the skeletal system Flashcards
long bones
- found in the limbs
- have a shaft known as a diaphysis
- two expanding ends known as epiphysis
eg femur, humerus, radius
(support, movement and red blood cell production)
short bones
small, light, strong, cube-shaped bones used for weight bearing
eg carpals and tarsals
(weight bearing, fine or small movements, sock absorption)
flat bones
flat, normally thin, slightly curved, large surface area, protect vital organs
eg scapula, sternum, cranium
(protection and attachment for muscles)
irregular bones
complex shapes and do not fit into long, short, or flat
eg vertebrae
(protection (of spinal chord) movement)
sesamoid bones
- usually found within a tendon
- smooth surface for tendon to slide over
eg patella
(reduce friction, protection)
axial skeleton
main core of your body
eg skull, sternum, ribs, spine
appendicular skeleton
your limbs
eg includes any bones attached to the axial skeleton
order of vertebral column (top to bottom)
cervical
thoracic
lumbar
sacral
coccyx
cervical
- top 7 vertebrae of the neck
- first two bones are known as the atlas and axis
- forms the pivot joint in the neck to allow to head to move freely
thoracic
- 12 vertebrae of the mid-spine
- bigger than the cervical
- attach ribs which protect heart and lungs
- attach muscles of the back
lumbar
- 5 largest vertebrae of the lower spine
- biggest of moveable vertebrae
- support weight of other vertebrae and attach the muscles of the lower back
- discs produce a concave appearance
sacral
- 5 fused vertebrae which forms the sacrum
- helps form the wall of the pelvis
- supports the weight of vertebrae
coccyx
- 4 fused vertebrae forms the coccyx
- has no function
main functions of the vertebral column
- protects spinal chord
- supports rib cage (thoracic)
- supports body weight (lumbar)
- offers attachment for muscles in the back
- intervertebral discs receive and distribute impact (reduce shock)
postural defects
neutral spine
kyphosis
scoliosis
neutral spine
refers to good posture
3 natural curves
when viewed from anterior it should be completely vertical
kyphosis
excessive outward curve of the spine (bends from front to back) of the thoracic region
gives a hunchback appearance
often caused by poor posture but can be by deformities of the vertebrae
scoliosis
abnormal curvature of the spine either to the left or right
most common in thoracic region
causes are unknown
process of bone growth (term)
ossification
osteoblasts
cells that bring calcium to the bone
osteoclasts
cells that remove excess calcium
what are the functions of the skeletal system
- support
- protection
- attachment for skeletal muscle
- source of blood cell production
- store of minerals
- leverage
- weight bearing
- reduction of friction across a joint
support (function)
your bones give you shape and provide the supporting framework for the soft tissue of your body
protection (function)
bones surround and protect vital organs. pelvis = reproductive organs. cranium = brain
attachment for skeletal muscle (function)
your skeleton provides a surface for muscle attachment, allowing you to move. tendons attach muscle to bone. muscles contact and pull on the bones
source of blood cell production (function)
blood vessels feed the centre of your bone and stored within is bone marrow. this continually produces red and white blood cells
store of minerals (function)
bones hold minerals such as calcium and phosphorus, essential for bone growth and health. these minerals are stored and released into blood stream as regulated
leverage (function)
the bones provide a lever system against which muscles can pull to create movement
weight bearing (function)
bones are strong to support your weight. large forces are applied to your body and your skeleton is strong to prevent injury