TELL ME WHY 2

Why Are Microscopes Used?

The word microscope is a combustion of two Greek words , mikros or 'small' and skopos or 'watcher'. So this means that a microscope is a 'watcher of small' objects. It is an instrument that is used to see tiny things which are invisible to the naked eye.

Normally an object appears larger the closer it is brought to the human eye. But when it is nearer than 10 inches (25.5 cm) it becomes blurred. It is said to be out of focus. Now if a simple convex lens is placed between the eye and the object, the object can be brought nearer than 10 inches and still remain focus. Today the microscope is important to man in almost every form of industry.

It was a Dutchman called Antonie van Leeuwenhoek (1632-1723) who discovered ground glass lenses which he used to examine the world about him. In the 1670's he made his first crude microscope with a tiny lens. This allowed him to be the first person to see microscopic life such as bacteria.

TELL ME WHY

Why Do We Have Skin?

Skin is a flexible, waterproof covering that protects us from the outside world. It prevents harmful germs from entering the body. Skin is your largest organ and it is sensitive to touch, temperature and pain. Your skin tells you what is happening around your body, so you can avoid injuring yourself. It also helps to prevent damage from the Sun's harmful ultraviolet rays. Finally skin helps to regulate body temperature by sweating and flushing to lose heat when you get too hot.

Science Student