Let us first try to be perfectly ordinary!
You have five main senses:
Sight, hearing, touch, taste and smell.
They keep you informed and in touch with the outside world!
The information is collected by sensory receptors, these specialized cells encrusted and embedded in our sensory organs, as in your nose for example.
Your nose, could not "smell" alone, it receives information, and they are sent messages through a network of nerves to the brain,
Where the analysis proceeds!
The eye receives incredible detailed information from the world around you.
The main and most important element in this process is the light.
The light rays bounce on the object and enter the eye through a slightly curved transparent layer called: the cornea.
The lens of the eye concentrates the light and the light rays on the retina constituted by luminous receptors at the back of the eyeball.
An inverted and upside-down image is then formed.
Since the retina,
Electrical signals transmit the image to each opposite hemisphere of your brain.
Thus, the nerve at the start of the rightretina will transmit the information to the left hemisphere, and vice versa!
We talk about optic chiasma, "chiasma" for crossing through the nerves eye and the image is seen then in the good position!
The retina is lined with millions of receptors sensitive to light: cones and sticks.
The sticks discern the black and the white while the cones perceive the colors.
The iris is the colored circle surrounding the pupil.
Muscles in the iris contract to allow the pupil to close, reducing the passage of light rays when they are too intense or when there is too much sun.
These muscles relax and allow the pupil to expand when the light is more subdued, letting more light rays enter to help us see!
Mirror in hand and eyes closed.
After 10 seconds, open them and observe how your pupil closes to keep and prevent from the light!
The sounds are the result of the vibration of the air molecules.
These vibrations or sound waves travel through the air in all directions!
These waves penetrate your ear and vibrate your eardrum.
After passing through the auditory canal, the sound vibrations pass through a chain of ossicles the size of a grain of rice:
The hammer, the stirrup and the anvil!
These bones will transcribe into decodable and decipherable signals in the manner of morse signals.
The vibrations are thus amplified before passing through the cochlea,
An extremely sensitive electronic receiverthat transforms vibrations into a nervesignal!
Finally, from the cochlea a series of auditory nerves will tramit these nervous signals to the brain where the original sound will be displayed!
You have several million taste buds on the entire surface of your tongue.
They allow us to discern the four flavors of bases:
Sweet, salty, sour and bitter!
In order to experience the taste, the flavors of the ingested food must dissolve in the saliva, in order to be able to cross tastebuds
Eyelashes located on the top of the gustative pores will collect the molecules to be analyzed and transmit the information in the direction of the taste nerve.
Along with taste nerves are send serve signals to the center of taste located in the brain!
Signal analysis and flavor identification would be proceeded!
Taste in the strict sense is something more restricted than the use made of it in everyday language.
When we say "this dis has a good taste!", We mainly make reference to sensations that involve very much smell!
The tastes perceived by our tongue alone are very limited!
How everything is tasteless when you have a stuffy nose!
The gustatory map is also an incorrect preconception, it is not the tip of the tongue that perceives the sweet, and the sides the salty...
In reality, the zones indicated are very correct, but on each of these zones one can perceive the five tastes.
At the level of these areas are the papillaeof the tongue, which contain the gustatory buds, themselves formed by cells charged with the perception of taste.
Although each cell is dedicated to a taste among the five, in a given region of the thongue one finds the five types of cells!
In addition, there is a fifth taste sensation discovered in the 20th century that was baptized umami, which means "delicious" in Japanese.
Chemically speaking, perception of the umami is stimulated by sodium glutamate,
A molecule found naturally in meats, cheese, soy sauce, and ripe tomatoes.
Agro-food manufacturers had well understood the trick and often add glutamate sodium to food to serve as a "flavor enhancer"!
The skin, a simple envelope?
Other than the "clothe" of the body, the skin possesses a set of sensory receptors capable of sensing and detecting a whole range of degrees of heat,
Degree of cold, touch sensitivity and pressure.
Let's see how these sensors work!
The sensory receptors of the skin are like clusters arranged at the level of the dermis.
The more these clusters are, the more sensitive the area is.
Thus, the fingertips possesses sensor receptors in number, whereas the skin of the back has very few!
As with the other senses, these receivers
receives messages and return electrochemical impulses to the brain, here to the brain area in charge of the "touch".
The skin is essential,
Without it, the muscles, bones, brain and other organs would be bare.
The skin protects you from infections, excess sun, extreme temperatures and other threats.
It can be repaired by itself in case of break or burn.
It stretches to grow at the same time as you.
The skin consists of three distinctive layers:
The dermis is one of the three layers that form the structure of the skin.
It is located between the epidermis and the hypodermis.
The dermis contains collagen, elastin and fibronectin which keep it supple and elastic, proteins that absorb water, and immune or texture cells!
The dermis receives the blood and redistributes it to the epidermis.
The dermis helps regulate body temperature, heal and eliminate toxins, evacuating them by sweat.
From an anatomical point of view, the epidermis refers to the outer and superficial layer of the skin.
It covers the dermis and hypodermis, deeper tissues of the skin.
The epidermis is mainly constituted on its surface by dead cells, or scales, which are continually renewed.
Four other cell layers make up the epidermis, the total thickness of which does not exceed 1 millimeter!
It is also covered on its surface by a protective film, the sebum.
The hypodermis corresponds to the subcutaneous adipose tissue below the dermis.
Rich in fat, this tissue is also made up of numerous blood vessels.
The fat cells in the hypodermis, which are more or less thick, are used as energy reserves to compensate for an absence or a punctual decrease in nutrients in the blood.
This connective tissue plays an important role in protecting the bones, the muscular system and the organs in case of possible external trauma.
The skin is covered with hair,
Except on the palms of the hands, the soles of the feet and the lips.
Glands produce sweat, which comes out to the surface by more than two million pores!
Sweat evaporates to cool the body,
In short, what a machine!
At the base of the epidermis are cells producing a pigment, or colored substance, called melanin.
The more melanin, the darker the skin.
When there are few, the skin is clear.
Freckles are actually small
When someone tans,
It is because the cells make more melanin to protect
The skin of the sun!
It's the world seen from the light side!
The odors are due to invisible particles: the fragrant molecules!
When breathing, only a small number of these molecules enter the respiratory cavity
and dissolve in the nasal mucus; Result, a very small number of molecules arrive
to the olfactory receptors!
You must consciously "aspire" the air through your nose to "smell well"!
When you inhale to smell a rose, for example, more
Olfactory molecules travel more deeply through the nostrils directly to olfactory receptors.
These receptors are placed in the nasal cavity like tree roots suspended in a cave...
From these receivers,
The olfactory molecules travel by electric impulses to the olfactory bulb.
These electric impulses then travel from the olfactory bulb constituting the first facial nerve
To the brain where they will be recorded and analyzed as an odor!
That's what i call a "team job"!