exam tip: Remember "Appendicular = Appendages + Attachments". It covers the limbs and the girdles (pectoral and pelvic) that attach them. Anything on the central axis, such as the skull, vertebrae, ribs and sternum, is axial. Whenever you see "vertebrae" in an option for the appendicular skeleton, you can eliminate it straight away.