Unit 4: Skeletal System Part 1

Bones, joints, cartilage, ligaments, bone marrow

Parts of the skeletal system

Makes blood cells

Function of red bone marrow

Storage

Function of yellow bone marrow

Axial and appendicular

Division of the skeletal system

Axial skeleton

Skull, ribs, sternum, vertebral column (core)

Structure and protection

Function of axial skeleton

Appendicular skeleton

Limbs and girdles, hip and shoulder, arms and legs (appendages)

Movement and support

Function of appendicular skeleton

Support the body, Protection, Movement, Storage of minerals and fats, Blood cell formation

Functions of bones

Hematopoiesis

Blood cell formation

206

How many bones does the adult skeleton have?

300

How many bones does an infant have at birth?

-Brain grows faster than bone

-To fit through the birth canal

Why are there extra bones in the skull?

The extra bones fuse together

Why do adults have less bones than infants?

Compact bone

Homogeneous, smooth and solid type of bone

Long bones and covers all bones

Where are compact bones found?

Spongy bone

Small needle-like pieces of bone that are airy

Short bones, irregular bones, flat bones, and the ends of long bones

Where are spongy bones found

They are lighter

Why are most bones spongy?

Diaphysis

Shaft of a long bone, composed of compact bone

Epiphysis

Ends or heads of long bones, composed of mostly spongy bone

Epiphyseal Line

Where diaphysis and epiphysis meet in a long bone

Epiphyseal Line

In youth made of hyaline cartilage in a long bone

Epiphyseal Line

Where bones lengthen as we grow aka growth plate in long bones

Periosteum

Outside covering of the diaphysis in a long bone

Periosteum

Has fibrous connective tissue membrane in a bone

Sharpey’s fibers/Perforating fibers

Secures periosteum to underlying bone in a long bone

Arteries

Supplies bone cells with nutrients in a long bone

Articular Cartilage

Covers the external surface of the epiphysis in long bones

Articular Cartilage

Made of hyaline cartilage in long bones

Articular Cartilage

Decreases friction at joint surfaces in long bones

Medullary Cavity

Cavity of the shaft in a long bone

Medullary Cavity

Contains yellow marrow (mostly fat) in adults in long bones

Medullary Cavity

Contains red marrow (for blood cell formation) in infants in long bones

Red

Spongy bone of epiphysis of adults contains what type of bone marrow?

Calcium phosphate

What accounts for hardness in our bones?

Collagen

What accounts for flexibility, strength, and resiliency in our bones?

Bone markings

Sites of attachments for muscles, tendons, and ligaments

Bone markings

Forms joints

Bone markings

Passages for nerves and blood vessels

Projections and processes and depressions or cavities

Categories of bone markings

depressions or cavities

Bone markings that are indentations

Projections and processes

Bone markings that grow out from the bone surface

Osteon (Haversian System)

A unit of bone

Osteon (Haversian System)

Columns of bone within the bone to distribute weight

Central (Haversian) Canal

Opening in the center of an osteon

Central (Haversian) Canal

Carries blood vessels and nerves

Perforating (Volkman’s) Canal

Canal perpendicular to the central canal

Perforating (Volkman’s) Canal

Connects neighboring osteons

Perforating (Volkman’s) Canal

Carries blood vessels and nerves

Lucunae

arranged in concentric rings

Lucunae

cavities containing bone cells (osteocytes)

Lamellae

Matrix; composed of calcium phosphate and collagen

Lamellae

Rings around the central canal

Lamellae

Sites of lacunae

Canaliculi

Tiny canals in the bone

Canaliculi

Radiate from the central canal to lacunae

Canaliculi

Forms a transport system for osteocytes; cell to cell contact via cytoplasm projections

Canaliculi

Materials in the blood from central canal are passed through these cells further out in osteon

Calcium and phosphate

What 2 minerals are stored in bones?

Femur

What is the largest bone?

Malleus, Incus, Stapes (Stirup) aka ossicles

What is the smallest bones?