Why do fruits become soft when ripe?

The cells of the raw fruit or vegetable are tightly packed and are held rigidly together by a carbohydrate called pectin which forms a strong bond with the walls of the coils and cements the cells together. As the fruit ripens, enzymes in the cells dissolve the pectin. When this happens the cells are no longer lightly bound to each other and the fruit becomes soft to the touch. Healing also dissolves the pectin. This is why vegetables and fruit become soft when cooked.

Taking the Temperature -thermometer

When you have a fever, the temperature is taken with the help of a thermometer. The bulb of the thermometer is normally placed under the tongue or in the armpit or groin. What's the reason? For a correct reading of body temperature, the bulb of the thermometer (which contains mercury) has to be in direct contact with the body's surface. If the thermometer is placed simply inside the mouth, it may not give a correct reading, as the bulb may not be in contact with the tongue. In such a case the temperature recorded will be that of the air and saliva in the mouth.