Skeletal Remains Objective: To learn how to determine sex and ethnicity using skeletal remains

Function of Bones Protection Give _________ Muscle ___________ shape Store __________ Produce ___________ shape attachment minerals blood cells

Bone Marrow Red marrow: Found in ________bone Produces ___________ Yellow marrow: Found in the _________ Stores __________ spongy blood cells medullary cavity energy (fat)

The Human Skeleton

Appendicular skeleton Axial skeleton Skull, ribs, sternum, vertebrae, sacrum, coccyx Appendicular skeleton All other bones

Need help remembering the bones of the body?

Table Talk Why do babies have more bones in their bodies than adults? Is it true that once you break a bone you will most likely break that bone again.

Long Bones

Cartilage cells ________ Cartilage turns into _________ Bone Growth Cartilage cells ________ Cartilage turns into _________ Growth is complete when ______________ divide bone Occurs at the epiphyseal plate Epiphyseal cartilage divides to create more cartilage, while the diaphyseal cartilage is transformed into bone. This increases the length of the shaft. the epiphyseal line fuses

Ossification (AKA Bone Formation) cartilage When _______ is replaced by ________ E.x. skull sutures bone Osteocytes are bone cells

Age Estimation Use: _______ of long bones Length Growth must be complete _______ of cranial sutures _________ of osteons present Length Closure Number

Age Estimation (Continued) Wear and tear on the body _________ Fractures Illness

Age Estimates Clavicle = 25 yrs Tibia 16 or 17 in females 18 or 19 in males Teeth are most accurate in toddlers and teens (up to 21)

Fracture Repair

Fractures and Skeletal Remains Fractures aid an investigation by ____________ fractures to medical records Matching

Fractures

Bone Remodeling Osteoclasts Osteoblasts Occurs in response to Bone _______ cells Osteoblasts Occurs in response to __________ stress Fracture Results in ___________ bones breaking building Repeated Thicker/stronger

Osteoporosis Bone mass ___________ decreases Bones become _________ brittle Decreased bone mass = Bone is destroyed faster than it is being built Brittle bones = Less HGH is being made

Fact or Fiction?

Sex Determination

Nuchal Area

Male Skull vs Female Skull

Male vs Female Mandible

Browridges

Determine the Sex of Each Skull

Pelvic Bone Male vs Female

Male vs Female Pelvis A B http://imc02.hccs.edu/BiologyLabs/AP1/05Skeletal/05PelvicImages/Pelvic_Quiz/index.html

Example #1 Determine the sex of a skull with large browridges, a rough nuchal area and a slanted forehead.

Example #2 Determine the sex of a square pelvis with a wide short sacrum.

Example #3 Determine the sex of a skull with small browridges, a wide mandible and a wide chin

Example #4 Determine the sex of a skull with a narrow mandible, a pointed chin and an inion hook. The answer is not a she-male.

Question #5 Which features of the pelvis would you use to determine the sex of a pelvis?