How do they make the holes in Swiss cheese?
Swiss cheese is made in wheels of about 90 centimetres in diameter and 15 cm thick. The round holes inside the cheese are known as eyes in the industry. The eyes are about 1.6 cm wide and roughly 5 cm to 8 cm apart. They are produced by a build-up of pockets of gas from bacterial action.
Pure strains of certain bacterium are used to control the development of acid, eyes, and flavour. Bacteria inside the cheese produce large amounts of carbon dioxide gas. Pockets of the gas build up to form the round holes after six to eight weeks.
Why do cicadas make so much noise?
Cicadas are flying plant-feeding insects between three and five centimetres long, with a pair of membranous wings and big bulging eyes.
In most species of cicadas, it is only the males that make a loud, sometimes even deafening, buzzing noise that can be heard over a long distance. Only the males have ridged membranes called timbals on their abdomens which they vibrate to produce the buzzing. The abdomen has a hollow space that acts as a resonating chamber to amplify the sound.