Anatomy- Into to Skeletal System

Components of the skeletal system

bones, joints, cartilage, ligaments

How many bones in the adult body?

206

Two divisions of the skeleton

axial and appendicular

Bones that are included in the axial skeleton

skull, facial bones, ribs, vertebrae

Bones that are included in the appendicular skeleton

arms, legs, joints

Two types of bone

compact and spongy

Type of bone that is dense, looks smooth and homogenous

compact

Type of bone that is small needle-like pieces of bone and a lot of open spaces

in between other bone

spongy

Classification of Bone by Shape:

longer than they are wide; have a shaft with heads at both ends; mostly compact bone

long bones

examples of long bones

most of arm and legs

Classification of Bone by Shape:

cube-shaped, mostly spongy bone

short bones

examples of short bones

wrists and ankles

Classification of Bone by Shape:

thin, flattened, usually curved; 2 thin layers of compact bone with a layer of spongy bone in between

flat bones

examples of flat bone

skull, ribs, sternum

Classification of Bone by Shape:

bones that don’t fit into any other category

irregular

Examples of irregular bones

hips and vertebrae

Bone cell that builds the bone

osteoblasts

Type of bone cell that breaks down bown

osteoclasts

mature bone cell, maintain mineral matrix

osteocytes

The middle part (shaft) of the bone

diaphysis

covers and protects the diaphysis; made of fibrous connective tissue

periosteum

ends of long bones, thin layers of compact bone with spongy in between

epiphysis

allows for growth of bones; when done growing, hardens and becomes bone

epiphyseal plate

produce white and red blood cells and platelets

red marrow

specifically only to store fat

yellow marrow

Who has yellow marrow?

only adults

Functions of the skeleton

support, protection, movement, storage, blood cell formation