Activity 7.1 NCERT class 10 Science Control and Coordination
Activity 7.1 asks us to check if the nose has any effect on the taste of food. For this it asks us to eat sugar once with nose open, and once with nose closed; in another instance, it asks us to repeat the same with some other food.
Sugar tastes same whether nose closed or open.
Food tastes different when we close the nose while eating.
When we bring food to our mouth, sensory organs inside the tongue and nose receives the sensory signal. Our brain interprets the signal and tells us about the food. By this, we can know the type of food, and we can even guess the name. When we eat sugar sweet sensor present in the tongue tell us it is sugar. Since there is no smell in sugar, we do not feel any difference in the taste even if our nose is closed. But when we taste different food ingredient, there is smell part also. The food contains various volatile components like volatile oil in fennel, clove, volatile ester in fruits. When our nose is closed, our brain receives the signal only from taste buds. As a result, the taste feels different. The impact is such that many people can not guess the food if their eyes and nose are closed while eating.
This experiment demonstrates that taste and smell both help the brain in interpreting the food.