1. Skeletal System & Bone Identification
Forensic Science 2

2. The Role of Skeleton Bones are the organs of the skeletal system
It provides support for the body
It protects certain body organs (heart, lungs, etc)
Bones also make blood cells for the body, this is called bone marrow
Bone also stores calcium
Bones also provide a place for your muscles to attach

3. Bones in the Skeleton There are 206 bones in the adult human body
Babies and children have a few more bones than adults
Bones have medical names, but also have common names

4. Some Bones in the Skeleton
Upper Body Bones
Cranium (skull)
Mandible (jaw)
Clavicle (collar bone)
Scapula (shoulder)
Sternum (breastbone)
Humorous
Ulna and radius
Ribs
Vertebrae (backbone)
Phalanges (fingers)
Lower Body Bones
Ilium, Sacrum, Ischium (pelvis)
Femur (thigh)
Patella (kneecap)
Fibula/Tibia (shins)
Tarsals (ankle)
Phalanges (toes

6. Bone Growth & Structure
Bones are made of cells (like all organs)
Bone-forming cells are called osteoblasts
As you grow your bone cells divide (using mitosis) to get longer and stronger
There are two types of bone tissue
Solid/Compact bone: hard and compact part of the bone
Spongy bone: empty space in bones, usually fond near the ends of the bone, stores calcium

7. Bone Growth & Structure
Types of bones:
Long bones: longer than they are wide
Short bones: generally cube-shaped
Flat bones: thin, flat and usually curved
Irregular bones: do not fit into any of the above categories

8. Bone Structure Other Types of Bone Tissue:
Ligaments: tough fibers that holds bone together, usually found at joints
Joints: where bones come together, hinge joints, ball and socket joints, fixed joints, pivot joints

9. Joints

10. Fractures Comminuted – the bone breaks into many parts
Compression – the bone is crushed
Depressed – the fracture is pressed inward
Impacted – the bone ends are forced into each other
Spiral –occurs when excessive twisting force is applied
Greenstick – incomplete break
Compound – the bone breaks through the skin

11. Fractures
Comminuted are more common in the aged, whose bones are brittle
Depressed are typical skull fractures
Impact are common with falls
Greenstick are common in children whose bones are more flexible

12. Evidence from Bones Age at death in children (harder with adults)
Sex can only be estimated in the adult skeleton (because of the pelvis)
Previous injuries
Sometimes chronic infections such as leprosy, syphilis and tuberculosis