The document discusses the human senses of sight, hearing, taste, touch, and smell. It explains that sight involves both the eyes and brain working together to process visual images. The eyes capture images that are sent to the brain as messages to be interpreted. Hearing involves sound waves vibrating the eardrum and small bones of the middle ear, generating signals in the inner ear that are transmitted by nerves to the brain. Taste buds detect different flavors through receptors on the tongue. Touch receptors in the skin send signals to the brain about textures, temperatures, and sensations. Smell works through odor molecules activating nerve endings in the nose.

3. • Sight means your
ability to see.
• We use 2 parts of
our body to see.
• Your eye is a
complicated organ
made of many parts
that work together
• When we think of
sight many of us
think of the eyes
first
• But did you know
the brain is just as
important to seeing
as the eyes?

4. • The parts of the eye
work like a camera.
• They take pictures
of the things we
see
• These pictures are
turned into
message that are
sent to the brain
• Like a picture these
messages are
http://kidshealth.org/kid/htbw/ey processed, allowing
es.html us to see the world
around us

6. Sense of Taste
Have you ever thought about why foods taste different? It's really quite amazing. Your tongue
and the roof of your mouth are covered with thousands of tiny taste buds. When you eat
something, the saliva in your mouth helps break down your food. This causes the receptor
cells located in your tastes buds to send messages through sensory nerves to your brain. Your
brain then tells you what flavors you are tasting.
Taste buds probably play the most important part in helping you enjoy the many flavors of
food. Your taste buds can recognize four basic kinds of tastes: sweet, salty, sour, and bitter. The
salty/sweet taste buds are located near the front of your tongue; the sour taste buds line the
sides of your tongue; and the bitter taste buds are found at the very back of your tongue.

7. • Everyone's tastes are different. In fact, your tastes will change as you get older. When you were a baby,
you had taste buds, not only on your tongue, but on the sides and roof of your mouth. This means you
were very sensitive to different foods. As you grew, the taste buds began to disappear from the sides and
roof of your mouth, leaving taste buds mostly on your tongue. As you get older, your taste buds will
become even less sensitive, so you will be more likely to eat foods that you thought were too strong as a
child.

8. We have almost 10,000 taste buds inside our mouths;
even on the roofs of our mouths.
Insects have the most highly developed sense of taste.
They have taste organs on their feet, antennae, and
mouthparts.
Fish can taste with their fins and tail as well as their
mouth.
In general, girls have more tastebuds than boys.
Taste is the weakest of the five senses.

9. As an Out-of-School Project - Find Out More About Your
Sense of Taste
At home this evening with the assistance of your parents, do the
following activities and write two sentences about your experience in
your spiral notebooks.
Wipe your tongue with a towel so that it is dry. Now put a little
sugar on the dry part. You will not be able to taste it. Your
tongue must be wet for your taste buds to work!
Put some salt water on the back of your tongue. You can hardly
taste it. Now put it on the front. It tastes very salty. Different
taste buds are located on different parts of your tongue. So
tastes are stronger in some spots than in others.
Your sense of smell helps you taste things. Hold your nose tight
so that you can't smell anything. Now put a piece of onion on
your tongue. You can barely taste it. But as soon as you let go of
your nose you'll find that the taste seems much stronger.

10. Sense of Hearing
Like your other sense organs, your ears are extremely well-designed. In fact, they serve two very
important purposes. Do you know what they are? You were probably able to figure out that your ears help
you to hear sounds, but what you probably did not know is that your ears also help you to keep your
balance.
How You Hear
When an object makes a noise, it sends vibrations (better known as sound waves) speeding through the
air. These vibrations are then funneled into your ear canal by your outer ear. As the vibrations move into
your middle ear, they hit your eardrum and cause it to vibrate as well. This sets off a chain reaction of
vibrations. Your eardrum, which is smaller and thinner than the nail on your pinky finger, vibrates the
three smallest bones in your body: first, the hammer, then the anvil, and finally, the stirrup. The stirrup
passes the vibrations into a coiled tube in the inner ear called the cochlea.
www.shelledy.mesa.K12.co.us (Show video)

11. The fluid-filled cochlea contains thousands of hair-like nerve endings called cilia. When the stirrup causes
the fluid in the cochlea to vibrate, the cilia move. The cilia change the vibrations into messages that are
sent to the brain via the auditory nerve. The auditory nerve carries messages from 25,000 receptors in
your ear to your brain. Your brain then makes sense of the messages and tells you what sounds you are
hearing.
How You Keep Your Balance
Near the top of the cochlea are three loops called the semi-circular canals. The canals are full of liquid
also. When you move your head, the liquid moves. It pushes against hairlike nerve endings, which send
messages to your brain. From these messages, your brain can tell whether or how your body is moving.
If you have ever felt dizzy after having spun around on a carnival ride, it was probably because the liquid
inside the semicircular canals swirled around inside your ears. This makes the hairs of the sensory cells
bend in all different directions, so the cells' signals confuse your brain.

12. What Did You Say?
Did you know that some people have trouble hearing and others cannot hear at all? Well it's true. When a
person can't hear well, a hearing aide can sometimes help them hear better. However, people who are
entirely deaf have to rely on all their other senses to help process all of the information from the world
around them. They are deaf because of an illness or they were born that way. You can also lose your ability
to hear at an early age by listening to things that are very loud.
• Babies can get earaches because of milk backing up in the Eustachian tube, which causes bacteria to grow
and may cause hearing problems later in life.
• When you go up to high elevations, the change in pressure causes your ears to pop.
• Children have more sensitive ears than adults. They can recognize a wider variety of noises.
• Dolphins have the best sense of hearing among animals. They are able to hear 14 times better than
humans.
• Animals hear more sounds than humans.
• An earache is caused by too much fluid putting pressure on your eardrum. Earaches are often the result of
an infection, allergies or a virus.

13. Imagine This!
On a piece of paper, list some of the things you hear from the following sound
machine. In your spiral notebooks, write either a paragraph or a poem. Describe
what you hear and what it might look like. Make it so that someone else could see
and hear it.

14. Smell
• You smell as you breathe in air through your
nose. As the air goes through your nose to
your lungs, nerve endings in your nose detect
any smells.

15. Touch
• You touch & feel things with your
skin
• You have more pain nerve endings
than any other type.
• Your sense of touch helps you to
learn about size, shape, texture and
temperature
• When you touch something, touch
receptors and nerve endings send
signals along nerves to your brain. If
you touch ice, touch receptors send
messages to your brain to tell you
that ice is very cold and hard.

16. State Standards
• STATE GOAL 23. Understand human body systems and factors that influence growth and development.
• Why This Goal Is Important: To achieve healthful individual development, students need to understand human anatomy
and physiology, nutrition, stages of growth and development, avoidance of harmful actions and the characteristics of good
health habits. Early learners begin with basic recognition of body systems and growth stages. As students progress, they
understand how systems work together and how individual actions affect health. As they themselves grow and develop,
students can learn to enhance the process throughout their school years and later life.
• A. Describe and explain the structure and functions of the human body systems and how they interrelate.
• EARLY ELEMENTARY
• LATE ELEMENTARY
23.A.1 Identify basic parts of body systems and their functions (e.g., heart, lungs, eyes).
• 23.A.2 Identify basic body systems and their functions (e.g., circulatory, respiratory, nervous

17. Resources
www.librarythinkquest.org
www.shelledy.mesa.K12co.us
http://faculty.washington.edu/chudler/chtouch.html
http://library.thinkquest.org/3750/touch/touch.html
Landau, E. (2009). A true book: the sense of touch. New York:
Children’s Press.

18. Vocabulary Words
Receptor
Sensory Nerves
Vibrations
Sound waves
Eardrum
Hammer
Anvil
Stirrup
Cochlea
Cilia
Auditory Nerve
Semi-circular canals
Eustachian tube