<< Chapter < Page Chapter >> Page >

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

i thought a cell is the fuctional unit of an orgarnism.
mutesi Reply
Explain the major features and properties of the cell membrane
Robina Reply
contants ofa lipid bilayers w the enbedded proteins it is faction of the cell membaren
bariise
it is made up of protein,fat and a small portion of carbohydrates. it is semipermeable but impermeable to uncharged water molecules.
Chidiebere
Describe an experiment to verify the law of constant composition
Ssekamatte
thanks
Momoh
amazing the exprement is hard to set up can you please help us describe it for us?
Momoh
What are blood vessels of will's circle
Madu Reply
vertebral arteries and cerebral arteries
Chidiebere
What are sutures of cranial cavity ?
Madu Reply
there are four. the coronal, sagittal, squamous and lambhoidal sutured
Chidiebere
structure of a cell
Robina
pelvic cavity contents?
unimarwat Reply
ilium ,ischium ,pubis
Madu
but that is the three parts of the hip bone
Chidiebere
Describe the muscular skeletal system in terms of definition.. Skeleton Apendicular skeleton Axial skeleton Joints
Sherrine Reply
the basic framework of body made and cartilage is called skeleton skeleton which form limbs is called appendicular skeleton skeleton which form main axis of body is called axial skeleton the points at two or more bones meets is called joints
unimarwat
write short notes on ligaments,curves and moverment of vertebral column.
mutesi Reply
cranial nerves notes
unimarwat
what is the Analysis
ROHIT Reply
what is Anatomy
ROHIT Reply
it's a organs and bouns reading
AJITH
Cutting Up
Nonie
Cutting Up
Nonie
to dissect
Nonie
what usually cause blood pressurae
Abdullateef Reply
too much salt in the diet
Abuusu
older age
Abuusu
Even family history of high blood pressure
Abuusu
yes
Yaqub
too much salt in the diet
Yaqub
stress is the leading factor
Richard
smoking and too much alcohol consumption
Annu
obesity can also cause hypertension
Yaqub
high temperature of the body high salt of the body
Drs
how does the temperature affect the blood pressure?
Chidiebere
sex
Onavwie
What sex.?
Arshad
Male
Vikas
i mearnt gender,there's increased blood pressure in male than female
Onavwie
guys, read the question, involuntary pumping of heart causes the blood pressure in the arteries, he has not asked about high or low BP.
Jess
explain the cellular mechanism that produces tetanus and summation
Jenica Reply
epithelial cells polerity
jitendra Reply
tissues
Deepak
demonstrate the fluid replacement in the body
John Reply
the red blood cells is in the long bones or flat bones?
isbii
as age increases, the bone elongates .. will the joint vanish?
Sushruth Reply
what is anatomy?
Ivy Reply
structure
Allonda

Get the best Anatomy & Physiology course in your pocket!





Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Anatomy & Physiology' conversation and receive update notifications?

Ask