The sense of touch

We use our skin to touch and feel objects.

Nerve sensors in the skin detect the temperature –hot, cold, warm- and texture –rough, smooth- of objects.

We feel temperature and texture.

1. Temperature: hot or cold.
2.  Texture:

Rough or smooth.
Hard or soft.

The sense of smell

 We can smell with our nose.

The nose has 2 external cavities called the nostrils. They take the air into the nose.

The sense of tasting

We taste with our tongue to find out the flavour of food. The sense of smell is also important to taste.

The taste buds contain the receptors for taste.

Taste buds are located in the tongue according to the flavor they can distinguish:

-salty and sweet: near the front.

-sour: at both sides.

-bitter: at the back.

Taste, or gustatory perception, is one of our basic senses. It tells us from early childhood what is edible and what is not, what is good for our body and what can be potentially dangerous. Taking into account how important the sense of taste is for us, it is surprising how little we know about the underlying neurological mechanisms that produce the sensation of taste. 

The food has moleculs that the tonge perceives and informs to the brain about the taste and if it is good or bad. 

Parts:

There are 9 parts:

Epiglottis, lingual tonsils, circumballate popilloe, median sulcus of the tonge, dorsum of the tonge, fungiform popillae, foliate popillae, palatine tonsils and palatopharyngeal arch.

Most of people think that they are 5 tastes, but actually there is a new one, which is umami.

Finally, here is a video about umami.

 

The sense of hearing

We use our ears to hear things. Some sounds are nice, such as music, and others are loud and noisy; for instance, someone shouting .

The ear: sounds enter the outer ear and travel to the eardrum along the ear canal.

Three small bones, the hammer, anvil and stirrup, make sounds louder.

The sound goes to the brain through the auditory nerve.

The sight

The sense of sight let us see colours, shapes, sizes, brightness  and distances. We need light in order to see the objects. Eyes Eyes are the organs for sight. Eyes have different parts: The parts that protect the eye The eyebrows and the eyelashes prevent harmful things,  like sweat or dust, from entering the eye. There are two eyelids on each eye. The upper eyelid is  larger and it opens and closes when we blink. The tear glands produce tears.

• The parts responsible for vision:
  
  
• The iris is the coloured part of the eye. It controls the amount of light that enters the eye.
  
  
• The pupil is in the center of the iris. Light enters through the pupil to the inside of the eye.
  
  
• The lens is inside the eye. It is behind the pupil and the iris. It also helps us to see objects in focus.
  
  
• The retina is at the back of the eye. The light entering the eye travels until it reaches the retina. The optic nerve is attached to the retina.

How does the sense of sight work? How do we see?

Light enter the eye through the pupil. It travels through the lens; the lens focuses the objects we see.

When the light reaches the retina, it percieves different sensations: colour, shape and size.

This information goes to the optic nerve. This nerve carries the information to the brain.

The five senses

aalavech · The five senses and the interaction function