The Skeletal System

Chapter 5 – Anatomy/PhysiologyNHS

Dr. Smith

Skeletal System

Division of Skeleton

• Axial skeleton – skull, spine, chest (80 bones)

• Appendicular skeleton - upper and lower extremities (126 bones)

SKULL

• 8 cranium bones, 14 face bones, 6 ear bones

• Sutures –immovable joints

• Fontanels – “soft spots”• Sinuses –

spaces/cavities inside skull– Paranasal – NOSE

Spine• Vertebrete- irregular shaped spine bonds

• Cervical 7, Thoracic 12, Lumbar 5, Sacrum-Coccyx 2

Thorax/Chest• Sternum – breastbone• 12 pairs of ribs – attach

to vertebra– 14 true ribs - upper

seven pairs attached by costal cartilage

– 10 False ribs - lowest 2 pairs not attached to sternum “floating”; next three pair are attached to 7th rib

Upper extremities

• Scapula – shoulder blade• Clavicle – collar bone• Sternoclavicle joint – clavicle/sternum• Humerous – upper long bone in arm• Radius/Ulna – forearm bones• 8 Carpals – wrist bones• 5 metacarpals – palm bones• 28 phalanges – finger bones

Hip and Pelvis• Large coxal bone• illium, ischium, and pubis grow together in

an adult

Lower Extremities

• Femur – long bone – upper leg• Patella – knee cap• Tibia/fibula – lower leg bones• 8 Tarsals – ankle bones• 5 metatarsals – sole bones• 28 phalanges – finger bones

Foot Arches• Medial Longitudinal Arch - Inside of foot• Lateral Longitudinal Arch - Outside of foot• Transverse (metatarsal) arch - extends on

the ball of the foot

Man/Woman Differences

• Male skeleton's larger

• Female’s pelvis supports childbirth - male’s pelvis is more narrow - female's pelvis angle is greater

Joints - ARTICULATIONS • Synarthrotic joint - no movement• Anphiarthrotic joint - slight movement• Diarthrotic - free movement

Diathrotic Joint• Allow for free

movement• All have a joint

capsule, cavity, and a layer of articulating cartilage over the ends of the two joining bones ( synovial membrane in joint capsule

• Ligaments - fibrous connective tissue - hold joint together

LAB #1 - Skeletal Lab

• Materials - microscope, bone slides• Procedure: Observe draw and label slides #1-4

in lab-book. BE SURE TO LABEL. Answer results questions in full ENGLISH sentences

• Results: SEE RESULTS HANDOUT

GROUND BONE

Developing Cartilage Bone

Developing Membrane Bone

Tendon-Bone Junction