Our senses allow us to learn, to protect ourselves to enjoy our world.
Can you imagine what it might be like to live your life without any of your
senses? The five senses are:
Our sense of taste comes from the taste buds on our tongue. These buds are
also called
papillae (say: puh-pih-lee). But, the sense of smell also affects
our taste.
The tongue is only able to taste four separate flavors: salty, sweet, sour
and bitter. But, you might ask, how come different sweet foods taste different
if there are only four flavors? That is because a combination of sweet and
salty could be your favorite candy. And the combination of sweet and bitter
could be the chips in your chocolate chip cookie. Everything you taste is
one or more combinations of these four flavors.
Not only can your tongue taste, but it also picks up texture and
temperature in your food like creamy, crunchy, hot or dry.
Our sense of sight is all dependent upon our eyes. A
lens at the front of
the
eyeball helps to focus images onto the
retina at the back of the eye.
The retina is covered with two types of light sensitive cells - the
cones and the
rods. The cones allow us to see color and the rods allow us to see
better at night and also aid us in our peripheral vision. All of this information
is sent to the brain along the
optic nerve.
The images sent are actually upside down and our brain makes sense of what
it receives by turning the vision right side up. The brain also uses the images
from two eyes to create a
3D (three dimensional) image. This allows us to
perceive depth.
Some people are not able to tell red colors from green colors. This is called
color blindness. Others, through injury or other conditions, have little to
no sight at all.
Here is a
story of a woman who was born blind but through surgery was able to see.
The skin is the largest organ in our body and contains the most endings.
View a
diagram of the skin.
The sense of touch is spread through the whole body.
Nerve endings in the
skin and in other parts of the body send information to the brain. There are
four kinds of touch sensations that can be identified: cold, heat, contact,
and pain. Hair on the skin increase the
sensitivity and can act as an early
warning system for the body. The fingertips have a greater
concentration of
nerve endings.
People who are blind can use their sense of touch to read
Braille - a kind
of writing that uses a series of bumps to represent different letters of the
alphabets.
Our nose is the organ that we use to smell. The inside of the nose is lined
with something called the
mucous membranes.
These membranes have smell
receptors connected a special nerve called the
olfactory nerve.
Smells are made of fumes of various substances. The smell receptors react with the
molecules of these fumes and then send these messages to the brain. Our sense of smell
is capable of identifying seven types of sensations. These are put into these
categories: camphor, musk, flower, mint, ether, acrid, or putrid. The sense
of smell is sometimes lost for a short time when a person has a cold. Dogs
have a more sensitive sense of smell than man.
In addition to being the organ for smell, the nose also cleans the air we
breathe and impacts the sound of our voice. Try plugging your nose while you
talk.
Smell is also an aide in the ability to taste.
Our ears, which help us hear, are made of two separate parts; the
outer ear and the
inner ear.
The outer ear is the part that others see. It works like
a cup to catch sound as it travels past our heads. This part is made of
cartilage and skin. From here, sound travels to the
tympanic membrane and then onto the inner ear by the three smallest bones in your body. The inner ear is also called the
cochlea and is a spiral shaped tube which
translates vibrations into sound and sends that message to the brain through the
auditory nerve.
The brain uses the sounds from both the left and the right ear to determine
distance and direction of sounds.
Additional Senses
organs:
a part of a living organism that has a specific job
In addition to sight, smell, taste, touch, and hearing, humans also have
the sense of balance, pressure, temperature, pain, and motion. These various
"new" senses all work together and may involve the coordinated use of the
sense
organs.
The sense of balance is managed by a complicated network of
various body systems. Any quick change to any of the five senses can cause
the feeling of dizziness or unsteadiness. You might have experienced this
while riding in a car or turning quickly.
Take a peek at the 
Check out a 
