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We use senses everyday for many different purposes, they are parts of our body that tell us what is going on in the world outside our bodies. Different senses include sight, taste, hearing, smell, touch and balance. We see through our eyes, taste with our tongue, hear and balance with our ears, smell with our nose and touch with your whole body on the outside. Without senses, there would be no point for us living, we wouldn’t know what we are doing or where we are going.

The sense we mostly on rely is sight, but for blind people, it is not that simple. They use touch and hearing most. Different animals sense of sight are for different uses, humans sense of sight is to spot other humans. When we are walking down the street, we see something’s that we do not intend to. Basically your eyes stray off and look around at other people. When you see something, there are light beams reflecting off the object and entering into your eye through the cornea, a thick transparent protective layer on the surface of your eye and in to the pupils. When we suddenly go into the dark it normally takes a while for our eyes to adjust to the dark. This is because when we enter the dark, our pupils get larger so our eyes adjusting to the dark are our pupils getting bigger.

We use taste quite a lot, it is also what helps us survive when we are young, we do not like bitter or sour things because in nature bitter and sour plants normally mean they are poisonous. We like sweet, sugary things because this means more energy. Different parts of our tongue taste different types of taste: the tip tastes sweetness, the back tastes bitterness, and both sides taste sourness.

Smell contributes to your taste a lot, when you try tasting something while holding your nose, most of the time you do not know what it is. This is because before the food goes into your mouth, your nose picks up the aroma from the food. Humans can detect about 10’000 different smell molecules, so we can enjoy or stay away from anything we smell. Compared to dogs, humans can hardly smell at all because dogs have about 25 times more smell receptors than humans do. Dogs are used a lot when police are looking for a missing or wanted person. Every time we breathe in, a current of air enters your nostrils and to an area where there are millions of smell receptor neurons. The neurons pick up the smell and sends signals to the brain which tells you if you like the smell or not. Sometimes smells can bring you back memories from the past because your brain remembers the smell from that time.

When we pinch ourselves, it hurts. This is because we have millions of nerve endings that tell us what something feels like. They can feel hard or soft, wet or dry, hot or cold, feels good or painful etc. When the nerve endings finds out what it feels like, it sends a message through the spinal chord to your brain. It’s all up to your brain to tell you if you feel good or hurt. When you expect something to hurt, it usually will a lot more than if you thought it was not going to hurt. Some parts of the body are much more sensitive than other parts of your body because there are more nerve endings there. In fact, if your body were in the same proportion in size with nerve endings, the only parts of your body that would be the same size would be your back and legs. Your head, arms, fingers, feet, toes, lips, and tongue would swell up a lot.

Both hearing and balance are controlled by the ear (the brain really – the ear just tells the brain what is happening). Human ears are very smart (not the ear – the brain again) because they can recognize different sounds and they can block out surrounding sounds. That is why you can talk with someone in a large crowd with lots of noise. When something makes a noise there is a vibration in the air and your outer ear funnels the sound into your middle and inner parts of your ear. As the sound goes into the middle ear, it hits the eardrum causing it to also vibrate. The eardrum vibrations make the three smallest bones in you body vibrate. The bones send the vibration into a tube called the cochlea. The cochlea contains many hair like nerve endings called cilia. These convert the vibrations into messages that are sent to the brain via the auditory nerve and the brain understands what is being said. Except that the drum vibrating, the three bones vibrating, vibrations sent down the cochlea, vibrations converted by the cilia and sent to the brain al happens way quicker than it sounds.

So the human senses can sense a lot of things that is happening around you at the current time.