Laboratory 4: The Axial Skeleton

Exercises 9 & 10

Objectives

Laboratory 4 is a general introduction to bones and the skeleton (Ex. 9) and a detailed examination of the bones in the axial skelton (Ex. 10).

Background

The skeleton is divided into the axial skeleton and the appendicular skeleton. The axial skeleton consists of bones located around the body’s center of gravity- the head, thorax, and abdominopelvic midline. The appendicular skeleton consists of bones of the shoulders, hips, and limbs.

Exercise 9: Overview of the Skeleton

You are required to know all figures from your manual. You not required to memorize the definitions of bone markings, however, familiarity with these terms may help you to learn the names of specific bone marks in the near future. Work through Exercise 9 examining bones as needed. Review the histology of compact bone and cartilage, if necessary, but we have already covered these in recent labs.

Exercise 10: The Axial Skeleton

Work through Exercise 10, using the figures to identify bones and their bone markings. Learn to distinguish among the three types of vertebrae. Know all figures, however, we will limit the number of bone markings you must memorize. Below is a list of bone markings you DO NOT NEED TO KNOW. You may want to put a line through these in your lab manual. IF IT IS NOT LISTED BELOW, YOU ARE REQUIRED TO KNOW IT. Fig. 10.2: external occipital protuberance, incisive fossa, foramen ovale, foramen lacerum, carotid canal, stylomastoid foramen, jugular foramen, inferior nuchal line, superior nuchal line. Fig. 10.3: tuberculum sellae, hypophyseal fossa, posterior clinoid process, dorsum sellae, internal acoustic meatus, chiasmatic groove, optic foramen, anterior clinoi process, foramen rotundum, foramen ovale, foramen spinosus, foramen lacerum, jugular foramen, hypoglossal canal. Fig. 10.4: optic foramen, superior orbital fissure, foramen rotundum, foramen ovale, foramen spinosum, pterygoid processes. Fig. 10.5: orbital plate, perpendicular plate, middle nasal concha, left lateral mass. (note: we do not own a disarticulated ethmoid bone. You will see diagrams only). Fig 10.6: (a) inferior nasal concha, middle nasal concha, (b) superior nuchal line, external occipital protuberance, inferior nuchal line. Fig 10.7: (a) orbital surface, frontal process, anterior nasal spine, (c) horizontal plane, orbital surface, vertical plane. (note: we do not own disarticulated palantine bones). Fig. 10.13: (a) anterior arch, anterior tubercle, posterior tubercle, (b) fovea dentis, anterior tubercle, anterior arch, posterior tubercle, posterior arch. You must be able to recognize vertebrae C1 and C2. Fig. 10.14: (a) transverse lines, ventral sacral foramina, (b) dorsal sacral foramina, sacral hiatus.