Did you know that human beings have five senses? Well here they are…
- Hearing – Sounds are made up of vibrations, which are funnelled inside the ear by the outer ear. Soundwaves then travel down the ear canal and reach the cochlea. From here the messages are passed to the brain which interprets them into the sounds we know.
- Touch – There are about three million pain sensors in our skin. The fingertips are particularly sensitive, as they have 100 touch receptors. These touch receptors can detect light touch, pressure, vibrations, heat and cold. Some of these are contained in capsules while others are free nerve endings.
- Smell – Your nose can recognise up to 10,000 different smells. There are receptors high up in the nasal cavity that can pick up smell molecules and send signals to your brain, in order for you to remember the smell. People who can’t smell are called ‘anosmic’.
- Taste – The surface of your tongue is covered with tiny bumps (papillae). Some of them contain taste buds, and they are made up of cells with tiny hairs. The hairs detect chemicals in food and then your brain tells you the flavour. We have five basic tastes, and these are sweet, sour, salty, bitter and umani (a savoury taste.) Children have around 10,000 taste buds, but these numbers decline with age.
- Sight – The eye is like a camera. Light from an image passes through the cornea and it is adjusted, causing an upside down image on the retina at the back of the eye. This information is then translated by the brain and turned the correct way up.