The Skeletal System

The Appendicular Skeleton  Limbs (appendages)  Pectoral girdle  Pelvic girdle

The Pectoral (Shoulder) Girdle  Composed of two bones  Clavicle – collarbone (articulates with the manubrium)  Scapula – shoulder blade  Where each upper limb articulates with the trunk  These bones allow the upper limb to have free movement

Bones of the Shoulder Girdle Figure 5.20a–b

Scapula Figure 6-22

Bones of the arm  The upper arm is formed by a single bone  Humerus: extends from the scapula to the elbow Proximal Distal

Bones of the arm  The forearm has two bones  Ulna: lies on the medial (pinky) side  Radius: lies on the lateral (thumb) side Figure 5.21c

Bones of the arm  The hand – composed of 27 bones  Carpals (8)– wrist  Metacarpals – palm  Phalanges – fingers Proximal Middle Distal  Pollex – thumb (only has proximal and distal Figure 5.22

Bones of the Pelvic Girdle  Hip bones  Composed of three pair of fused bones  Ilium  Ischium  Pubic bone  The total weight of the upper body rests on the pelvis  Protects several organs  Reproductive organs  Urinary bladder  Part of the large intestine

Pelvis Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings Figure 6-26(a)

Male VS. Female

Bones of the Leg  The thigh has one bone  Femur – thigh bone  Longest, heaviest, strongest bone  Distally articulates with the tibia at the knee

Bones of the Leg  The leg has two bones  Tibia: Large medial bone (shin bone)  Fibula: slender, does not participate in joint movement. Stabilizes the ankle Figure 5.24c

Bones of the Lower Limbs  The foot  Tarsus (7) – ankle  Metatarsals – sole  Phalanges – toes Proximal Middle Distal  Calcaneus – heel  Hallux – big toe Proximal Distal

Figure 6-30(b)