Skeletal System Functions PDF

**PHED REVIEWER** **FUNCTIONS OF SKELETAL SYSTEM** **1. Movement** Skeletal system provides points of attachment for muscles. Your legs and arms move when the muscles pull on the bones. **2. Support** The **backbone** is the main support center for the upper body. It holds your head up and prot...

**PHED REVIEWER** **FUNCTIONS OF SKELETAL SYSTEM** **1. Movement** Skeletal system provides points of attachment for muscles. Your legs and arms move when the muscles pull on the bones. **2. Support** The **backbone** is the main support center for the upper body. It holds your head up and protects your spinal cord. **3. Protection** The bones of your **skull** protect your brain. Your **ribs** protect your lungs and heart from injury. **4. Makes Blood** Red and white blood cells are formed by tissue called **marrow**, which is in the center of the bone. **5. Storage** Bones store minerals, such as calcium and phosphorus, for use by the body. **TWO MAJOR PARTS OF SKELETAL SYSTEM** **1. Axial Skeleton** Central core of the body. It includes the skull, spine, ribs and sternum. **2. Appendicular Skeleton** Comprised of upper and lower extremities. It includes shoulder girdle, Arms, Legs and Pelvis. **FOUR BASIC BONE SHAPES** 1\. **Long** - Arms, Legs, Fingers 2\. **Short** - Wrist and Ankles 3\. **Flat** - Skull and Sternum 4\. **Irregular** - Spine **BONE STRUCTURE (4 LAYERS)** **1. Periosteum** Covers bones. **2. Compact Bone** Lies beneath the periosteum. **3. Spongy Bone** Lies beneath the Compact Bone. **4. Bone Marrow** Fills the gaps between the spongy bone. **CRANIAL BONES** **MANDIBLE AND MAXILLA** **Clavicle (Collar Bone)** Holds the shoulder joint away from the rest of the upper body. Its thickness is 11mm to 15mm. **Scapula** Located on the back side of the ribcage and helps provide part of the shoulder joint and movement for the arms. **Spinal Cord (Vertebral Column)** 1\. **Cervical Region (C1 -- C7)** The neck bones it consists of 7 vertebrae bones. 2\. **Thoracic Region (T1 -- T 12)** Where the ribs attach to it consists of 12 vertebrae bones. 3\. **Lumbar Region (L1 -- L5)** The lower part of the back it consists of 5 bones.  **Sacrum** A shield-shaped bony structure that is located at the base of the lumbar vertebrae and that is connected to the pelvis. **Coccyx** A small triangular bone at the base of the spinal column in humans and some apes. **Humerus (Upper Arm Bone)**  **Radius and Ulna** **Carpal (Wrist Bones)** **Metacarpals (Metacarpus)**  **Phalanges (Finger Bones)** **Sternum (Breastbone)** Is a partially T shaped vertical bone that forms the anterior portion of the chest wall centrally. **Pelvis (Dancing Bones)** A basin-shaped structure that supports the spinal column and protects the abdominal organs. **Femur (Thigh Bone)** It\'s the longest and strongest bone in your body. **Tibia and Fibula** Are the two long bones located in the lower leg. The **tibia** is a larger bone on the inside, and the **fibula** is a smaller bone on the outside.  **Tarsals** Consist of seven short bones located at the proximal region of the foot. They are arranged in proximal and distal rows. **Metatarsals** Refer to the five long bones found in each foot. They are numbered I to V, from medial to lateral. **Phalanges** Are the bones that make up the fingers of the hand and the toes of the foot. **Calcaneus (Heel Bone)** Is a large and strong bone that forms the back of the foot and transfers most of the body weight from the lower extremity to the ground.