The Mammalian Skeleton Upper Sixth Biology

Aims To recognise and name the major bones of the mammalian skeleton To understand the subdivisions of the skeleton To understand that the structure of the thoracic and lumbar vertebrae relate to their function

The major bones of the human skeleton On your hand out, label as many of the bones as you can

Skeleton Basics Humans have an endoskeleton Non vertebrates have a tough outer covering the exoskeleton Endoskeletons are less protective But allow greater growth Made of bone (ossification) Cartilage in some parts (ends of joints and at the ribs)

Subdivisions of the skeleton Two main divisions The axial Skeleton Skull, vertebral column, ribs and sternum The appendicular skeleton Limb, pectoral and pelvic girdles

The axial skeleton Neck and head-cervical Chest and ribs-thoracic << < > The axial skeleton Neck and head-cervical Chest and ribs-thoracic Lumbar-Lower back Sacrum-fused-hip bones Coccyx-4 fused

Lumbar vertebra

Lumbar vertebrae Label your diagram Draw up a table showing the names and functions of each part of these vertebrae Also list the adaptations that make these functions possible

Thoracic Vertebrae The ribs articulate at the ends of the transverse process and also at a point just above the centrum Neural spins are longer and slope downwards

Intervertebral joints Joined together by ligaments Discs of cartilage act as shock absorbers Spinal nerves and blood vessels exit between gaps

The pentadactyl limb Comes from the term ‘Five fingered’ Basic structure founds in many animals Size of bones may vary, but basic structure is the same Arms and legs are fundamentally the ‘same’

Pentadactyl Limb Draw a table, comparing the bones in the appendicular skeleton

Summary You should now be able to To recognise and name the major bones of the mammalian skeleton To understand the subdivisions of the skeleton To understand that the structure of the thoracic and lumbar vertebrae relate to their function