Skeletal System Flashcards
list the 5 functions of the skeletal system
- protection
- support
- locomotion
- mineral storage (Ca and P)
- blood cell formation (in bone marrow)
what are the two subsections of the skeleton?
- axial skeleton
2. appendicular skeleton
what does the axial skeleton contain?
all bones along or attached to the median plane, including the skull, vertebrae, ribs, and sternum
what does the appendicular skeleton contain?
bones of the limbs
how many cervical vertebrae do all mammals have?
7
how many cervical vertebrae do birds have? are they all separate?
14, but they’re all fused together
why do birds have a larger sternum?
to support breast muscles
list and describe the 5 bone shapes
- long bones: longer than they are wide, found in limbs
- short bones: more cube-shaped, found in carpus and tarsus
- flat bones: flatter than other bones, found in skull, sternum, ribs, scapula
- irregular bones: don’t fit with other classifications, usually unpaired, ex. vertebrae
- sesamoid bones: resemble sesame seeds, found in the patella and digits
describe pneumatic bones
contain air spaces called sinuses, lighter than others, avian skeleton has more than mammalian because flight
list and describe the 5 types of vertebrae
- cervical: most cranial, all mammals have 7
- thoracic: attached to/joined with ribs
- lumbar: lower back
- sacral: joined with pelvis, fused together
- caudal: most caudal, make up the tail
list the 8 basic vertebrae structures
- vertebral body
- spinous process
- pair of transverse processes
- pair of lamina
- pedicle
- pair of articular processes
- vertebral foramen
- transverse foramen
describe the location of the vertebral body
on the ventral side of the vertebrae, contains intervertebral disk
describe the spinous process
projects dorsally off vertebrae
where do the transverse processes project?
laterally off the vertebrae
what do the paired lamina do?
connect spinous process to transverse processes
what does the pedicle connect?
transverse processes to the vertebral body
describe the location of the paired articular processes
sit on the pedicle, where one vertebrae joins with the next
describe what the vertebral foremen contains
site of the spinal cord
describe the transverse foramen
holes in pedicle of cervical vertebrae, where blood vessels and nerves run through neck
where are transverse foramen found?
ONLY in cervical vertebrae!!
list the 3 types if bone cells
- osteoblasts
- osteoclasts
- osteocytes
give the function of osteoblasts
ossification, secrete hydroxyapatite, the mineral component of bone that makes bone hard
what is ossification?
formation of bone by osteoblasts
where are osteoblasts found?
found on the outside/lining bone surfaces so they can secrete bone on top of existing bone
describe osteocytes
mature bone cells, form when osteoblasts are surrounded by bone and become osteocyctes
describe the function of osteoclasts
resorption (breakdown of bone)
give the 6 structures specific to long bones
1, epiphysis
- diaphysis
- metaphysis
- epiphyseal plate
- epiphyseal line
- medullary cavity
describe the epiphysis
either end of a long bone (proximal epiphysis on top, distal epiphysis on bottom)
describe the diaphysis
the long shaft of a long bone
describe the metaphysis
connects epiphysis to diaphysis (proximal and distal end)
describe the epiphyseal plate and give the location
found in the meatphysis, is a layer of hyaline cartilage where growth of long bone occurs
describe the epiphyseal line
replaces epiphyseal plate when growth ceases, made up of compact bone
describe the medullary cavity
in center of diaphysis, does not contain bone, but bone marrow, and is hollow
describe red bone marrow
found in young animals, blood cell formation site
describe yellow bone marrow
found in adults, made of adipose (fat) tissue
list 3 structures found in all bones
- articular cartilage
- periosteum
- endosteum
describe articular cartilage
thin layer of hyaline cartilage that covers surfaces of a bone within a joint
describe the periosteum
covers the rest of the bone, 2 layers
list and describe the 2 layers of the periosteum
- superficial/outermost layer: dense irregular connective tissue, provides protection
- deep/inner layer: single layer of osteoblasts
describe the endosteum
lines internal surfaces of bone, thin layer of osteoblasts AND osteoclasts
list the 2 classifications when bone is classified by amount of extracellular matrix to amount of space
- spongy (cancellous) bone
2. compact bone
describe spongy bone
more space is found around matrix, made up of trabeculae, spaces between trabeculae contain red bone marrow and blood vessels, even as animal ages
what are trabeculae?
interconnecting rods of bone
describe compact bone
less space is found around matrix, more dense, found on the outside and is tougher, arranged in osteons
what are osteons?
the basic unit of compact bone, also called Haversian systems