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Lateral view of skull

A view of the lateral skull is dominated by the large, rounded brain case above and the upper and lower jaws with their teeth below ( [link] ). Separating these areas is the bridge of bone called the zygomatic arch. The zygomatic arch    is the bony arch on the side of skull that spans from the area of the cheek to just above the ear canal. It is formed by the junction of two bony processes: a short anterior component, the temporal process of the zygomatic bone    (the cheekbone) and a longer posterior portion, the zygomatic process of the temporal bone    , extending forward from the temporal bone. Thus the temporal process (anteriorly) and the zygomatic process (posteriorly) join together, like the two ends of a drawbridge, to form the zygomatic arch. One of the major muscles that pulls the mandible upward during biting and chewing arises from the zygomatic arch.

On the lateral side of the brain case, above the level of the zygomatic arch, is a shallow space called the temporal fossa    . Below the level of the zygomatic arch and deep to the vertical portion of the mandible is another space called the infratemporal fossa    . Both the temporal fossa and infratemporal fossa contain muscles that act on the mandible during chewing.

Lateral view of skull

This image shows the lateral view of the human skull and identifies the major parts.
The lateral skull shows the large rounded brain case, zygomatic arch, and the upper and lower jaws. The zygomatic arch is formed jointly by the zygomatic process of the temporal bone and the temporal process of the zygomatic bone. The shallow space above the zygomatic arch is the temporal fossa. The space inferior to the zygomatic arch and deep to the posterior mandible is the infratemporal fossa.

Bones of the brain case

The brain case contains and protects the brain. The interior space that is almost completely occupied by the brain is called the cranial cavity    . This cavity is bounded superiorly by the rounded top of the skull, which is called the calvaria    (skullcap), and the lateral and posterior sides of the skull. The bones that form the top and sides of the brain case are usually referred to as the “flat” bones of the skull.

The floor of the brain case is referred to as the base of the skull. This is a complex area that varies in depth and has numerous openings for the passage of cranial nerves, blood vessels, and the spinal cord. Inside the skull, the base is subdivided into three large spaces, called the anterior cranial fossa    , middle cranial fossa    , and posterior cranial fossa    (fossa = “trench or ditch”) ( [link] ). From anterior to posterior, the fossae increase in depth. The shape and depth of each fossa corresponds to the shape and size of the brain region that each houses. The boundaries and openings of the cranial fossae (singular = fossa) will be described in a later section.

Cranial fossae

This figure shows the structure of the cranial fossae. The top panel shows the superior view and the bottom panel shows the lateral view. In both panels, the major parts are labeled.
The bones of the brain case surround and protect the brain, which occupies the cranial cavity. The base of the brain case, which forms the floor of cranial cavity, is subdivided into the shallow anterior cranial fossa, the middle cranial fossa, and the deep posterior cranial fossa.

Questions & Answers

where is heart located
medical Reply
thoracic cavity
Ashley
1
Noor
between which line
medical
where is the thorax located at?
angel
heart located between T5-T8
Biplav
thorax is the area between the base of neck to the diaphragm
Biplav
The heart is placed Obliquely behind the body of the sternum and adjoining part of the costal cartilages, so that 1/3 of its lies to the right and 2/3 to the left of the median plane
Manisha
The heart lies in the thoracic cavity in the mediastinum (the space between the lungs) . It lies obliquely, a little more to the left than the right. Presents the base above and the apex below. The apex is 9cm to the left of the midline at the level of the 5th intercostal space
Bashraba
why does a person's complexion change when he relocates to another cold environment & tends to become more light skinned, does this mean the distribution of melanin to the surface of the skin changes ?
Ferrel Reply
what is Aponeurosis
Komolika Reply
aponerosis is modifications of deep fascia of the skin.. it generally covers the muscles Or tendons within it
niyati
A sheet of parly white fibrous tissue that takes the place of tendon in flat muscles having a wide area of attachment
mishra
what is the difference between sex and gender?
Hridya Reply
Those are synonyms
Ferrel
What is Physiology?
Nancy Reply
The study of functions of the human body.
Evans
study of human body
obaidullah
The biochemical study of any organism (eg. different systems) is called Physiology.
Doctor
which category of bone is among the most numerous in the skeleton?
DAMSON Reply
what is a nutrition ?
Jitu Reply
Nutrition is the process of providing or obtaining the food necessary for health and growth.
Gloria
Nutrition is the process of taking food and using it for growth , repair and metabolism ...
Om
how many parts of bone
Amir Reply
know the meaning of both messages
Amir
what is the name of suture that is present between frontal. parietal. occipetal ...
Amir
what is the name of suture that is present between frontal. parietal. occipetal ...
Amir
Coronal suture present between frontal and parietal bone and lambdoid suture present between parietal and occipital bone ...
Om
Squamous suture
Ferrel
& where is the squamous suture ?
Ferrel
what is meant by synovial joint? and what is this role
Fozia
type of joint that is found between bones that move against each other. it's function is to prevent bone friction
Ferrel
epinephrine is the true meaning of epi
Michele Reply
what does the word 'epi' means
Melex Reply
good evening, my question is what are function of metal in human body like aluminum?
Yosef Reply
please want you to help me in understanding digestive system
Hamidu Reply
this is muscular system?
Patel Reply
bruh moment
Viana
It is an organ system consisting of skeletal ,smooth and cardiac muscles
mishra
im too retarded to be here
Viana
naww Viana, I know it's hard to absorb info, I'm having the same issue, but keep practising, chin up.
Katarina
what is the question
Amir
to have a better understanding as to how our human bodies function. the knowledge we gain can improve our quality of life. Without our study of anatomy how could a doctor know what prescription to give us when our bodies is being attacked by a bacteria? We wouldn't!
Robin Reply
discuss nervers system in human being life.
Allen Reply
neuralgia what is other name of it
Muniba

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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