The passion for gladiator combat had grown to a national scale in 106 B.C.E, and the system of fights caught the interest of magistrates- elected officials who held positions of authority in ancient Rome. A gladiator training school was called a Ludus and its head a Lanista. It was mandatory that a doctor lived in every Ludus , as the health of each gladiator was valued and protected.

Usually plants get all the elements they need for growth and development from soil and air, but some of them have adapted to the predatory way of life. They absorb nutrients in the usual way but also digest small insects. The first predator plants emerged about 55 million years ago, and all existing groups are known to have existed from Miocene, which began about 25 million years ago, which is quite a while according to evolutionary standards.

Matter, substance and Molecules are the major concept that helps ease the study of the surrounding world. There is an estabilished opinion that most scientific ideas came to us from ancient Greece. Natural sciences are no exception. Aristotle started with a simple concept of matter being made up of four elements-fires, water, air and earth. He also pointed out their qualities to be hot, cold, dry and wet. His compatriot, Thales simplified everything to be water in certain density. Leucippus and his most famous student Democritus were more progressive thinkers. Democritus suggested that the ultimate divisibility of matter with the smallest particle being the” Atom”.

The salt which we add to our food is composed mainly of sodium chloride,’ NaCl ’. In nature, this compound is found in the form of mineral halite, the basic of the so called rock salt. It is one of the most widespread compounds on Earth.