3.8 billion – 2.5 billion years ago
The Archean is the name of the age which started with the shaping Earth. This time of Earth's history endured quite a while, over 2.5 billion years. When the archean age ended the earth was just coming alive.
There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration. The airway, which includes the nose, mouth, pharynx, larynx, trachea, bronchi, and bronchioles, carries air between the lungs and the body's exterior.
Hippocrates is credited with being the first person to believe that diseases were caused naturally, not because of superstition and gods. Hippocrates was credited by the disciples of Pythagoras of allying philosophy and medicine. It was in anatomy that Herophilus made his greatest contribution to medical science, conducting important anatomical investigations of the brain, eye, nervous and vascular systems, and the genital organs. He also wrote on obstetrics and gynecology and held an elaborate quantitative theory of the pulse
