Chapter 7, Problem 1CP

On What basis is the skeleton grouped into the axial and appendicular divisions?

Summary Introduction

To review:

The basis for the division of skeleton into axial and appendicular divisions.

Introduction:

The skeletal system contains different types of bones, which form the framework of the body. Bones protect the internal organs and help in the movement of body parts. Two hundred and six bones are found in the adult human body; the size and the shape of the bones differ greatly and each type has a specific function. The skeleton is divided into two main groups namely axial as well as an appendicular skeleton.

Explanation of Solution

Bones present in the longitudinal axis are grouped as an axial skeleton, while the appendicular skeleton is composed of the bones, which form girdles that connect the limbs to the axial skeleton, upper limbs, and lower limbs. The axial skeleton contains 80 bones, which include major structures like a hyoid bone, skull, vertebral column, as well as thorax. The appendicular skeleton contains 126 bones, which include major structures like a pectoral girdle, pelvic girdle, lower limbs, and upper limbs.

The axial skeleton protects and supports the organs in the ventral and dorsal cavities. It also creates the surface, on which the muscles could attach. The function of appendicular skeleton is to connect the limbs to the axial skeleton.

Conclusion

Thus, the skeleton is divided on the basis of the group of bones, which are present in the longitudinal axis and the bones, which form the appendages or extremities and girdles that joins limbs with the axial skeleton.