The Skeletal System

Functions

Framework for the human body

Produces blood cells

Provides protection for organs

Helps us to breath

Acts as a warehouse for mineral storage

Allows for movement

Bones

Are Primary components of skeleton

Composed of non-loving mineral ( calcium and phosphorus

Alive

Greek meaning- "dried up body"

Long Bones: longer than they are wide

Arms and Legs

Short bones: fairly equal in width and length

Wrists and ankles

Flat bones: thinner and can either be flat or curved

skull, ribs, and sternum

Irregular bones: like a jigsaw puzzle, odd in shape

hip bone ans vertebrae

Periosteum

Tough and fibrous connective tissue covering bone

contains blood vessel which transport blood and nutrients to nurture bone cells

contains lymph vessels and nerves

Acts as anchor point for ligaments and tendons

Epiphysis: formed by increase in size of both ends of long bone

Diaphysis: region running between two epiphysis

Bone marrow

Yellow marrow: has high fat context; can convert to red marrow in an emergency

Red marrow: produces red blood cells

compact bone

Dense, hard tissue that composes shafts of long bones and forms outer layer of other bone types

under a microscope you can see tightly packed material

material forms microscopic, cylindrical shaped units called osteons

Spongy bone

arrangement of bars and plates called trabecula

irregular holes between trabecula make bone lighter in weight

holes give bone spongy appearance

Ossification: describes formation of bone in body

osteoprogenitor cell: non-specialized stem cells found in peritoneum

osteoblasts: cells that actually form bones

osteoclasts: believed to originate from type of white blood cell

osteocytes: considered mature bone cells that started as osteoblasts

Bone development begins when we are embryos through instramembranous and endochondral ossification

process starts at 8 weeks after conception when bone begins to replace cartilage

intramembranous ossification occurs when bone develops between two sheets composed of fibrous connective tissue

such as the development of your skull

cells from connective tissue turn into osteoblasts

movement

flexion: bending a joint

extension: straightening

plantar flexion: pointing toes downward

dorsiflexion: bending foot upward

abduction: moving away from midline

adduction: moving toward midline

inversion: turning foot inward

eversion: turning outward

circumduction: circular arm movement

gout: metabolic disorder where uric acid crystals deposit in connective tissue and synovial fluid

Rheumatoid arthritis: autoimmune disease affecting joints