functions of the vertebral column
- supports the head and bears weight of the body while allowing movement of head and trunk
- protects the brain
- site for muscle attachment
- protects the spinal cord
individual vertebrae are named using
a letter and a number
vertebrae are bound into a column by …
ligaments and intervertebral discs
intervertebral discs
cushion like pads found between vertebrae
layers of intervertebral discs
inner-gelatinous mass
middle- fibrocartilage
superficial layer- collagen fibers
the inner gelatinous mass of intervertebral discs makes the disc _____ and ____
elastic and compressible
function of the collar
it limits the expansion of the gelatinous mass when the spine is compressed and withstands twisting forces
function of intervertebral discs
act as a shock absorber and allow the column to flex and extend to a lesser extent bend laterally
the size of the vertebral bodies ______ as you go down
increases
why does the increase of vertebral bodies happen as you go down?
this increase in size occurs because an inferior vertebrae must support more weight than the one superior to it
-this trend ends at the sacrum because the bodys weight is transferred to the pelvis
what do the vertebral column curves do?
facilitate upright posture
- add strength to the vertebral column
- absorb shock
early in development how many curves does the spine have? and is it convex or concave
1: convex posteriorly
what are the primary curves?
thoracic and sacral curves
-because their direction does not change with age
what are the secondary curves?
cervical and lumbar curves
-because they change over time to be concave posteriorly
when does the change in the cervical curve occur?
-begins late intrauterine life and becomes prevalent when a child holds up his/her head and sits upright
when does the lumbar curve change?
when a child starts to walk
what is the most flexible portion of the vertebral column?
cervical region
why is the thoracic region not very flexible?
because the thoracic vertebrae are parts of the thoracic cage
what movements does the lumbar region allow?
allows bending movements and some twisting motions
what are the least flexible portions of the vertebral column?
the sacral and coccygeal regions
what does the thoracic cage do?
protects the viscera of the thorax and provides muscle attachment sites
-the cage is flexible enough to allow the movements that are necessary for respiration
what do the clavicles, scapulas, and coxal bones have in common?
the provide muscle attachment sites
what binds vertebrae together?
ligaments and intervertebral discs
where are breasts found and what does it consist of?
found in the hypodermis
- consists of adipose and other connective tissues, blood vessels, lymph vessels, nerves, glandular tissue (mammary gland)
- lactation
mammary gland
specialized sweat glands that produce and secrete milk that is used to nourish a newborn
there is a muscle called the erector spinae. this name tells you the muscles ______.
function
motor neurons are located within the
ventral horns
which segments of the vertebral column have lateral horns as well as dorsal and ventral horns?
thoracic and superior lumbar segments (T2-L1)
function of the sternum
- protects thoracic viscera
- muscle attachment
costal cartilages
- paired
- made of hyaline cartilage
- contribute to mobility and elasticity of the walls of the thoracic cage
- muscle attachment site
ribs
12 pairs
- articulate with vertebral column
- protect thoracic viscera
- some articulate with sternum via costal cartilage
- muscle attachment
true ribs
- first 7 pairs
- articulate with sternum via costal cartilage
false ribs
- last 5 pairs
- 8, 9, 10 attach indirectly to sternum
- 11, 12 do not attach to sternum
floating ribs
11 and 12 ribs
the floating ribs are false ribs?
yes
vertebral column
24 nonfused
- 9 fused
- divided into 5 types
cervical vertebrae
- nonfused
- 7 of them
thoracic vertebrae
- nonfused
- 12 of them
lumbar vertebrae
- nonfused
- 5 of them
sacral vertebrae
fuse to form sacrum
5 of them
coccygeal vertebrae
- fuse to form coccyx
- inferior to sacral vertebrae
- 3-5 in number
vertebral canal
passageway for the spinal cord and dorsal and ventral roots of spinal nerves
intervertebral foramina
passageway for spinal nerves
clavicle
- paired
- muscles attachment
scapula
- paired
- muscle attachment
coxal bone
paired
-muscle attachment
pelvis
composed of sacrum and coccyx
- protects pelvic viscera
- bears weight
costal facets are only found on
thoracic vertebrae
superior articular facets of thoracic vertebra face in which direction
posteriorly
inferior articular facets of thoracic vertebrae face in which direction
anteriorly
vertebral arch of lumbar vertebrae function
SOME protect the spinal cord
superior articular facets of lumbar vertebrae usually face in which direction
medially
inferior articular facets of lumbar vertebrae usually face in which direction
laterally
transverse foramina are only on what vertebrae?
cervical vertebrae
what bone marking is found on all thoracic vertebrae but not on other vertebral types?
costal facets
to distinguish a lumbar vertebra, you look to see if the vertebra does not have ______ or ______.
transverse foramina or costal facets
tubercles are not found on which ribs?
11th and 12th
coxal bone
- paired
- articulates with the other coxal bone anteriorly; articulates with the sacrum posteriorly
- muscle attachment
of articulations T1-9 makes
12
of articulations T11-12 makes
8
of articulations T10 makes
10
of articulations L1-5 makes
6
of articulations C1 makes
5
of articulations C2 makes
6
of articulations C3-7 makes
6
what separates the thoracic and abdominopelvic cavities?
diaphragm
the central tendon is composed of
dense connective tissue
