Download Pectoral Girdle and Upper Limb Lab

Pectoral Girdle
And Upper Limb
Laboratory Exercise 15
Background
The pectoral girdle consists of two clavicles and two scapulae. These parts
support the upper limbs and serve as attachments for various muscles that move
these limbs.
Each upper limb includes a humerus, a radius, an ulna, eight carpals, five
metacarpals, and fourteen phalanges. These bones form the framework of the
arm, forearm, and hand. They also function as parts of levers when the limbs are
moved.
Materials Needed
Textbook
Articulated human skeleton
Disarticulated human skeleton
Purpose of the Exercise
Examine the bones of the pectoral girdle and upper limb and identify the major
features of these bones.
Procedure
1. Label figures 15.1, 15.2, 15.3, 15.4, 15.5, and 15.6.
2. Examine the bones of the pectoral girdle and locate as many features as
possible.
3. At the same time, locate the corresponding surface bones and features of
your own skeleton.
4. Examine the bones and features of the upper limb
5. Identify these same bones and features on your own skeleton.
6. Complete Parts A, B, and C.
Critical Thinking Application
Why is the clavicle a bone that can easily fracture?
1
Figure 15.1 Label the bones and features of the right shoulder and upper limb
(anterior view).
Figure 15.2 Label the posterior surface of the right scapula (left) and the lateral
aspect of the right scapula (right).
2
Figure 15.3 Label the anterior surface (left) and the posterior surface (right) of
the right humerus.
Figure 15.4 Label the major features of the right radius and ulna (anterior view).
3
Figure 15.5 Label the bones and features of the right elbow (posterior view).
Figure 15.6 Label the bones and groups of bones in this anterior view of the
right hand.
4
Part A
Complete the following statements:
1. The pectoral girdle is an incomplete ring because it is open in the back
between the _______________.
2. The medial ends of the clavicles articulate with the _______________ of the
sternum.
3. The lateral ends of the clavicles articulate with the _______________ of the
scapulae.
4. The _______________ is a bone that serves as a brace between the
sternum and the scapula.
5. The _______________ divides the scapula into unequal portions.
6. The tip of the shoulder is the _______________ of the scapula.
7. At the lateral end of the scapula, the _______________ curves anteriorly and
inferiorly from the clavicle.
8. The glenoid cavity of the scapula articulates with the _______________ of
the humerus.
5
Part B
Match the bones in column B with the bones and features in column A. Place the
letter of your choice in the space provided.
___ 1. Capitate
a. Carpals
___ 2. Capitulum
b. Humerus
___ 3. Coronoid fossa
c. Metacarpals
___ 4. Five palmar bones
d. Phalanges
___ 5. Fourteen bones in digits
e. Radius
___ 6. Intertubercular groove
f. Ulna
___ 7. Lunate
___ 8. Olecranon fossa
___ 9. Radial notch
___10. Radial tuberosity
___11. Trapezium
___12. Triquetrum
___13. Trochlea
___14. Trochlear notch
___15. Ulnar notch
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Part C
Identify the bones and features indicated in the radiographs (X rays) of figures
15.7, 15.8, and 15.9.
Figure 15.7 Identify the bones and features indicated on this radiograph of the
elbow.
7
Figure 15.8 Identify the bones and features indicated on this radiograph of the
shoulder.
Figure 15.9 Identify the bones indicated on this radiograph of the left hand.
8