Classify each of the bones in the chart below as either long, short, flat, or irregular by placing a check mark in the appropriate column

Classify each of the bones in the chart below as either long, short, flat, or irregular by placing a check mark in the appropriate column. Also use a check mark to indicate whether the bone is a part of the axial or the appendicular skeleton. Use Figure 71 as a guide.

Long
Short
Flat
Irregular
Axial skeleton
Appendicular Skeleton
Sternum
Radius
Calcaneus (tarsal bone)
Parietal bone (cranial bone)
Phalanx (single bone of a digit)
Vertebra

The Correct Answer and Explanation is:

Here is the completed classification chart:

Explanation (300+ words):

To accurately classify bones, we rely on their shape and location in the body. The human skeleton is divided into the axial skeleton (central core: skull, vertebrae, ribs, sternum) and the appendicular skeleton (limbs and girdles).

1. Sternum: This flat bone is located in the central chest and connects the ribs via cartilage. Because it is broad and plate-like, it is classified as a flat bone. Since it forms part of the thoracic cage, it belongs to the axial skeleton.
2. Radius: The radius is one of the two long bones in the forearm. It is longer than it is wide and has a shaft, which characterizes long bones. Because it is part of the arm, it is part of the appendicular skeleton.
3. Calcaneus: This is a short bone, meaning it is approximately as wide as it is long. Found in the foot (specifically the heel), it is a tarsal bone, which is part of the appendicular skeleton.
4. Parietal bone: These are flat bones found on the sides and roof of the skull. Since they are part of the cranium, they belong to the axial skeleton.
5. Phalanx: The bones of the fingers and toes are long bones despite being relatively small. They have a cylindrical shape with a shaft, fitting the criteria for long bones. Because they are part of the limbs, they belong to the appendicular skeleton.
6. Vertebra: These bones are irregular in shape—neither flat, long, nor short. Each vertebra has a complex structure with many projections for muscle attachment. As part of the vertebral column, they are part of the axial skeleton.

This classification helps anatomists understand structure-function relationships and provides guidance in medical contexts such as injury assessment and surgical planning.