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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.

Mandible

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

How do you differentiate Haversian canal and Volkmann canal?
Holly Reply
These are differentiated based on location. Haversian canal are present right in the middle of the osteon. the Volkmann canals are located to the sides of Haversian canal and their blood vessels and nerve fibers invade deep into spongy bone in long bones.
Carmelo
thank you
Holly
What are coronal arteries?
julie
The coronary arteries/veins are the group of arteries and veins that supplies the myocardium of the heart.
Carmelo
What is augment
Safia Reply
I don't know
Taufik
Google works wonders at answering questions..
Mel
how to identify tissues cells under a microscope
Carla Reply
any advice on how to identify tissue cells under a microscope?
Carla
structural and function of the living part
Parthiban
What is homeostasis
Haji Reply
ability of living organisms to adjust it internal environment to maintain a stable equilibrium
famuyiwa
how to identify tissues cells under a microscope
Carla
what is the anatomy
aamina Reply
anatomy is the branch of science concerned with the bodily structure of humans animals and other living organisms, especially as revealed by dissection and the separation of parts.
Misikir
what are silhouettes
Magret Reply
is dis Medical term?
Preity
yes
Magret
but I don't know what it means
Magret
silhouette outline of a figure. The sharpness of the silhouette is a function of the shape, size and density of the object. This is most marked in radiography. basketball-shaped silhouette the enlarged cardiac outline seen in the dorsal-ventral view of the thorax in a dog with chronic pericardial
Callisto
Homeostasis
Haji
it's the first stage of wound healing that involves vasoconstriction platelet plug formation and blood clotting
famuyiwa
Levels of complexity
julie
sorry that was fast hemostasis
famuyiwa
Kkkk
julie
Anti there is homeostasis and haemostasis
julie
yes , homeostasis is the abiltity of a living organism to adjust it environment to maintain a stable equilibrium
famuyiwa
Thank you Alice, how about Haemostasis?
Christina
hemostasis is the process of regeneration of brown blood vessels to prevent bleeding from occurring. Hemostasis includes vasoconstriction by the tunica media, plalet plug formation to prevent escaping of blood out of the vessel, and blood clotting which Involves the deposit of fibrin into the plug.
Carmelo
broken blood vessels*
Carmelo
is it true, suppose if a person does something wrong like having bad habitat. Is there any connection to the kids that person going to give birth to?
Sherin
That is a very interesting question! Their has been positive correlations in data about specific behaviors occuring between parents and children. For example, alcohol addiction has been shown to be a possible trait of behavior to be passed down to generations by evaluating genes.
Carmelo
Another example is that certain individuals are more prone to mental disorders like severe depression than others based on genetics. However, also keep in mind that the environment in which you are surrounded daily plays a part in developing specific behaviors.
Carmelo
why are postsynaptic ganglionic neurons unmyelinated
Callie Reply
Postganglionic motor neurons are unmyelinated because the lack myelin sheath. The myelin sheath on the peripheral nervous system is composed of Schwann cells wrapped around the axon inside the endoneurium.
Carmelo
they lack*
Carmelo
Postganglionic (and preganglionic) motor neurons belong to the division of the autonomic nervous system. In contrast, the somatic nervous system contains only one long thick myelinated somatic presynaptic motor neuron.
Carmelo
anatomy defination in urdu
Atif Reply
human body largest organ.....
jasveer Reply
liver
JOY
liver
Lem
Skin
amen
lungs
Zamiir
liver and skin
Marina
skin
brian
by mass is liver but externally is de skin
Kumsah
all answers Are correct
brian
no
Rehman
liver is the largest gland of the body but skin is the largest organ of the body
Rehman
so please what is the answer now
Marina
afcous skin.because difference between Gland and organ
Safiya
Only the skin
Williams
The largest organ is the skin and the liver is a gland
Williams
skin is the largest organ of the body
Denis
liver
julie
it's the skin
trinna
skin 100%
Mallikharjun
largest organ- liver largest system- Skin
Shahriar
largest organ is skin because it covers the rest of the organs
Syed
liver right answers
nisha
liver
Justine
skin
Areej
liver is largest gland
Areej
skin is largest organ liver is largest gland femur is largest bone thyroid gland is largest endocrine gland seratus muscle is largest muscle
Tanveer
sciatic nerve is largest nerve
Tanveer
portal vein is largest vein
Tanveer
GIT is largest tube in body
Tanveer
explain about cerebrum cereblum and pons medulla
Tanveer
Nervous system anotomy and physiology
Tanveer
skin is the human body's largest organ
Kimbley
@Tanveer, the cerebrum consists of the cerebral cortex, corpus callosum, hippocampus, and basal ganglia. The cerebellum is located inferior to the occipital lobe. The pons and medulla are part of the lower brainstem.
Carmelo
The cerebral cortex are divided into 4 lobes and control functions such as: thinking, learning, speech, sensory perception, motor functions, hearing and vision, etc. The cerebral cortex is mainly present only in mammals due to evolution. The hippocampus plays a main role in memory formation.
Carmelo
The cerebellum works together with the motor cortex and other parts of the brain to coordinate and fine tune muscular activity. The pons and medulla control autonomic functions such as: sleep, respiration, swallowing, vomiting, heart rate, vasomotor control and more other things.
Carmelo
skin hai friend
Tilak
what is the biliary tract
famuyiwa
The biliary tract involves the liver, gallbladder, and bile duct. Certain liver cells (hepatocytes) synthesize bile salts derived from cholesterol in response to Secretin hormone. The gallbladder stores the bile. Gallbladder releases bile to the bile duct in response to Cholecystokinin hormone.
Carmelo
The role of bile is to emulsify fats so that they can be easily broken down and absorbed by the enterocytes into the lacteal vessels.
Carmelo
what is the difference between negative feedback loop and positive feedback loop
famuyiwa
what is cholesterol
Kay
unsaturated fats
famuyiwa
so what is the main purpose of anomaly
Kay
Cholesterol is a waxy substance your body uses to protect nerves, make cell tissues, and produce certain hormones.
Favour
Cholesterol is a type of lipid and it is a nonpolar molecule. The molecule is mainly composed of hydrocarbon chains. Cholesterol is synthesized in the smooth endoplasmic reticulum in eukaryotic cells, and is the main building block material for steroids, Vit D, and bile salts.
Carmelo
Negative feedback loop reverses any change back to its set point. For ex, when your internal body temperature rises above 98.6 F, your hypothalamus triggers your dermal blood vessels to dilate and activate sweat glands through sympathetic motor nerves so you can sweat and cool off back to 98.6 F.
Carmelo
Positive feedback loop amplifies a change. For ex, during labor, oxytocin is released continuously in a positive feedback loop from the posterior pituitary gland to stimulate contraction of the myometrium so the baby can come out.
Carmelo
define homeostasis and explain it's importants
Adusei Reply
define the important life processes of humans
Adusei
how the bone marrow transplantation is done?
Tanveer
what is homeostasis
julie Reply
internal temperature of body
Sanket
Homeostasis is the internal constancy in which your body tries to maintain for optimal cellular functioning. For example, your body tries to maintain an internal body temperature of about 98.6F for optimal functioning of your body.
Carmelo
If a prolonged lost of homeostasis occurs, death of the organism will be the outcome.
Carmelo
Another example of homeostasis is that your body tries to maintain a specific blood sugar level, so that your cells can undergo constant cellular respiration and keep you alive.
Carmelo
homeostasis is the fairly constant internal changes of an environment (your internal environment).The temperature of a body must be kept between the range of 37.5°c
raphael
which tissue is more sensitive
Rit Reply
to what?
Lari
myasthenia gravis?
Selva
Myasthenia gravis is an autoimmune disease in which your own antibodies (produced by plasma cells) attack and inhibit nicotinic receptors at the neuromuscular junction.
Carmelo
As a result, acetylcholine will not bind to nicotinic receptors and now action potential is produced on the sarcolema. If no AP is produce, then there is no contraction of the muscle. For a long period of time, this will result in atrophy and muscle weakness.
Carmelo
and no action potential*
Carmelo
explain types of hypertension
Juli Reply
What is bulbar paralysis?
Roshni Reply
how can make penis larger
Marwat Reply
epithelial tissue connective tissue muscle tissue nervous tissue
Eliham Reply

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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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