Skeletal system lecture notes 10/20/2025

What is the skeletal system made up of?

Bones Joints and Supporting tissue

Osseous tissue

Bone tissue

What are the tissues that make up bone?

Osseous tissue Dense regular/irregular CT and bone marrow

Functions of the skeletal system

Mineral storage and Blood cell formation

Blood cell formation in red bone marrow

Hemopoiesis

Fat storage

Happens in yellow bone marrow

Periosteum

Membrane that surrounds bone

Diaphysis

Shaft of the bone

Epiphysis

Both ends of long bone

Articular cartilage

Lines the ends of bones in joints (a type of hyaline cartilage)

Hyaline cartilage

slippery and smooth cartilage

Marrow cavity

contains bone marrow

Endosteum

Thin membrane lining marrow cavity

Compact bone

Allows bone to resist strength

Spongy bone

Allows bone to resist forces from many different directions

Epiphyseal lines

Separates epiphyses from diaphysis

Epiphyseal plates

Found in bones of children that are still growing

65% of the ECM is?

Inorganic matrix (Calcium salts)

35% of the ECM is?

Organic matrix (collagen fibers)

What does the inorganic matrix do?

Makes bones hard

What does the organic matrix do?

Helps bones be flexible