Understanding the Senses

Our body knows about things that many of us never really have thought about.

Have you ever smelled something that smelled so delicious or heard a noise coming from another room?

Have you ever put your hand in freezing water and noticed how it makes you feel? Our body knows about these things because of our senses.

Our body is constantly using the five sense, even when we do not recognize that this is happening.

When you are eating, the body is using the sense of taste and smell, when you are doing homework your body uses the sense of feel and the sense of sound.

Exploring and interacting in the world is easier with our five sense, these senses include hearing, smelling, tasting, touch and sight.


People need their sense of sight for so many reasons. When you are reading a book, walking, watching a movie or when you are doing any daily activities, your sense of sight is used.

Your body is constantly looking around and “taking pictures” of the world around you and sending these pictures to your brain so that you can figure out exactly what you are seeing.

The images that your body processes help you to understand what is going on around you.


When you are listening to music or talking to a friend, you are using your sense of sound.

Inside the ear canal is where sound starts, as it enters through the canal and then while in your ear, it vibrates your ear drum back and forth.

This movement is called vibrations and these vibrations are passed on to the brain, where the brain will process the sounds that you are hearing.

The different speed of the vibrations helps to determine the pitch of a sound.

The faster that the sound vibrates, the higher pitch the sound will have. The slower the sound vibrates, the lower pitch the sound will have.


When you eat and drink, you are using your sense of taste. When something enters into your mouth, your tongue immediately begins to use the sense of taste.

Tiny hairs and bumps on your tongue called taste buds, help to send messages to the brain as to what we are tasting.

There are five different flavors that can be recognized in most humans and these are sweet, bitter, salty, sweet and umami. Umami is a flavor that is savory.

Our body sends messages to the brain to tell our body if we should spit something out or swallow it.

When you put spoiled food in your mouth, your taste buds send messages to your brain that you should spit it out.

Smell and Taste

Smell and taste work together because both smell and taste use the same receptors called chemoreceptors.

These receptors help our bodies to recognize when there is a chemical environment.

Smell and taste work together because they coordinate both the smell and the taste at the same time, and this is how different flavors are created.

If someone has a congested nose, they may not be able to taste something that they eat.


All of the information that our body receives by our sense of sight goes to the brain through nerve endings.

The sense of touch is the same, our body sends messages to the brain through the nerve endings so that we “feel” what we are touching.

The top layer of our skin is called the epidermis. This epidermis has nerve endings that send messages to your brain to tell you what kinds of things you are feeling.

When your brain figures out what that thing is that you are touching, your brain tells your body what to do.

For example, if your friend puts ice on your skin, your skin tells your brain that it is cold and then your body reacts by screaming or moving.

Sense of Touch

Our sense of touch does many things. When someone touches you, you feel that someone is touching you and how hard they are touching you.

The body uses nerve endings to help you to feel pressure.


Another thing our body feels is pain. If we touch something that is pointy or hot, we immediately take our hand away to stop the pain.

That is how our sense of touch protects us. It is important to note that even though our body has hair and nails that these things do not contain nerve endings.

When you cut your hair or nails, it does not cause pain because there are no nerve endings in these parts of the body.

Touch Receptors

There are four different touch receptors; mechanoreceptors, thermoreceptors, pain receptors and proprioceptors located in our bodies.

Mechanoreceptors help us to know pressure, vibrations and texture. Thermoreceptors help us to feel temperature.

Pain receptors let us know when we are hurt or injured such as cut or scraped, burned or stung by an insect.

Proprioceptors help us to know what is happening around our environment such as going from hot to cold.


Smelling is a very important sense that we have. The sense of smell starts in your nose but it uses other parts of your body to help it work.

Olfactory Nerve

When something has a scent, the nose is very sensitive to this.

As the smell travels through the air, small pieces of the scent can tickle the nerve endings of the olfactory nerve, and the olfactory nerve carries the message to your brain, telling you what the scent is.

The nerve is located high on the nasal passage, so we do not always smell things right away because it takes a while for the scent to travel in the air and up the nose to the nerve endings.

Smell is sometimes called, olfaction, because the scent is through the olfactory nerve.

Memory and Smell

The sense of smell is linked to our memory because when we smell something familiar, it sometimes makes us think of a memory that was associated with that smell.

Sometimes though, when we get used to certain scents, our body gets used to them and we do not notice them as much.

Our sense of smell is important and to help us enjoy life, but it also can help us to be safe in case we smell a fire or something burning.

Smell and Taste

When someone has a cold, it makes the sense of smell hard and it affects the way that we taste our food, as well.

Facts about the 5 Senses:

  • With smell, people can smell over a trillion different scents.
  • Fun fact! Dogs have more than 44 times the scent cells than humans.
  • Our skin protects our body from the outside world.
  • Our sense of touch is controlled by a huge amount of nerve endings in the skin and this is known as the somatosensory system, it helps us determine hot, cold, rough, pressure, tickle, pain, vibrations and more.
  • When your hand touches an object, receptors in the skin communicate with the brain, which then communicates with the body.
  • Our body hears things when vibrations activate the hairs inside the ear and communicates to the brain what the sound is.
  • The pinna, a funnel like shape in the ear, directs sound to the ear canal and into the eardrum.
  • The eye has three layers for seeing.
  • Light is reflected and directed to our eyes and this is what helps us to see.
  • Our eyes are shaped like a ping pong ball.
  • The tongue has over 100,000 taste buds.
  • When your body uses saliva to break down the food, it sends receptor cells found in your taste buds to the nerves in your brain to help you determine what you are eating.

What Did You Learn?

  • How do the sounds that we hear reach the brain? Sounds that we hear, reach the brain through the auditory nerves.
  • Why do sounds have different pitches? Sounds have different pitches depending on how fast the vibrations enter into the ear. The faster the vibrations, the higher the pitch. The slower the vibrations, the lower the pitch.
  • How does the nose know how something smells? The smells enter the air and then the smells tickle the small hairs that are located on the olfactory nerve. When this happens, the smell is translated to the brain.
  • Is the sense of smell and the sense of taste related? How? Smell and taste are related. This happens because the body uses chemical receptors to determine both smell and taste. If one is not working, the other sense may not be as strong. For example, if someone has a stuffy nose, they may not be able to taste something.
  • What are taste buds? Taste buds are tiny hairs and bumps that are nerve endings. These help determine taste.
  • If you touch a hot stove or a cold piece of ice, how does your hand know the difference? Nerve endings that are located in the skin help to determine if something is hot or cold.