bone tissue and the skeletal system

skeletal system components

bone and cartilage

functions of the skeletal system

supports body, facilitates movement, protects internal organs, produces blood cells, stores and releases minerals and fat

bone marrow

soft connective tissue that fills the interior of bone

types: yellow and red

yellow bone marrow

adipose tissue with adipocytes used for energy

red bone marrow

production of blood cells (hematopoiesis) occurs here

shape classifications of bones

long, short, flat, irregular, sesamoid

long bones

type of bone that is cylinder-shaped and longer than it is wide

used for leverage

short bones

type of bone that is cube-like shaped which is equal in length, width, and thickness

used for stability and support while allowing for motion

flat bones

type of bone that is thin and curved

used as attachment points for muscles and protects internal organs

irregular bones

a type of bone that has a complex shape used for protecting internal organs

sesamoid bones

a type of bone that is small, round and embedded with tendons

diaphysis

the shaft of a bone that contains a medullary cavity filled with yellow marrow

epiphysis

wide sections at the end of the bone filled with spongy bone and red marrow

periosteum

fibrous membrane that covers the outer surface of the bone

where tendons and ligaments attach to bones

metaphysis

a layer of hyaline cartilage where the diaphysis and epiphysis meet

contains the epiphyseal plate where bone growth occurs

endosteum

within the medullary cavity where bone growth, repair, and remodeling occur

articular carilage

thin layer of cartilage at the end of the epiphysis

reduces friction, absorbs shock, and easier joint movements

osteoblasts

bone cells in the periosteum and endosteum that forms the bone matrix

they form new bones and add growth to existing bone tissue

osteoclasts

resorbs or breaks down old or damaged bone to be replaced

osteocytes

primary mature bone cells

osteogenic cells

stem bone cells that can differentiate into osteoblasts

types of bone tissue

compact and spongy bone

compact bone

dense form of bone tissue able to withstand forces

osteon

cylindrical unit of compact bone

interstitial lamellae

bone matrix the fill the space between osteons

central canal

space in the middle of osteons where blood vessels, nerves, and lymphatic vessels pass through bone

spongy bone

type of bone tissue found between compact bone that is not densely packed

contains red marrow

trabeculae

units of spongy bone

ossification

process of bone development

interstitial growth

the process of bones growing in length at the epiphyseal plate

makes diaphysis longer and pushes epiphyses further from one another

appositional growth

the process of bones growing in diameter by the production of new bone tissue underneath the periosteum

hypocalcemia

LOW blood calcium levels

fixed by osteoclasts breaking down bone matrix to release calcium into bloods plasma

hypercalcemia

HIGH blood calcium

fixed by osteoblasts by pulling calcium from plasma and places it into osseous matrix

bone repair stages

fracture hematoma forms, internal and external calli form, cartilage of the calli is replaced by trabecular bone, remodeling occurs

tranvserve bone fracture

break that is straight across the long axis of the bone

oblique fracture

break in bone that is not straight across

spiral fracture

bone segments are pulled apart from a twisting motion

communited fracture

many breaks that result in small pieces of bone

impacted fracture

when a piece of bone is driven into the other from compression

greenstick fracture

partial fracture where only one side of the bone is broken

compound fracture

when one end of the broken bone tears through the skin

simple fracture

no skin tears from the bone fracture