skeletal system

describe the anatomy and physiology of the skeletal system

3 main functions of the skeletal system

• movement

• protection

• storage of minerals and fat

what does osteoporosis cause

brittle and fragile bones

osteoarthritis

degenerative joint disease

4 major types of bones

• long

• short

• flat

• irregular

long bones appearance

longer lengths than widths

what do long bones make up most of

bones in the arms and legs

6 examples of a long bone

• femur

• humerus

• ulna

• radius

• tibia

• fibula

what is the marrow in a long bone called

yellow marrow

what does yellow marrow store

lipids (fat)

where could red bone marrow be found

at the ends of long bones

what is red bone marrow useful for

blood cell production

what do the ends of long bones have

growth plates

what happens to bones in growth plates

bone lengthens if it is growing

short bone appearance

same lengh and width

2 examples of short bones

square bones of the wrist and ankle

flat bones appearance

thin and flat

what are flat bones used to protect

vital organs

example of flat bones

ribs

what do flat bones contain

red bone marrow

what do flat bones produce

blood cells

2 examples of irregular bones

hip bones and vertebrae

joints

places where bones meet other bones

what are joints that are movable called

ball-and-socket joints

2 examples of the ball-and-socket joints

hips and shoulders

example of immovable joints

joints in the skull

ligaments

bones are attached to other bones

what does the hyoid bone support

the tongue

what is the only bone in the body that is not connected to other bones

hyoid bone

what 2 muscles is the hyoid bone held in place by

suprahyoid and infrahyoid muscles

what do hyaline cartilages cover

the articulating surfaces of bones

what does the hyaline cartilage prevent

prevents joints from grinding against each other

what do synovial joints contain

lubricating synovial fuid

are synovial joints capable or incapable of movement

capable of movement

3 types of synovial joints

• pivot

• ball-and-socket

• hinge

where is bone synthesized

in tubular structures called osteons

what is the functional unit of compact (dense) bone

osteons

what are osteons composed of

calcium and phosphate-rich hydroxyapatite embedded in a collagen matrix

what are osteons also called

haversian systems

2 main functions of osteocytes

maintain bone and are able to sense physical stresses

what do lacunae contain

osteocytes

how do lacunae connect to each other

within an osteon through canaliculi

what is the bone covered by

periosteum

what does the periosteum contain

nerves and blood vessels

2 main types of bone cells

multinucleate osteoclasts and mononucleate osteoblasts

what do osteoblasts replace and secrete

replace cartilage and secrete mineral deposits that form the matrix

matrix

nonliving substance of the bone

what do osteoblasts develop into

osteocytes

2 main functions of osteocytes

strengthen bone tissue and carry out metabolic functions

main function of osteoclasts

remove bone

what happens if osteoclasts break down bone faster than osteoblasts deposit minerals

bones become weak and brittle, causing osteoporosis

main function of osteoblasts

deposit minerals

what does arthritis damage

the cartilage that articulates between jonts

what causes brittle bone disease (osteogenesis imperfecta)

genetic defect in the collagen matrix

what does brittle bone disease cause bones to do

break easily

what are skeletal muscles attached to

bones

what is the purpose of the connection of skeletal muscles to bones

to communicate with the central nervous system

what happens when the muscle receives a signal to contract from the central nervous system

the muscle contracts, moving the bone to which it is connected

what do muscles connect to

bones with tendons

what are bones with tendons made up of

connective tissue

what is the contracting muscle called

prime mover

what is the relaxed muscle called

antagonist

as one pair of muscles relaxes, the other _______ for one type of movement

contracts