Summary: The senses

Summary: The sense of sight

 You use sight to distinguish the shape, colour and size of the objects and how far they are (distance).

The eyes are the organs of sight and they are protected by the eyelids, the eyelashes and the eyebrows.

The light passes through the cornea and through the pupil in the iris .The light comes to the lens and then to the retina that sends the information through the optic nerve to the brain.

Summary: The sense of hearing

The ears are the organs of hearing. They have three parts: outer ear (pinna), middle ear (ear canal) and inner ear.

The inner ear has three parts: eardrum, small bones and cochlea.

The sounds make the eardrum vibrate and those vibrations pass to the small bones and to the cochlea. The cochlea turns these vibrations into information that is sent through the auditory nerve to the brain.

Summary: The sense of touch

First you have to get an object to touch it. We can feel if it is smooth or rough; hot or cold; painful or agreeable with the skin. The skin is the organ of the sense of touch and there are the touch receptors that send the information through the nerves to the brain.

Summary: The sense of smell

The smell goes inside the nose through the nostrils, then reaches the olfactory epithelium inside the nasal cavity. Smell receptors in the epithelium send the information to the olfactory bulb in the brain.

Summary: The sense of taste

We use the sense of taste to distinguish flavours: sweet, salty, sour, bitter and umami. The tongue is the organ of the sense of taste and is covered with the taste buds that send the information through the nerves to the brain.