Module 3B: Axial Skeleton Flashcards
how many bones are there in the human skeleton?
206
how many bones are there in the human body at birth?
approximately 300
what does the axial skeleton form?
a longitudinal axis of the body
what does the axial skeleton support?
the head, neck and trunk
what does the axial skeleton protect?
the brain, spinal cord and thoracic organs (like the heart and lungs)
the bones of our skull form the framework of what?
our face
the bones of our skull contain cavities for?
special sense organs (taste, smell, sight)
the bones of our skull provide openings for?
air and food passage
the bones of our skull anchor muscles for?
facial expression, which we use to show our feelings
the bones of the skull are divided into what two groups?
- cranium bones (top of skull)
- facial bones
what are our cranium bones?
- frontal
- occipital
- sphenoid
- ethmoid
- 2 parietal
- 2 temporal
what are our facial bones?
- mandible
- vomer
- 2 maxilla
- 2 zygomatic
- 2 nasal
- 2 lacrimal
- 2 palatine
- 2 inferior nasal concha
how many bones are there is the skull?
22 bones
where is the frontal bone?
the forehead
where is the parietal bones?
two sides of the top of our head back from the forehead
where is the temporal bones?
inferior to the parietal bone. right where our temples are
where is our nasal bone?
top part of our nose (front, center of skull)
where is our sphenoid bone?
back of boney orbit where our eyes go
- more on the lateral aspects of skull
- it is ONE bone
where is our zygomatic bones?
our cheekbones
where is our maxilla bones?
forms side of our nose, upper jaw where our top teeth attach
where is our vomer?
divides the nasal cavity into two
where is our mandible?
our lower jaw
what bone is the only moveable bone in our skull?
the mandible
can we move suture joints?
no
where is our ethmoid bone?
behind our lacrimal which is behind the upper part of our maxilla
where is our lacrimal bone?
behind the top portion of the maxilla
where is our inferior nasal conchas?
on the lateral side of our nose socket
what is the zygomatic process?
a zygomatic arch formed by the temporal bone and the zygomatic bone joining together
where is the mastoid process?
the lump immediately behind your ear when you push an earring backwards
where is the occipital bone?
the inferior posterior part of the skull
- the low back part of the skull
what attaches to the mastoid process?
a lot of muscles from the neck and back
why do suture joints join bones together in a zigzag pattern?
to cover more surface area to make very strong joints
- straight joints would not be as strong because they wouldn’t cover as much surface area
what is the coronal suture?
the joint that divides the frontal bone from the two parietal bones
what is the squamous suture?
divides the temporal bone from the parietal bone on the left and right sides of the skull
what is the lambdoid suture?
divides the two parietal bones from the occipital bone
what is the sagittal suture?
runs directly along the top of the skull dividing the two parietal bones
which sutures do not fully close until you are about one and a half years old?
the coronal and sagittal sutures
what is the external occipital protuberance?
the big bump on the back of the head
what is the superior nuchal line?
important for muscular attachment
- on the left and right sides slightly up from the external occipital protuberance
what is the inferior nuchal line?
important for muscular attachment
- on the left and right sides slightly down from the external occipital protuberance
what is the hard palate of the skull important for?
the oral cavity
the hole in the occipital bone from an inferior view is called?
the foramen magnum
where is the palatine bone?
posterior (behind) the maxilla and anterior (in front) the vomer and inferior nasal concha
what is the opening where the spinal cord exits the skull?
the foramen magnum