The Senses
How do we experience
daily living through our
senses?
The Eye
The Ear
The Hand
The Nose
The Tongue
A Baby is Born
When a baby is born he opens his eyes
first. The baby sees the world for the
first time. The baby then hears all
the commotion around him. Then,
the baby feels the doctor hold him/
her. The baby then smells the new
world around him/her. When the baby
gets home, the mom or dad feeds
him/her baby food.
Sight
When light rays pass through your pupil, the muscle called
the iris makes the size of the pupil change depending on
the amount of light that’s available. You may have
noticed this with your own eye if you have looked at it
closely in a mirror. If there is too much light, your pupil
will shrink to limit the number of light rays that enter.
Likewise, if there is very little light available, the pupil
will enlarge to let in as many light rays as it can.
Just behind the pupil is the lens and it focuses the image
through a jelly-like substance called the vitreous humor
onto the back surface of the eyeball, called the retina.
The retina, which is the size of your thumbnail, is filled with
approximately 150 million light sensitive cells called rods
and cones. Rods identify shapes and work best in dim
light. Cones on the other hand, identify color and work
best in bright light. Both of these types of cells then send
the information to the brain by way of the optic nerve.
Hearing Story
Walking in the park you hear birds chirping,
kids screaming, people talking and even
twigs breaking. At home you can listen to
TV and watch your favorite TV shows and
also listen to music. Beep beep beep! When
you wake up in the morning the sound of
the alarm wakes you up you can go to
school. Also when you go to school you
LISTEN to you teacher and also to you
friends then you hear of the excitement of
when it is time to go home
Hearing
The ear is broken into 3 sections the outer ear, the middle ear
and the inner ear
Outer ear – has the pinna and the external canal
Middle ear – has bones to keep things from going into your ear
and these bones are called , The hammer, Anvil, and the
stirrup and these 3 bones are the smallest bones in the bones.
Inner ear – has the cochlea which has fluid in it that maintains
your balance
- How you hearIn humans and other vertebrates, hearing is performed mainly by
the auditory system vibrations are detected by the ear and
translated into nerve impulses that are perceived by the brain.
Touch Story
You are riding your bike. You can feel the cool wind on
your face. Then, all of a sudden, you crash into a tree!
You scrape your knee and bite your tongue. Ouch!!!!! The
injury on your knee is much worse, but the one on your
tongue hurts much more. Why?
This is because you have more touch receptors in
your tongue then in your knee. Different parts of the body
have different amounts of touch receptors. We have
receptors for temperature, pain pressure, and much more.
Without these receptors, it would be very hard to do our
everyday activities. You could get burned alive without
even knowing it!
Touch
Unlike your other senses, this sense is located all over your body. But, your
main touch organ is your skin. Our skin acts as a protective covering between our
internal body organs and the outside world. Also the skin and our sense of touch,
we wouldn’t be able to function in our daily lives. Without our sense of touch, it
would not hurt when you cut yourself, and you would not know to put a bandage
on it, and it could get infected. It could even led to blood disease.
When you touch something, the information of touch is carried by the nerve
cells to the spinal cord. Then, the message is moved to the brain. The brain sends
signals to the body that tell it what to do. For example, suppose you touch a cup of
hot chocolate. Sensory nerves send the information of heat to the spinal cord. The
spinal cord sends the message to the brain. The brain tells the muscles in your
arm to move away from the heat. If you could not feel the heat or the pain, your
body would get hurt very easily.
The huge network of touch receptors in the skin is known as the
somatosensory system. This system is responsible for all the sensations we feelhot, cold, smooth, rough, pressure, tickle, itch, pain, vibration, and more.
Within the somatosensory system, there are four types of
touch receptors: mechanoreceptors, thermo receptors,
pain receptors, and proprioceptors.
Taste Story
• It was lunchtime. I was very hungry
because I was working all morning. My dad
was cooking hamburgers on the grill and I
could smell it in my room. As I went to
take my first bite, I dropped the burger
quickly. I had burned my tongue! Even
though it hurt, I still ate it. It was hard to
taste the burger, so I had to imagine what
all the flavors would taste like together. It
is always good to blow on your food!!!
Taste
• You have five tastes: sweet, sour salty,
bitter, and umami
• There are 50-100 taste cells representing
each taste sensation
• The taste buds are associated with papilla,
elevations on the tongue
• Taste buds are found on the roof of the
mouth, tongue ad cheek
• You have about 10,000 taste buds
• Stimulated by smell and texture
• Taste belongs to chemical sensing system
• This sense declines with age
Smell Story
On an early Saturday morning, some
people go for a jog in the park. They
can smell the dew on the grass and
the blooming flowers. Shhhh. It’s
raining ! Wow, during the spring you
can even smell the rain. Time to go
home. People make coffee or tea.
They can smell the coffee or tea. Then
, they relax for the rest of the day
Smell
Olfaction is the sense of smell. This sense
has specialized sensory cells in the nasal
cavity. Humans have 2 distinct olfactory
systems: the main olfactory system, and
the accessory olfactory system. The main
olfactory system detects volatile
chemicals and the accessory system
detects fluid-phase chemicals. The
chemicals which activate the olfactory
system are called odors. They are low in
concentration.
Fun Facts
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Everyone has a unique sense of smell, except for identical twins
You can’t smell while you are asleep. You don’t smell coffee
then wake up; rather you wake up then smell coffee
Girls have more taste buds than boys
Taste is the weakest of the five senses
The whole middle ear is no bigger than a M&M candy
The ear never stops working, even while you are asleep.
A newborn see the world upside down. It takes a while for the
baby's brain to learn to turn the picture right-side up.
If you only had one eye, everything would appear twodimensional. (This does not work just by closing one eye.)
The least sensitive part of your body is the middle of your back.
You have more pain nerve endings than any other type.
We use our senses in the simplest ways:
such as eating a cupcake or smelling a
flower.
A prickly cactus
Resources
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Science Textbook- Glencoe Science Voyages Level Green
American Natural History Museum-Brain Exhibit
http://library.thinkquest.org/3750/taste/taste.html
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/T/Taste.html
http://en.wikipedia.org/wiki/Taste
http://library.thinkquest.org/3750/smell/smell.html
http://yucky.discovery.com/flash/body/pg000150.html
http://idahoptv.org/dialogue4kids/season10/senses/facts.cfm
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/V/Vision.html
http://library.thinkquest.org/3750/touch/touch.html
http://serendip.brynmawr.edu/exchange/node/4356
http://en.wikipedia.org/wiki/Hearing_%28sense%29
http://library.thinkquest.org/3750/hear/hear.html
http://www.umm.edu/imagepages/8684.htm
Created By:
Katherine Gange
Tyler Scott
Jade Schoolcraft
Justin Roman
Larry Johnson