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Zygomatic bone

The zygomatic bone    is also known as the cheekbone. Each of the paired zygomatic bones forms much of the lateral wall of the orbit and the lateral-inferior margins of the anterior orbital opening (see [link] ). The short temporal process of the zygomatic bone projects posteriorly, where it forms the anterior portion of the zygomatic arch (see [link] ).

Nasal bone

The nasal bone    is one of two small bones that articulate (join) with each other to form the bony base (bridge) of the nose. They also support the cartilages that form the lateral walls of the nose (see [link] ). These are the bones that are damaged when the nose is broken.

Lacrimal bone

Each lacrimal bone    is a small, rectangular bone that forms the anterior, medial wall of the orbit (see [link] and [link] ). The anterior portion of the lacrimal bone forms a shallow depression called the lacrimal fossa    , and extending inferiorly from this is the nasolacrimal canal    . The lacrimal fluid (tears of the eye), which serves to maintain the moist surface of the eye, drains at the medial corner of the eye into the nasolacrimal canal. This duct then extends downward to open into the nasal cavity, behind the inferior nasal concha. In the nasal cavity, the lacrimal fluid normally drains posteriorly, but with an increased flow of tears due to crying or eye irritation, some fluid will also drain anteriorly, thus causing a runny nose.

Inferior nasal conchae

The right and left inferior nasal conchae form a curved bony plate that projects into the nasal cavity space from the lower lateral wall (see [link] ). The inferior concha is the largest of the nasal conchae and can easily be seen when looking into the anterior opening of the nasal cavity.

Vomer bone

The unpaired vomer bone, often referred to simply as the vomer, is triangular-shaped and forms the posterior-inferior part of the nasal septum (see [link] ). The vomer is best seen when looking from behind into the posterior openings of the nasal cavity (see [link] a ). In this view, the vomer is seen to form the entire height of the nasal septum. A much smaller portion of the vomer can also be seen when looking into the anterior opening of the nasal cavity.


The mandible    forms the lower jaw and is the only moveable bone of the skull. At the time of birth, the mandible consists of paired right and left bones, but these fuse together during the first year to form the single U-shaped mandible of the adult skull. Each side of the mandible consists of a horizontal body and posteriorly, a vertically oriented ramus of the mandible    (ramus = “branch”). The outside margin of the mandible, where the body and ramus come together is called the angle of the mandible    ( [link] ).

The ramus on each side of the mandible has two upward-going bony projections. The more anterior projection is the flattened coronoid process of the mandible    , which provides attachment for one of the biting muscles. The posterior projection is the condylar process of the mandible    , which is topped by the oval-shaped condyle    . The condyle of the mandible articulates (joins) with the mandibular fossa and articular tubercle of the temporal bone. Together these articulations form the temporomandibular joint, which allows for opening and closing of the mouth (see [link] ). The broad U-shaped curve located between the coronoid and condylar processes is the mandibular notch    .

Questions & Answers

There was this time when the teacher is explaining about something that involves calculating.When the teacher calculate that (2×4)-(1×-3)=11.I was confused and think that the answer is wrong, so I asked the teacher.Then,I realized I calculate wrongly and then my head feels hot. Why?
Dicky Reply
I mean... (2 x 4)- (1 x -3) = 11
But since I don't really care about it. My head slowly goes back to normal.
blood is unique it is the only flueid tissue in the body
this is fascinating
for real
what is blood
sujon Reply
lol. the red substance in your body. that circulates food nutrients and oxygen
Blood is composed of plasma and formed elements. The plasma is about 55% of blood and is about 80-90% water usually. The other 20-10% accounts for solutes such as ions, nutrients, gases, and hormones.
Blood is a fluid type of connective tissue and it's formed elements (cells) include RBC, WBC, and plalets.
what is sasamoid bone?
hafeez Reply
how many types of bone on the base of shape
i want join the conversation
juwar Reply
feel free to do so
where are you from ?
hi what's up
well hello
Im from kashmir,but I'm studying in punjab
I'm studying pharmacy at JUST University in jordan
so am i emad 😅
I am Javed Ali
hello i am hafeez from gilgit
explain the mechanism(release and control) of hormonal interplay for fluid and electrolyte.
Cassie Reply
There are three main ways in which hormones may be released. Humoral stimulus - occurs when their is an inbalance in electrolytes in the body. Neural stimulus - occurs when autonomic nerve fibers stimulate glands to release hormones.
Hormonal stimulus - occurs when a hormone causes another hormone to be released from another gland.
what are the main pumps found in the cell membrane
pauline Reply
sodium potassium pump
Differences between ligaments and catilage
joy Reply
differences between catilage and ligaments
Both are different types of connective tissues. Second difference is that cartilage contains chondroblasts rather than fibroblasts. Their is also slight differences on their extracrullar matrix. For ex, cartilages tend to contain more collagen than tendons and ligaments.
Both types of connective tissue also function differently. Ligaments connect bone to bone, while cartilage have a variety of function like cushioning bones and giving structural support like on the nose and ears.
explain the causes of the refractory period of a nerve fiber
Sophia Reply
Refractory period immediately following stimulation during which a nerve or muscle is unresponsive to further stimulation. Brief pause in stimulus or excitation.
To add on, the brief pause is produced because of the event of establishing a resting membrane potential that needs to be produced before depolarization (another action potential) can occur again.
The refractory period also gives a chance for neurotransmitters to be replenished on the axon terminal.
what is hypoxia
Akas Reply
I guess it's low supply the oxygen to the tissues
A condition in which tissues (especially the blood) are deprived of an adequate supply of oxygen
hanifa pia uko hapa
Hypoxia is the lack of oxygen concentration in the blood. Therefore, tissues will receive a low concentration of oxygen. Usually our bodies respond to Hypoxia by stimulating erythropoiesis in red bone marrow.
hypoxia is the lack of oxygen in blood absolutely.
hypoxia: is a condition in wich the concentration of oxygen goes down in tissue or all over the body but the low concentration of oxygen in blood is called hypoxiemia.
where is present Glenoid Cavity ?
A- Reply
what is the muscular tissue
Md Reply
muscular tissue is a type of tissue that provide to help in cotraction to aur body.
What's the difference in epithelial, connective, muscular and muscle tissue
and it's similarities
what is limb bone
Akshu Reply
this are bone attaching or joining to the axial bone.axial bone including skull,vertebrate and ribcage
how many bones make up the skull?
22 bones
where is present Glenoid cavity ?
how many bone in skull
almost there are 8 bones in skull
Explain the stages of mitosis and cell division
Bella Reply
Bella, this is a very long process to detail by text. However, to keep it brief, mitosis has four phases in order: prophase, metaphase, anaphase, and telophase which sometimes followed by cytokinesis. Note that some cells do not always do the cytokinesis phase.
As a result, some of the cells in the body are multinuclear (osteoclasts for ex).
explain further
difference between mitosis and meosis
In mitosis, two genetically exact daughter cells (somatic cells) are produced and they are diploid. In meiosis, four genetically unique cells (gametes) are produced and they are haploid.
Meiosis only occurs in reproductive organs. Mitosis is a type of asexual reproduction and is involved in tissue growth and regeneration(repair).
mitosis > Diploid to Diploid meiosis > Diploid to Haploid
systems of human body
Udezue Reply

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