SCF3C1_tongue_skin PDF

The Tongue and the Sense of Taste 1. The tongue is a sensory organ that gives us the sense of taste. 2. The surface of the tongue is covered with taste buds. 3. Each taste bud contains many taste receptors. 4. Taste receptors are sensitive to the chemicals in food. 5. The tongue has 5 types of tast...

The Tongue and the Sense of Taste 1. The tongue is a sensory organ that gives us the sense of taste. 2. The surface of the tongue is covered with taste buds. 3. Each taste bud contains many taste receptors. 4. Taste receptors are sensitive to the chemicals in food. 5. The tongue has 5 types of taste receptors: Sweet Sour Salty Bitter Umami (savoury taste) 6. These taste receptors are distributed all over the tongue. 7. This means that the ability to taste is not restricted to a single part of the tongue. 8. The higher the number of taste buds that you have, the more number of taste receptors on your tongue. 9. This means that people with higher number of taste buds are more sensitive to taste and can taste food better. 10. How do we taste food? The flowchart below will show you the mechanism of tasting: Skin and the Sense of Touch 1. The skin is a sensory organ that detects touch. 2. There are thousands of receptors on the skin. 3. These receptors are sensitive to certain stimuli such as: Pain Touch Temperature Pressure 4. The diagram below will show you the cross-section of the human skin and their various receptors. 5. The skin on different parts of the body has different degrees of sensitivity. 6. The parts of the skin that are very sensitive to the touch stimuli are the fingertips, the back of the neck, lips and ear pinna. 7. Parts of skin that are less sensitive to the touch stimuli are the elbow and knee. 8. The sensitivity of the skin depends on: a) The number of receptors present The higher the number of receptors present, the more sensitive the skin. The nearer the receptors are to each other, the more sensitive the skin is to stimuli b) The thickness of the epidermis The thinner the epidermis, the more sensitive the part of the skin 9. Blind people can read Braille by feeling the surface of the paper, due to the high sensitivity of their fingertips. 10. Injections are usually given on the forearms and buttocks because the skin in these areas are less sensitive to touch and pain compared to the skin on other parts of the body.