The Five Senses
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
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
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
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
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
The brain uses the sounds from both the left and the right ear to determine
distance and direction of sounds.
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
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.
Give This A Try
This is your opportunity to try an experiment in your senses. You will need:
- something you enjoy eating - an apple or banana
- an onion, cut open (adults should do the cutting)
Now, get someone to help you, by holding the onion under your nose while you eat the apple or banana. Take a deep breath and chew. What do you notice? Some of our enjoyment of eating comes from the fragrances of the food.
What foods do you enjoy smelling? Fresh baked cookies? Bacon frying?
Some fragrances will even bring back strong memories.