SKELETAL SYSTEM:


BONES:

 

Cranium: top of skull

 

Mandible: jaw bone

 

Vertebrae: back bones

 

Clavicle: collar bone

 

Scapula: shoulder blade

 

Sternum: center of chest

 

Rib: self-explanatory

 

Pelvis: hip bone

 

Humerus: top of arm

 

Radius: thumb side of forearm

 

Ulna: outside of forearm

 

Femur: top of leg

 

Tibia: larger bone in lower leg

 

Fibula: smaller bone in lower leg

 

Patella: kneecap

 

Phalanges: fingers and toes


 

GENERAL:

 

Skeleton: All of the bones in an organism. Provides structure, support and protection.

 

Internal skeleton: located inside of body. Ex.: humans, vertebrates

 

External skeleton: also known as exoskeleton. Hard outer covering that provides structure, support, protection. Ex.: insects, lobsters

 

Joint: Area where two bones meet. Most provide for movement; include fluid for lubrication and cartilage for protection. Ligaments hold bones together.

 

Cartilage: smooth, slippery substance. Provides cushion, protection for bones in joints; prevents the bones from wearing against each other. Provides some structure in nose and ear. Provides flexibility in ribcage.

 

Ligament: strong connective tissue fibers that hold bones together

 

Tendon: strong connective tissue fibers that hold muscle to bone

 

Fluid: thick, slippery liquid that provides lubrication in joints

 

Skeletal system: all of the bones in the body, together with the ligaments and cartilage

 

Outer covering: thin, tough, smooth layer around outside of bone. Provides protection and attachment point for muscles

 

Compact bone: solid, dense layer around outer surfaces of bones

 

Spongy bone: highly porous regions of bone inside layer of compact bone; observed in ends of long bones (femur, etc.) and inside flat bones, like ribs. Holes are filled with fat cells, marrow, etc. Spongy bone is porous, but not squishy like a sponge!

 

Marrow: squishy, fatty tissue found in centers of long bones. Primary site of blood cell production

 

Rickets: Bone disease resulting in weak or misshapen bones. Caused by vitamin D deficiency insufficient exposure to sunlight.